Results from the UNITED study: a multicenter study validating the prognostic effect of the tumor-stroma ratio in colon cancer

BACKGROUND

The TNM (tumor-node-metastasis) Evaluation Committee of Union for International Cancer Control (UICC) and College of American Pathologists (CAP) recommended to prospectively validate the cost-effective and robust tumor-stroma ratio (TSR) as an independent prognostic parameter, since high intratumor stromal percentages have previously predicted poor patient-related outcomes.

PATIENTS AND METHODS

The 'Uniform Noting for International application of Tumor-stroma ratio as Easy Diagnostic tool' (UNITED) study enrolled patients in 27 participating centers in 12 countries worldwide. The TSR, categorized as stroma-high (>50%) or stroma-low (≤50%), was scored through standardized microscopic assessment by certified pathologists, and effect on disease-free survival (DFS) was evaluated with 3-year median follow-up. Secondary endpoints were benefit assessment of adjuvant chemotherapy (ACT) and overall survival (OS).

RESULTS

A total of 1537 patients were included, with 1388 eligible stage II/III patients curatively operated between 2015 and 2021. DFS was significantly shorter in stroma-high (n = 428) than in stroma-low patients (n = 960) (3-year rates 70% versus 83%; P < 0.001). In multivariate analysis, TSR remained an independent prognosticator for DFS (P < 0.001, hazard ratio 1.49, 95% confidence interval 1.17-1.90). As secondary outcome, DFS was also worse in stage II and III stroma-high patients despite adjuvant treatment (3-year rates stage II 73% versus 92% and stage III 66% versus 80%; P = 0.008 and P = 0.011, respectively). In stage II patients not receiving ACT (n = 322), the TSR outperformed the American Society of Clinical Oncology (ASCO) criteria in identifying patients at risk of events (event rate 21% versus 9%), with a higher discriminatory 3-year DFS rate (stroma-high 80% versus ASCO high risk 91%). A trend toward worse 5-year OS in stroma-high was noticeable (74% versus 83% stroma-low; P = 0.102).

CONCLUSION

The multicenter UNITED study unequivocally validates the TSR as an independent prognosticator, confirming worse outcomes in stroma-high patients. The TSR improved current selection criteria for patients at risk of events, and stroma-high patients potentially experienced chemotherapy resistance. TSR implementation in pathology diagnostics and international guidelines is highly recommended as aid in personalized treatment.

Laparoscopic peritoneal lavage versus sigmoidectomy for perforated diverticulitis with purulent peritonitis: three-year follow-up of the randomised LOLA trial

Background

This study aimed to compare laparoscopic lavage and sigmoidectomy as treatment for perforated diverticulitis with purulent peritonitis during a 36 month follow-up of the LOLA trial.

Methods

Within the LOLA arm of the international, multicentre LADIES trial, patients with perforated diverticulitis with purulent peritonitis were randomised between laparoscopic lavage and sigmoidectomy. Outcomes were collected up to 36 months. The primary outcome of the present study was cumulative morbidity and mortality. Secondary outcomes included reoperations (including stoma reversals), stoma rates, and sigmoidectomy rates in the lavage group.

Results

Long-term follow-up was recorded in 77 of the 88 originally included patients, 39 were randomised to sigmoidectomy (51%) and 38 to laparoscopic lavage (49%). After 36 months, overall cumulative morbidity (sigmoidectomy 28/39 (72%) versus lavage 32/38 (84%), p = 0·272) and mortality (sigmoidectomy 7/39 (18%) versus lavage 6/38 (16%), p = 1·000) did not differ. The number of patients who underwent a reoperation was significantly lower for lavage compared to sigmoidectomy (sigmoidectomy 27/39 (69%) versus lavage 17/38 (45%), p = 0·039). After 36 months, patients alive with stoma in situ was lower in the lavage group (proportion calculated from the Kaplan–Meier life table, sigmoidectomy 17% vs lavage 11%, log-rank p = 0·0268). Eventually, 17 of 38 (45%) patients allocated to lavage underwent sigmoidectomy.

Conclusion

Long-term outcomes showed that laparoscopic lavage was associated with less patients who underwent reoperations and lower stoma rates in patients alive after 36 months compared to sigmoidectomy. No differences were found in terms of cumulative morbidity or mortality. Patient selection should be improved to reduce risk for short-term complications after which lavage could still be a valuable treatment option.

Graphical abstract

Longitudinal changes of serum protein N-Glycan levels for earlier detection of pancreatic cancer in high-risk individuals

BACKGROUND

Surveillance of individuals at risk of developing pancreatic ductal adenocarcinoma (PDAC) has the potential to improve survival, yet early detection based on solely imaging modalities is challenging. We aimed to identify changes in serum glycosylation levels over time to earlier detect PDAC in high-risk individuals.

METHODS

Individuals with a hereditary predisposition to develop PDAC were followed in two surveillance programs. Those, of which at least two consecutive serum samples were available, were included. Mass spectrometry analysis was performed to determine the total N-glycome for each consecutive sample. Potentially discriminating N-glycans were selected based on our previous cross-sectional analysis and relative abundances were calculated for each glycosylation feature.

RESULTS

165 individuals ("FPC-cohort" N = 119; Leiden cohort N = 46) were included. In total, 97 (59%) individuals had a genetic predisposition (77 CDKN2A, 15 BRCA1/2, 5 STK11) and 68 (41%) a family history of PDAC without a known genetic predisposition (>10-fold increased risk of developing PDAC). From each individual, a median number of 3 serum samples (IQR 3) was collected. Ten individuals (6%) developed PDAC during 35 months of follow-up; nine (90%) of these patients carried a CDKN2A germline mutation. In PDAC cases, compared to all controls, glycosylation characteristics were increased (fucosylation, tri- and tetra-antennary structures, specific sialic linkage types), others decreased (complex-type diantennary and bisected glycans). The largest change over time was observed for tri-antennary fucosylated glycans, which were able to differentiate cases from controls with a specificity of 92%, sensitivity of 49% and accuracy of 90%.

CONCLUSION

Serum N-glycan monitoring may support early detection in a pancreas surveillance program.

National differences in implementation of minimally invasive surgery for colorectal cancer and the influence on short-term outcomes

Background

The timing and degree of implementation of minimally invasive surgery (MIS) for colorectal cancer vary among countries. Insights in national differences regarding implementation of new surgical techniques and the effect on postoperative outcomes are important for quality assurance, can show potential areas for country-specific improvement, and might be illustrative and supportive for similar implementation programs in other countries. Therefore, this study aimed to evaluate differences in patient selection, applied techniques, and results of minimal invasive surgery for colorectal cancer between the Netherlands and Sweden.

Methods

Patients who underwent elective minimally invasive surgery for T1-3 colon or rectal cancer (2012–2018) registered in the Dutch ColoRectal Audit or Swedish ColoRectal Cancer Registry were included. Time trends in the application of MIS were determined. Outcomes were compared for time periods with a similar level of MIS implementation (Netherlands 2012–2013 versus Sweden 2017–2018). Multilevel analyses were performed to identify factors associated with adverse short-term outcomes.

Results

A total of 46,095 Dutch and 8,819 Swedish patients undergoing MIS for colorectal cancer were included. In Sweden, MIS implementation was approximately 5 years later than in the Netherlands, with more robotic surgery and lower volumes per hospital. Although conversion rates were higher in Sweden, oncological and surgical outcomes were comparable. MIS in the Netherlands for the years 2012–2013 resulted in a higher reoperation rate for colon cancer and a higher readmission rate but lower non-surgical complication rates for rectal cancer if compared with MIS in Sweden during 2017–2018.

Conclusion

This study showed that the implementation of MIS for colorectal cancer occurred later in Sweden than the Netherlands, with comparable outcomes despite lower volumes. Our study demonstrates that new surgical techniques can be implemented at a national level in a controlled and safe way, with thorough quality assurance.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00464-021-08974-1.

Postoperative complications after colorectal cancer surgery and the association with long-term survival

BACKGROUND

Complications after colorectal cancer surgery can worsen long-term survival. The aim of this nationwide study was to determine the impact of different types of complications on overall survival (OS) and conditional survival if still alive one year postoperatively (CS-1) after colorectal cancer surgery.

MATERIALS AND METHODS

All patients registered in the Dutch ColoRectal Audit after resection of primary colorectal cancer between 2011 and 2017 and with known survival status were included. Multivariable Cox regression models were used to assess the association of complications with OS and CS-1, thereby calculating the Hazard Ratio (HR) with 95% Confidence Interval.

RESULTS

43,908 colon and 16,955 rectal cancer patients were included. Median follow-up time was 66.1 and 66.5 months, respectively. Five-year OS after colon cancer resection was 73.2% without complications, and 65.4% with surgical, 52.9% with non-surgical and 51.8% with combined type of complications (p < 0.001). Corresponding 5-year OS for rectal cancer patients was 76.9%, 72.7%, 64.9%, and 63.2% (p < 0.001). In colon cancer, multivariable analyses revealed HR 1.198 (1.136-1.264) for surgical, HR 1.489 (1.423-1.558) for non-surgical and HR 1.590 (1.505-1.681) for combined type of complications. For rectal cancer, these HRs were 1.193 (1.097-1.2297), 1.456 (1.346-1.329), and 1.489 (1.357-1.633). Surgical complications were associated with worse CS-1 in rectal cancer (HR 1.140 (1.050-1.260), but not in colon cancer (HR 1.007 (0.943-1.075)).

CONCLUSION

Non-surgical complications have higher impact on survival than surgical complications. The impact of surgical complications on survival was still measurable after surviving the first year in rectal cancer but not in colon cancer patients.

Textbook outcome after rectal cancer surgery as a composite measure for quality of care: A population-based study

BACKGROUND

Textbook outcome is a composite measure of combined outcome indicators, which has been suggested to be of additional value over single outcome parameters in clinical auditing of surgical treatment. This study aimed to assess textbook outcome after rectal cancer surgery as short-term marker for quality of care.

MATERIALS AND METHODS

Patients who underwent elective rectal cancer surgery between 2012 and 2019 and registered in the Dutch ColoRectal Audit were included. Textbook outcome was achieved when the following criteria were met: 30-day and primary hospital admission survival, no reintervention, tumour-free margins, no postoperative complications, a hospital stay of less than 14 days and no readmission. Hospital variation was evaluated in case-mix corrected funnel-plots. A multilevel logistic regression analysis was performed to identify associated factors with textbook outcome.

RESULTS

The study population consisted of 20,521 patients who underwent primary rectal cancer surgery, of whom 56.3% achieved textbook outcome. Postoperative complications were the main contributor to not achieving textbook outcome. Case-mix corrected funnel plots demonstrated that underperforming hospitals in 2012-2015 were no underperformers in 2016-2019 anymore. Female sex, laparoscopic surgery, and rectal resection without defunctioning stoma creation were positively associated with textbook outcome.

CONCLUSION

Textbook outcome after rectal cancer resection is mainly driven by postoperative complications. Although textbook outcome showed some discriminating value for identifying underperforming hospitals, it does not fit the plan-do-check-act cycle of clinical auditing. In our opinion, textbook outcome has little added value to the current outcome indicators for rectal cancer surgery.

Rates of re-excision and conversion to mastectomy after breast-conserving surgery with or without oncoplastic surgery: a nationwide population-based study

Background

There is no consensus regarding the impact of oncoplastic surgery (OPS) on rates of re‐excision and conversion to mastectomy following breast‐conserving surgery (BCS). Here these two outcomes after BCS and OPS were compared in a nationwide population‐based setting.

Methods

In Denmark, all OPS is registered and categorized into volume displacement, volume reduction or volume replacement. Patients who underwent BCS or OPS between 2012 and 2018 were selected from the Danish Breast Cancer Group database. Multivariable analyses were performed to adjust for confounders, and propensity score matching to limit potential confounding by indication bias.

Results

A total of 13 185 patients (72·5 per cent) underwent BCS and 5003 (27·5 per cent) OPS. Volume displacement was used in 4171 patients (83·4 per cent), volume reduction in 679 (13·6 per cent) and volume replacement in 153 (3·1 per cent). Re‐excision rates were 15·6 and 14·1 per cent after BCS and OPS respectively. After adjusting for confounders, patients were less likely to have a re‐excision following OPS than BCS (odds ratio (OR) 0·80, 95 per cent c.i. 0·72 to 0·88), specifically after volume displacement and reduction. The rate of conversion to mastectomy was similar after OPS and BCS (3·2 versus 3·7 per cent; P = 0·105), but with a lower risk in adjusted analysis (OR 0·69, 0·58 to 0·84), specifically after volume displacement and reduction procedures. Findings were similar after propensity score matching.

Conclusion

A modest decrease in re‐excision rate and less frequent conversion to mastectomy were observed after OPS compared with BCS.

Breast-contour preserving procedures for early-stage breast cancer: a population-based study of the trends, variation in practice and predictive characteristics in Denmark and the Netherlands

PURPOSE

Breast-contour preservation (BCP) is possible for most women treated for early-stage breast cancer. BCP can be defined as primary breast-conserving treatment (BCT), neoadjuvant chemotherapy (NAC) followed by BCT and immediate postmastectomy breast reconstruction (IBR). This study provides insight in current BCP strategies in Denmark and the Netherlands and aims to identify opportunities for improvement within both countries.

METHODS

A total of 92,881 patients with early-stage breast cancer who were operated in Denmark and the Netherlands between 2012 and 2017 were selected from the Danish Breast Cancer Group and the Dutch National Breast Cancer Audit databases. BCP procedures and predictive factors were analyzed within and between both countries.

RESULTS

BCP was achieved in 76.7% (n = 16,355) of the Danish and in 74.5% (n = 53,328) of the Dutch patients. While BCP rate did not change significantly over time in Denmark (p = 0.250), a significant increase in BCP rate from 69.5% in 2012 to 78.5% in 2017 (p < 0.001) was observed in the Netherlands. In both countries, variation in BCP rates between hospitals decreased over time. NAC followed by BCT and postmastectomy IBR was substantially more often used in the Netherlands compared to Denmark, specifically in patients younger than 50 years.

CONCLUSIONS

In more than 75% of all Danish and Dutch patients, surgically treated for early-stage breast cancer, the breast-contour was preserved. The different use of BCP strategies within Denmark and the Netherlands and the differences observed between hospitals in both countries emphasize the need for more (inter)national consensus on treatment modalities.

Outcomes following pancreatic surgery using three different thromboprophylaxis regimens

BACKGROUND

Postpancreatectomy haemorrhage (PPH) and venous thromboembolism (VTE) are serious complications following pancreatic surgery. The aim was to assess the timing, occurrence and predictors of PPH and VTE.

METHODS

Elective pancreatic resections undertaken in a single university hospital between November 2013 and September 2017 were assessed. Three intervals were reviewed, each with a different routine regimen of nadroparin: 2850 units once daily (single dose) administered in hospital only, or 5700 units once daily (double dose) or 2850 units twice daily (split dose) administered in hospital and continued for 6 weeks after surgery. Clinically relevant PPH (CR-PPH) was classified according to International Study Group of Pancreatic Surgery criteria. VTE was defined according to a number of key diagnostic criteria within 6 weeks of surgery. Cox regression analyses were performed to test the hypotheses that the double-dose group would experience more PPH than the other two groups, the single-dose group would experience more VTE than the other two groups, and the split-dose group would experience the fewest adverse events (PPH or VTE).

RESULTS

In total, 240 patients were included, 80 per group. The double-dose group experienced significantly more CR-PPH (hazard ratio (HR) 2·14, 95 per cent c.i. 1·16 to 3·94; P = 0·015). More relaparotomies due to CR-PPH were performed in the double-dose group (16 versus 3·8 per cent; P = 0·002). The single-dose group did not experience more VTE (HR 1·41, 0·43 to 4·62; P = 0·570). The split dose was not associated with fewer adverse events (HR 0·77, 0·41 to 1·46; P = 0·422). Double-dose low molecular weight heparin (LMWH), high BMI and pancreatic fistula were independent predictors of CR-PPH.

CONCLUSION

A double dose of LMWH prophylaxis continued for 6 weeks after pancreatic resection was associated with a twofold higher rate of CR-PPH, resulting in four times more relaparotomies. Patients receiving a single daily dose of LMWH in hospital only did not experience a higher rate of VTE.

International benchmarking in oesophageal and gastric cancer surgery

Background

Benchmarking on an international level might lead to improved outcomes at a national level. The aim of this study was to compare treatment and surgical outcome data from the Swedish National Register for Oesophageal and Gastric Cancer (NREV) and the Dutch Upper Gastrointestinal Cancer Audit (DUCA).

Methods

All patients with primary oesophageal or gastric cancer who underwent a resection and were registered in NREV or DUCA between 2012 and 2014 were included. Differences in 30‐day mortality were analysed using case mix‐adjusted multivariable logistic regression.

Results

In total, 4439 patients underwent oesophagectomy (2509 patients) or gastrectomy (1930 patients). Estimated resection rates were comparable. Swedish patients were older but had less advanced disease and less co‐morbidity than Dutch patients. Neoadjuvant treatment rates were lower in Sweden than in the Netherlands, both for patients who underwent oesophagectomy (68·6 versus 90·0 per cent respectively; P < 0·001) and for those having gastrectomy (38·3 versus 56·6 per cent; P < 0·001). In Sweden, transthoracic oesophagectomy was performed in 94·7 per cent of patients, whereas in the Netherlands, a transhiatal approach was undertaken in 35·8 per cent. Higher annual procedural volumes per hospital were observed in the Netherlands. Adjusted 30‐day and/or in‐hospital mortality after gastrectomy was statistically significantly lower in Sweden than in the Netherlands (odds ratio 0·53, 95 per cent c.i. 0·29 to 0·95).

Conclusion

For oesophageal and gastric cancer, there are differences in patient, tumour and treatment characteristics between Sweden and the Netherlands. Postoperative mortality in patients with gastric cancer was lower in Sweden.

Prognostic value of tumor-stroma ratio combined with the immune status of tumors in invasive breast carcinoma

PURPOSE

Complex interactions occur between cancer cells and cells in the tumor microenvironment. In this study, the prognostic value of the interplay between tumor-stroma ratio (TSR) and the immune status of tumors in breast cancer patients was evaluated.

METHODS

A cohort of 574 breast cancer patients was analyzed. The percentage of tumor stroma was visually estimated on Hematoxylin and Eosin (H&E) stained histological tumor tissue sections. Immunohistochemical staining was performed for classical human leukocyte antigen (HLA) class I, HLA-E, HLA-G, markers for regulatory T (Treg) cells, natural killer (NK) cells and cytotoxic T-lymphocytes (CTLs).

RESULTS

TSR (P < .001) and immune status of tumors (P < .001) were both statistically significant for recurrence free period (RFP) and both independent prognosticators (P < .001) in which tumors with a high stromal content behave more aggressively as well as tumors with a low immune status. Ten years RFP for patients with a stroma-low tumor and high immune status profile was 87% compared to 17% of patients with a stroma-high tumor combined with low immune status profile (P < .001). Classical HLA class I is the most prominent immune marker in the immune status profiles.

CONCLUSIONS

Determination of TSR is a simple, fast and cheap method. The effect on RFP of TSR when combined with immune status of tumors or expression of classical HLA class I is even stronger. Both are promising for further prediction and achievement of tailored treatment for breast cancer patients.

Timing of risk reducing mastectomy in breast cancer patients carrying a BRCA1/2 mutation: retrospective data from the Dutch HEBON study

It is expected that rapid genetic counseling and testing (RGCT) will lead to increasing numbers of breast cancer (BC) patients knowing their BRCA1/2 carrier status before primary surgery. Considering the potential impact of knowing one’s status on uptake and timing of risk-reducing contralateral mastectomy (RRCM), we aimed to evaluate trends over time in RRCM, and differences between carriers identified either before (predictively) or after (diagnostically) diagnosis. We collected data from female BRCA1/2 mutation carriers diagnosed with BC between 1995 and 2009 from four Dutch university hospitals. We compared the timing of genetic testing and RRCM in relation to diagnosis in 1995–2000 versus 2001–2009 for all patients, and predictively and diagnostically tested patients separately. Of 287 patients, 219 (76 %) had a diagnostic BRCA1/2 test. In this cohort, the median time from diagnosis to DNA testing decreased from 28 months for those diagnosed between 1995 and 2000 to 14 months for those diagnosed between 2001 and 2009 (p < 0.001). Similarly, over time women in this cohort underwent RRCM sooner after diagnosis (median of 77 vs. 27 months, p = 0.05). Predictively tested women who subsequently developed BC underwent an immediate RRCM significantly more often than women who had a diagnostic test (21/61, 34 %, vs. 13/170, 7.6 %, p < 0.001). Knowledge of carrying a BRCA1/2 mutation when diagnosed with BC influenced decisions concerning primary surgery. Additionally, in more recent years, women who had not undergone predictive testing were more likely to undergo diagnostic DNA testing and RRCM sooner after diagnosis. This suggests the need for RGCT to guide treatment decisions.

Fine-mapping identifies two additional breast cancer susceptibility loci at 9q31.2

We recently identified a novel susceptibility variant, rs865686, for estrogen-receptor positive breast cancer at 9q31.2. Here, we report a fine-mapping analysis of the 9q31.2 susceptibility locus using 43 160 cases and 42 600 controls of European ancestry ascertained from 52 studies and a further 5795 cases and 6624 controls of Asian ancestry from nine studies. Single nucleotide polymorphism (SNP) rs676256 was most strongly associated with risk in Europeans (odds ratios [OR] = 0.90 [0.88-0.92]; P-value = 1.58 × 10(-25)). This SNP is one of a cluster of highly correlated variants, including rs865686, that spans ∼14.5 kb. We identified two additional independent association signals demarcated by SNPs rs10816625 (OR = 1.12 [1.08-1.17]; P-value = 7.89 × 10(-09)) and rs13294895 (OR = 1.09 [1.06-1.12]; P-value = 2.97 × 10(-11)). SNP rs10816625, but not rs13294895, was also associated with risk of breast cancer in Asian individuals (OR = 1.12 [1.06-1.18]; P-value = 2.77 × 10(-05)). Functional genomic annotation using data derived from breast cancer cell-line models indicates that these SNPs localise to putative enhancer elements that bind known drivers of hormone-dependent breast cancer, including ER-α, FOXA1 and GATA-3. In vitro analyses indicate that rs10816625 and rs13294895 have allele-specific effects on enhancer activity and suggest chromatin interactions with the KLF4 gene locus. These results demonstrate the power of dense genotyping in large studies to identify independent susceptibility variants. Analysis of associations using subjects with different ancestry, combined with bioinformatic and genomic characterisation, can provide strong evidence for the likely causative alleles and their functional basis.

Comparing colon cancer outcomes: The impact of low hospital case volume and case-mix adjustment

OBJECTIVE

When comparing performance across hospitals it is essential to consider the noise caused by low hospital case volume and to perform adequate case-mix adjustment. We aimed to quantify the role of noise and case-mix adjustment on standardized postoperative mortality and anastomotic leakage (AL) rates.

METHODS

We studied 13,120 patients who underwent colon cancer resection in 85 Dutch hospitals. We addressed differences between hospitals in postoperative mortality and AL, using fixed (ignoring noise) and random effects (incorporating noise) logistic regression models with general and additional, disease specific, case-mix adjustment.

RESULTS

Adding disease specific variables improved the performance of the case-mix adjustment models for postoperative mortality (c-statistic increased from 0.77 to 0.81). The overall variation in standardized mortality ratios was similar, but some individual hospitals changed considerably. For the standardized AL rates the performance of the adjustment models was poor (c-statistic 0.59 and 0.60) and overall variation was small. Most of the observed variation between hospitals was actually noise.

CONCLUSION

Noise had a larger effect on hospital performance than extended case-mix adjustment, although some individual hospital outcome rates were affected by more detailed case-mix adjustment. To compare outcomes between hospitals it is crucial to consider noise due to low hospital case volume with a random effects model.

Disorganised stroma determined on pre-treatment breast cancer biopsies is associated with poor response to neoadjuvant chemotherapy: Results from the NEOZOTAC trial

INTRODUCTION

The tumor-associated stroma is of importance for tumor progression and is generally accepted to have a significant influence on patient prognosis. However, little is known regarding specific features of tumor-associated stromal tissues and response to (neoadjuvant) chemotherapy. This study investigated the predictive value of extracellular matrix organization on response to chemotherapy in patients treated in the NEOZOTAC trial.

METHODS

Stromal organisation was analyzed via a simple method using image analysis software on hematoxylin and eosin (H&E)-stained slides from primary tumor biopsies collected as part of the NEOZOTAC trial. Heidenhain's AZAN trichrome-stained slides were also analyzed for comparison of collagen evaluation. Sections were stained for phospho-Smad2 (pS2) in order to determine the relationship of TGF-β signaling with stromal organization.

RESULTS

A statistically significant relationship was observed between stroma consisting of organised collagen and pathological response to neoadjuvant chemotherapy (Odds Ratio 0.276, 95%CI 0.124-0.614, P = 0.002). This parameter was also related to ER-status (P = 0.003), clinical tumor -status (P = 0.041), nodal status (P = 0.029) and pS2 status (P = 0.025). Correlation between stromal organisation determined on H&E-stained and AZAN-stained tissue sections was high (Pearson's correlation coefficient = 0.806).

CONCLUSION

Intratumoral stromal organisation determined using pre-treatment breast cancer biopsies was related to pathological response to chemotherapy. This parameter might play a role in the management of breast cancer for identifying those patients that are likely to benefit from neoadjuvant chemotherapy.

Complicated postoperative recovery increases omission, delay and discontinuation of adjuvant chemotherapy in patients with Stage III colon cancer

AIM

The study included investigation of factors determining suboptimal adjuvant chemotherapy of patients diagnosed with Stage III colon cancer.

METHOD

All 606 patients diagnosed with Stage III colon cancer between 2006 and 2008 in the western part of the Netherlands were included. Patient [gender, age, comorbidity and socio-economic status (SES)], tumour (location, stage and grade) and treatment (emergency surgery, laparoscopic surgery, reoperation, hospital stay and multidisciplinary meeting) factors were examined in logistic regression analyses predicting a complicated postoperative period and omission, delay and discontinuation of adjuvant chemotherapy.

RESULTS

Overall, 27% of all patients experienced a complicated postoperative period, which was independently associated with emergency surgery, older age, multiple comorbidity, male gender and poor tumour grade. Of patients who survived this period, 60% received chemotherapy. Chemotherapy was omitted more often in women, the elderly and in patients with Stage IIIB, reoperation, prolonged hospital stay and (borderline) after open surgery. Of patients who received chemotherapy, 86% started within 8 weeks after surgery. Patients with a higher SES, reoperation and prolonged hospital stay had a higher probability of a delayed start. Sixty-seven per cent of patients completed their chemotherapy. For women, elderly patients and patients with prolonged hospital stay a higher probability of discontinuation was noted.

CONCLUSION

Age was the most important predictive factor for receiving adjuvant chemotherapy. However, at all ages, complicated postoperative recovery negatively influenced the administration of chemotherapy to Stage III colon cancer patients, as well as a timely start and completion of chemotherapy.

Case-controlled identification of colorectal cancer based on proteomic profiles and the potential for screening

AIM

Colorectal cancer (CRC) screening programmes detect early cancers but unfortunately have limited sensitivity and specificity. Mass spectrometry-based determination of serum peptide and protein profiles provides a new approach for improved screening.

METHOD

Serum samples were obtained from 126 CRC patients before treatment and 277 control individuals. An additional group of samples from 50 CRC patients and 82 controls was used for validation. Peptide and protein enrichments were carried out using reverse-phase C18 and weak-cation exchange magnetic beads in an automated solid-phase extraction and spotting procedure. Profiles were acquired on a matrix-assisted laser desorption/ionization time-of-flight system. Discriminant rules using logistic regression were calibrated for the peptide and protein signatures separately, followed by combining the classifications to obtain double cross-validated predicted class probabilities. Results were validated on an identical patient set.

RESULTS

A discriminative power was found for patients with CRC representative for all histopathological stages compared with controls with an area under the curve of 0.95 in the test set (0.93 for the validation set) and with a high specificity (94-95%).

CONCLUSION

The study has shown that a serum peptide and protein biomarker signature can be used to distinguish CRC patients from healthy controls with high discriminative power. This relatively simple and cheap test is promising for CRC screening.

Isolated hepatic perfusion with oxaliplatin combined with 100 mg melphalan in patients with metastases confined to the liver: A phase I study

AIM

To improve isolated hepatic perfusion (IHP), we performed a phase I dose-escalation study to determine the optimal oxaliplatin dose in combination with a fixed melphalan dose.

METHODS

Between June 2007 and July 2008, 11 patients, comprising of 8 colorectal cancer and 3 uveal melanoma patients and all with isolated liver metastases, were treated with a one hour IHP with escalating doses of oxaliplatin combined with 100 mg melphalan. Samples of blood and perfusate were taken during IHP treatment for pharmacokinetic analysis of both drugs and patients were monitored for toxicity, response and survival.

RESULTS

Dose limiting sinusoidal obstruction syndrome (SOS) occurred at 150 mg oxaliplatin. The areas under the concentration-time curves (AUC) of oxaliplatin at the maximal tolerated dose (MTD) of 100 mg oxaliplatin ranged from 11.9 mg/L h to 16.5 mg/L h. All 4 patients treated at the MTD showed progressive disease 3 months after IHP.

CONCLUSIONS

In view of similar and even higher doses of oxaliplatin applied in both systemic treatment and hepatic artery infusion (HAI), applying this dose in IHP is not expected to improve treatment results in patients with isolated hepatic metastases.

Cause of death the first year after curative colorectal cancer surgery; a prolonged impact of the surgery in elderly colorectal cancer patients

BACKGROUND

The 1-year mortality after colorectal cancer surgery is high and explains age related differences in colorectal cancer survival. To gain better insight in its etiology, cause of death for these patients was studied.

METHODS

All 1924 patients who had a resection for stage I-III colorectal cancer from 2006 to 2008 in the Western region of the Netherlands were identified. Data were merged with cause of death data from the Central Bureau of Statistics Netherlands. To calculate excess mortality as compared to the general population, national data were used.

RESULTS

Overall 13.2% of patients died within the first postoperative year. One-year mortality increased with age. It was as high as 43% in elderly patients that underwent emergency surgery. In 75% of patients, death was attributed to the colorectal cancer. In 25% of all patients, registered deaths were attributed to postoperative complications. Elderly patients with comorbidity more frequently died due to complications (p < 0.01). Death of other causes was similar to background mortality according to age group.

CONCLUSION

In the presently studied cohort of patients that died within one year of surgery, cause of death was predominantly attributed to colorectal cancer. However, because it is not to be expected that in this cohort the number of deaths from recurrences is very high, the excess 1-year mortality indicates a prolonged impact of the surgery, especially in elderly patients. Therefore, in these patients we should focus on limiting the physiological impact of the surgery and be more involved in the post-hospital period.

Impact of centralization of pancreatic cancer surgery on resection rates and survival

BACKGROUND

Centralization of pancreatic surgery has been shown to reduce postoperative mortality. It is unknown whether resection rates and survival have also improved. The aim of this study was to analyse the impact of nationwide centralization of pancreatic surgery on resection rates and long-term survival.

METHODS

All patients diagnosed in the Netherlands between 2000 and 2009 with cancer of the pancreatic head were identified in the Netherlands Cancer Registry. Changes in referral pattern, resection rates and survival after pancreatoduodenectomy were analysed. Multivariable regression analysis was used to assess the impact of hospital volume (20 or more procedures per year) on survival after resection.

RESULTS

Between 2000 and 2009, 11,160 patients were diagnosed with cancer of the pancreatic head. The resection rate increased from 10.7 per cent in 2000-2004 to 15.3 per cent in 2005-2009 (P < 0.001). No significant difference in survival after resection was observed between the two intervals (P = 0.135), although survival was significantly better in high-volume hospitals (median survival 18 months versus 16 months in low/medium-volume hospitals; P = 0.017). After adjustment for patient and tumour characteristics, high hospital volume remained associated with better overall survival after resection (hazard ratio 0.70, 95 per cent confidence interval 0.58 to 0.84; P < 0.001).

CONCLUSION

Centralization of pancreatic cancer surgery led to increased resection rates. High-volume centres had significantly better survival rates. Centralization improves patient outcomes and should be encouraged.

High 1-year complication rate after anterior resection for rectal cancer

BACKGROUND

Surgical options after anterior resection for rectal cancer include a primary anastomosis, anastomosis with a defunctioning stoma, and an end colostomy. This study describes short-term and 1-year outcomes of these different surgical strategies.

METHODS

Patients undergoing surgical resection for primary mid and high rectal cancer were retrospectively studied in seven Dutch hospitals with 1-year follow-up. Short-term endpoints were postoperative complications, re-interventions, prolonged hospital stay, and mortality. One-year endpoints were unplanned readmissions and re-interventions, presence of stoma, and mortality.

RESULTS

Nineteen percent of 388 included patients received a primary anastomosis, 55% an anastomosis with defunctioning stoma, and 27% an end colostomy. Short-term anastomotic leakage was 10% in patients with a primary anastomosis vs. 7% with a defunctioning stoma (P = 0.46). An end colostomy was associated with less severe re-interventions. One-year outcomes showed low morbidity and mortality rates in patients with an anastomosis. Patients with a defunctioning stoma had high (18%) readmissions and re-intervention (12%) rates, mostly due to anastomotic leakage. An end colostomy was associated with unplanned re-interventions due to stoma/abscess problems. During follow-up, there was a 30% increase in patients with an end colostomy.

CONCLUSIONS

This study showed a high 1-year morbidity rate after anterior resection for rectal cancer. A defunctioning stoma was associated with a high risk for late complications including anastomotic leakage. An end colostomy is a safe alternative to prevent anastomotic leakage, but stomal problems cannot be ignored. Selecting low-risk patients for an anastomosis may lead to favorable short- and 1-year outcomes.

High complication rate after low anterior resection for mid and high rectal cancer; results of a population-based study

BACKGROUND

Surgical resection is the cornerstone of treatment for rectal cancer patients. Treatment options consist of a primary anastomosis, anastomosis with defunctioning stoma or end-colostomy with closure of the distal rectal stump. This study aimed to compare postoperative outcome of these three surgical options.

METHODS

Data was derived from the national database of the Dutch Surgical Colorectal Audit. Mid and high rectal cancer patients who underwent rectal cancer resection between January 2011 and December 2012 were included. Endpoints were postoperative complications including anastomotic leakage, reinterventions, hospital stay and mortality within 30 days postoperative.

RESULTS

In total, 2585 patients were included. Twenty-five per cent of all patients received a primary anastomosis; 51% an anastomosis with defunctioning stoma, and 24% an end-colostomy. More than one third of patients developed postoperative complications, the lowest rate being in the primary anastomosis group. Anastomotic leakage rates were 12% in patients with a primary anastomosis, and 9% in patients with an anastomosis with defunctioning stoma (p < 0.05). Multivariate analysis showed more postoperative complications, prolonged hospital stay, and increased mortality rates in patients with a defunctioning stoma or end-colostomy. The latter had proportionally less invasive reinterventions when compared to the other two groups.

CONCLUSIONS

Patients with a primary anastomosis had the best postoperative outcome. A defunctioning stoma leads to a lower anastomotic leakage rate, though is associated with higher rates of complications, prolonged hospital stay and mortality. The decision to create a defunctioning stoma should be focus of future studies.

FGF receptor genes and breast cancer susceptibility: results from the Breast Cancer Association Consortium

BACKGROUND

Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying genotyped single-nucleotide polymorphisms (SNPs) and imputed SNPs in FGFR1, FGFR3, FGFR4 and FGFRL1 in the Breast Cancer Association Consortium.

METHODS

Data were combined from 49 studies, including 53 835 cases and 50 156 controls, of which 89 050 (46 450 cases and 42 600 controls) were of European ancestry, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression.

RESULTS

Little evidence of association with breast cancer risk was observed for SNPs in the FGF receptor genes. The strongest evidence in European women was for rs743682 in FGFR3; the estimated per-allele odds ratio was 1.05 (95% confidence interval=1.02-1.09, P=0.0020), which is substantially lower than that observed for SNPs in FGFR2.

CONCLUSION

Our results suggest that common variants in the other FGF receptors are not associated with risk of breast cancer to the degree observed for FGFR2.

Preoperative risk information and patient involvement in surgical treatment for rectal and sigmoid cancer

AIM

Surgery for rectal and sigmoid cancer is a model setting for investigating preoperative information provision and shared decision making (SDM), as the decision consists of a trade-off between the pros and cons of different treatment options. The aim of this study was to explore surgeons' opinion on the preoperative information that should be given to rectal and sigmoid cancer patients and to evaluate what is actually communicated. In addition, we assessed surgeons' attitudes towards SDM and compared these with patient involvement.

METHOD

A questionnaire was sent to Dutch surgeons with an interest in gastroenterology. Preoperative consultations were recorded. A checklist was used to code the information that surgeons communicated to the patients. The OPTION-scale was used to measure patient involvement.

RESULTS

Questionnaires were sent to 240 surgeons, and 103 (43%) responded. They stated that information on anastomotic leakage and its consequences, the benefits and risks of a defunctioning stoma and the impact of a stoma on quality of life were necessary preoperative information. In practice, patients were inconsistently informed of these items. Most participants agreed to using SDM in their consultations. However, in practice, most patients were offered only one treatment option and little SDM was seen. The mean OPTION-score was low (7/100).

CONCLUSION

Insufficient information is given to patients with rectal and sigmoid cancer to guide them on their preferred surgical option. Information should be given on all treatment options, together with their complications and outcome, before any decision is made.

Recent trends and future perspectives in isolated hepatic perfusion in the treatment of liver tumors

Isolated hepatic perfusion (IHP) involves a method of complete vascular isolation of the liver to enable treatment of liver tumors with high drug doses without systemic toxicity. Recent clinical studies have mainly employed IHP with melphalan with or without tumor necrosis factor-alpha and mild hyperthermia. The results of these studies demonstrate that high response and survival rates can be achieved with IHP. The current status, recent developments and future perspectives of IHP are discussed in this review.

Abstract P1-06-04: The predictive value of tumor-stroma ratio for radiological and pathological response to neoadjuvant chemotherapy in breast cancer (BC): A Dutch breast cancer trialists’ group (BOOG) side-study

Background

Intra-tumoral stroma interacts with tumor cells and has a profound effect on tumor behavior. The tumor-stroma ratio (TSR) is of prognostic value in BC and other types of solid tumors. However, the predictive value of this parameter for achieving pathological complete response (pCR) after neoadjuvant chemotherapy is unknown.

Methods

We evaluated the relation between TSR and neoadjuvant treatment response in a retrospective cohort of 69 patients (pts) treated with various regimens of neoadjuvant chemotherapy at our institution who were diagnosed with BC between 1991 and 2007 and of whom radiological response was recorded. The percentage of intra-tumoral stroma was visually estimated on diagnostic sections from primary tumor tissue by two observers. The cut-off point between stroma-rich and stroma-poor tumors was set to 50% (as determined in previous investigations). These results were validated in a cohort from the NEOZOTAC trial: a national, multicenter, randomized study comparing the efficacy of TAC (docetaxel, adriamycin and cyclophosphamide i.v. day 1) chemotherapy with or without zoledronic acid 4 mg i.v., q 3 weeks, 6 times in 250 pts with stage II/III, measurable, HER2-negative BC. Radiological response (complete or partial) was evaluated following RECIST 1.1 criteria. pCR was centrally revised and defined as absence of residual tumor cells in the original tumor bed.

Results

In the retrospective cohort (n = 69) 62.3% of the specimens were classified as stroma-rich. In univariate analysis TSR was significantly associated with radiological response (76.0% stroma-poor vs. 48.8% stroma-rich, P = 0.03). This finding persisted after multivariate analysis for T-status, N-status and ER-status (Odds Ratio [OR] 0.17, 95% C.I.: 0.04-0.78). In the validation set, in which 47.9% of the specimens were stroma-rich (211 cases evaluated), TSR did not predict for radiological response (79.5% stroma-poor vs. 79.2%, P = 0.96). However, when validation data were split on basis of ER-status, TSR was a significant and independent predictor for radiological response in ER-negative pts. (89.5% vs. 50%, P = 0.048, 95% C.I.: 0.01 - 0.98). In the validation set, TSR predicted for pCR with greater pCR rates in stroma-poor tumors (P = 0.03, 22.7% vs 10.3%). Final response results of the pilot and the enlarged sample size of all 250 pts of the validation set will be presented.

Conclusions

TSR might be a marker for radiological and pathological response to neoadjuvant chemotherapy, especially for the ER- tumor subgroup. Considering the simplicity and low cost of TSR assessment, it should be further evaluated and will be prospectively studied in the next neoadjuvant chemotherapy trial of the BOOG.

Contact information:

Dr. J.R. Kroep, M.D., Ph.D., Department of Medical Oncology, email:j.r.kroep@lumc.nl or T.J.A. Dekker, MSc. Department of Surgery and Medical Oncology, email: t.j.a.dekker@lumc.nl or LUMC datacenter, Department of Surgery, phone +31(0)71-5263500, fax +31(0)71-5266744, email: datacenter@lumc.nl, Leiden University Medical Center (LUMC), Leiden, The Netherlands.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-06-04.

Excellent prognosis of node negative patients after sentinel node procedure in colon carcinoma: a 5-year follow-up study

AIM

Investigate the prognostic impact and clinical relevance of the sentinel node (SN)-procedure in colon carcinoma.

PATIENTS AND METHODS

Between May 2002 and January 2004, the SN-procedure was performed in 55 patients that underwent elective resection for clinically non-advanced colon carcinoma. A control group of 110 patients was identified from a cohort between January 2000 and April 2002. All lymph nodes were analysed by conventional haematoxylin-eosin staining. All negative SNs underwent in-depth analysis using immunohistochemical-staining and automated microscopy with the Ariol-system. Patients with positive lymph nodes were offered adjuvant chemotherapy. All patients were routinely monitored at 6-month intervals and follow-up was more than 5 years.

RESULTS

The SN was successfully identified in 98% of the patients, with 94% sensitivity. In-depth analysis with immunohistochemistry and automated microscopy (Ariol-system) upstaged 3 and 4 patients respectively. When only node-negative patients were analysed, overall 5-year-survival was significantly better in the SN group (91% vs. 76%, p = 0.04). Cancer-specific-mortality was even 0% (vs. 8%, p = 0.08). Disease-free-survival was significantly improved to 96% (vs. 77%, p < 0.01).

CONCLUSIONS

This study describes the prognostic impact of the SN-procedure in colon carcinoma after 5-year-follow-up. Only one patient had recurrent disease after a negative SN procedure (disease-free-survival 96%). These results indicate that the SN-procedure is of prognostic relevance and might be useful to select patients for adjuvant chemotherapy. Patients that are lymph node negative after an SN-procedure have an excellent prognosis and do not need adjuvant treatment.

Quantitative assessment of lymph vascular space invasion (LVSI) provides important prognostic information in node-negative breast cancer

BACKGROUND

Some studies investigating the prognostic value of lymph vascular space invasion (LVSI) have shown an association between LVSI and disease-free survival. Definitive criteria and optimal determination of this parameter remain unclear, however, especially regarding the clinical relevance of LVSI quantification.

PATIENTS AND METHODS

A subset of node-negative breast carcinomas from premenopausal patients from the European Organization for the Research and Treatment of Cancer trial 10854 (assessing efficacy of perioperative chemotherapy patients with T1-T3, N0-2, and M0 breast cancer (BC) was selected and scored for LVSI. In 358 evaluable breast carcinomas, the number of LVSI foci and tumor cells was determined in the largest tumor embolus within the lymph vessels. These two parameters were multiplied to calculate the LVSI tumor burden (LVSI TB). The optimal cutoff for this parameter was calculated in a test set (N = 120), tested in a validation set (N = 238), and compared with simple quantitation of the number of LVSI foci.

RESULTS

Tumors with a single LVSI focus are not associated with increased risk for relapse [hazard ratio (HR) 1.423, 95% confidence interval (CI) 0.762-2.656]. The LVSI TB had higher sensitivity and specificity compared with simple determination of the number of LVSI foci. LVSI TB was independently associated with disease-free survival in the validation set (HR 2.366, 95% CI 1.369-4.090, P = 0.002) in multivariate analysis and provided prognostic information in both the low- and high-risk node-negative BC groups (P < 0.001 and P = 0.007, respectively).

CONCLUSION

The determination of the number of LVSI foci multiplied by the number of tumor cells gives the most reliable quantitative assessment of this parameter, which can provide prognostic information in node-negative BC.

Anastomotic leakage as an outcome measure for quality of colorectal cancer surgery

INTRODUCTION

When comparing mortality rates between hospitals to explore hospital performance, there is an important role for adjustment for differences in case-mix. Identifying outcome measures that are less influenced by differences in case-mix may be valuable. The main goal of this study was to explore whether hospital differences in anastomotic leakage (AL) and postoperative mortality are due to differences in case-mix or to differences in treatment factors.

METHODS

Data of the Dutch Surgical Colorectal Audit were used. Case-mix factors and treatment-related factors were identified from the literature and their association with AL and mortality were analysed with logistic regression. Hospital differences in observed AL and mortality rates, and adjusted rates based on the logistic regression models were shown. The reduction in hospital variance after adjustment was analysed with Levene's test for equality of variances.

RESULTS

17 of 22 case-mix factors and 4 of 11 treatment factors related to AL derived from the literature were available in the database. Variation in observed AL rates between hospitals was large with a maximum rate of 17%. This variation could not be attributed to differences in case-mix but more to differences in treatment factors. Hospital variation in observed mortality rates was significantly reduced after adjustment for differences in case-mix.

CONCLUSIONS

Hospital variation in AL is relatively independent of differences in case-mix. In contrast to 'postoperative mortality' the observed AL rates of hospitals evaluated in our study were only slightly affected after adjustment for case-mix factors. Therefore, AL rates may be suitable as an outcome indicator for measurement of surgical quality of care.

Genome-wide association studies identify four ER negative-specific breast cancer risk loci

Estrogen receptor (ER)-negative tumors represent 20-30% of all breast cancers, with a higher proportion occurring in younger women and women of African ancestry. The etiology and clinical behavior of ER-negative tumors are different from those of tumors expressing ER (ER positive), including differences in genetic predisposition. To identify susceptibility loci specific to ER-negative disease, we combined in a meta-analysis 3 genome-wide association studies of 4,193 ER-negative breast cancer cases and 35,194 controls with a series of 40 follow-up studies (6,514 cases and 41,455 controls), genotyped using a custom Illumina array, iCOGS, developed by the Collaborative Oncological Gene-environment Study (COGS). SNPs at four loci, 1q32.1 (MDM4, P = 2.1 × 10(-12) and LGR6, P = 1.4 × 10(-8)), 2p24.1 (P = 4.6 × 10(-8)) and 16q12.2 (FTO, P = 4.0 × 10(-8)), were associated with ER-negative but not ER-positive breast cancer (P > 0.05). These findings provide further evidence for distinct etiological pathways associated with invasive ER-positive and ER-negative breast cancers.

Hospital variation in failure to rescue after colorectal cancer surgery: results of the Dutch Surgical Colorectal Audit

BACKGROUND

Postoperative mortality is frequently used in hospital comparisons as marker for quality of care. Differences in mortality between hospitals may be explained by varying complication rates. A possible modifying factor may be the ability to let patients with a serious complication survive, referred to as failure to rescue (FTR). The purpose of this study was to evaluate how hospital performance on postoperative mortality is related to severe complications or to FTR and to explore the value of FTR in quality improvement programs.

METHODS

All patients operated for colorectal cancer from 2009 to 2011, registered in the Dutch Surgical Colorectal Audit, were included. Logistic regression models were used to obtain adjusted mortality, complication, and FTR rates. Hospitals were grouped into 5 quintiles according to adjusted mortality. Outcomes were compared between quintiles.

RESULTS

A total of 24,667 patients were included. Severe complications ranged from 19 % in the lowest to 25 % in the highest mortality quintile (odds ratio 1.5, 95 % confidence interval 1.37-1.67). Risk-adjusted FTR rates showed a marked difference between the quintiles, ranging from 9 % to 26 % (odds ratio 3.0, 95 % confidence interval 2.29-3.98). There was significant variability in FTR rates. Seven hospitals had significantly lower FTR rates than average.

CONCLUSIONS

High-mortality hospitals had slightly higher rates of severe complications than low-mortality hospitals. However, FTR was three times higher in high-mortality hospitals than in low-mortality hospitals. In quality improvement projects, feedback to hospitals of FTR rates, along with complication rates, may illustrate shortcomings (prevention or management of complications) per hospital, which may be an important step in reducing mortality.

The prognostic role of TGF-β signaling pathway in breast cancer patients

BACKGROUND

The transforming growth factor-β (TGF-β) pathway has dual effects on tumor growth. Seemingly, discordant results have been published on the relation between TGF-β signaling markers and prognosis in breast cancer. Improved prognostic information for breast cancer patients might be obtained by assessing interactions among TGF-β signaling biomarkers.

PATIENTS AND METHODS

The expression of nuclear Smad4, nuclear phosphorylated-Smad2 (p-Smad2), and the membranous expression of TGF-β receptors I and II (TβRI and TβRII) was determined on a tissue microarray of 574 breast carcinomas. Tumors were stratified according to the Smad4 expression in combination with p-Smad2 expression or Smad4 in combination with the expression of both TGF-β receptors.

RESULTS

Tumors with high expression of TβRII, TβRI and TβRII, and p-Smad2 (P = 0.018, 0.005, and 0.022, respectively), and low expression of Smad4 (P = 0.005) had an unfavorable prognosis concerning progression-free survival. Low Smad4 expression combined with high p-Smad2 expression or low expression of Smad4 combined with high expression of both TGF-β receptors displayed an increased hazard ratio of 3.04 [95% confidence interval (CI) 1.390-6.658] and 2.20 (95% CI 1.464-3.307), respectively, for disease relapse.

CONCLUSIONS

Combining TGF-β biomarkers provides prognostic information for patients with stage I-III breast cancer. This can identify patients at increased risk for disease recurrence that might therefore be candidates for additional treatment.

Nonelective colon cancer resections in elderly patients: results from the dutch surgical colorectal audit

AIMS

The aim of the study was to assess which factors contribute to postoperative mortality, especially in elderly patients who undergo emergency colon cancer resections, using a nationwide population-based database.

METHODS

6,161 patients (1,172 nonelective) who underwent a colon cancer resection in 2010 in the Netherlands were included. Risk factors for postoperative mortality were investigated using a multivariate logistic regression model for different age groups, elective and nonelective patients separately.

RESULTS

For both elective and nonelective patients, mortality risk increased with increasing age. For nonelective elderly patients (80+ years), each additional risk factor increased the mortality risk. For a nonelective patient of 80+ years with an American Society of Anesthesiologists score of III+ and a left hemicolectomy or extended resection, postoperative mortality rate was 41% compared with 7% in patients without additional risk factors.

CONCLUSIONS

For elderly patients with two or more additional risk factors, a nonelective resection should be considered a high-risk procedure with a mortality risk of up to 41%. The results of this study could be used to adequately inform patient and family and should have consequences for composing an operative team.

Increasing prevalence of comorbidity in patients with colorectal cancer in the South of the Netherlands 1995-2010

Comorbidity has large impact on colorectal cancer (CRC) treatment and outcomes and may increase as the population ages. We aimed to evaluate the prevalence and time trends of comorbid diseases in patients with CRC from 1995 to 2010. The Eindhoven Cancer Registry registers comorbidity in all patients with primary CRC in the South of the Netherlands. We analyzed the prevalence of serious comorbid diseases in four time frames from 1995 to 2010. Thereby, we addressed its association with age, gender and socio-economic status (SES). The prevalence of comorbidity was registered in 27,339 patients with primary CRC. During the study period, the prevalence of comorbidity increased from 47% to 62%, multimorbidity increased from 20% to 37%. Hypertension and cardiovascular diseases were most prevalent and increased largely over time (respectively 16-29% and 12-24%). Pulmonary diseases increased in women, but remained stable in men. Average age at diagnosis increased from 68.3 to 69.5 years (p = 0.004). A low SES and male gender were associated with a higher risk of comorbidity (not changing over time). This study indicates that comorbidity among patients with CRC is common, especially in males and patients with a low SES. The prevalence of comorbidity increased from 1995 to 2010, in particular in presumably nutritional diseases. Ageing, increased life expectancy and life style changes may contribute to more comorbid diseases. Also, improved awareness among health care providers on the importance of comorbidity may have resulted in better registration. The increasing burden of comorbidity in patients with CRC emphasizes the need for more focus on individualized medicine.

Focusing on desired outcomes of care after colon cancer resections; hospital variations in 'textbook outcome'

AIMS

We propose a summarizing measure for outcome indicators, representing the proportion of patients for whom all desired short-term outcomes of care (a 'textbook outcome') is realized. The aim of this study was to investigate hospital variation in the proportion of patients with a 'textbook outcome' after colon cancer resections in the Netherlands.

METHODS

Patients who underwent a colon cancer resection in 2010 in the Netherlands were included in the Dutch Surgical Colorectal Audit. A textbook outcome was defined as hospital survival, radical resection, no reintervention, no ostomy, no adverse outcome and a hospital stay < 14 days. We calculated the number of hospitals with a significantly higher (positive outlier) or lower (negative outlier) Observed/Expected (O/E) textbook outcome than average. As quality measures may be more discriminative in a low-risk population, analyses were repeated for low-risk patients only.

RESULTS

A total of 5582 patients, treated in 82 hospitals were included. Average textbook outcome was 49% (range 26-71%). Eight hospitals were identified as negative outliers. In these hospitals a 'textbook outcome' was realized in 35% vs. 52% in average hospitals (p < 0.01). In a sub-analysis for low-risk patients, only one additional negative outlier was identified.

CONCLUSIONS

The textbook outcome, representing the proportion of patients with a perfect hospitalization, gives a simple comprehensive summary of hospital performance, while preventing indicator driven practice. Therewith the 'textbook outcome' is meaningful for patients, providers, insurance companies and healthcare inspectorate.

Meta-analysis of the risk for anastomotic leakage, the postoperative mortality caused by leakage in relation to the overall postoperative mortality

BACKGROUND

Availability of anastomotic leakage rates and mortality rates following anastomotic leakage is essential when informing patients with rectal cancer preoperatively. We performed a meta-analysis of studies describing anastomotic leakage and the subsequent postoperative mortality in relation to the overall postoperative mortality after low anterior resection for rectal cancer.

METHODS

A systematic search was performed of the published literature. Data on the definition and incidence rate of AL, postoperative mortality caused by AL, and overall postoperative mortality were extracted. Data were pooled and a meta-analysis was performed.

RESULTS

Twenty-two studies with 10,343 patients in total were analyzed. Meta-analysis of the data showed an average AL rate of 9%, postoperative mortality caused by leakage of 0.7% and overall postoperative mortality of 2%. The studies showed variation in incidence, definition and measurement of all outcomes.

CONCLUSION

We found a considerable overall AL rate and a large contribution of AL to the overall postoperative mortality. The variability of definitions and measurement of AL, postoperative mortality caused by leakage and overall postoperative mortality may hinder providing reliable risk information. Large-scale audit programs may provide accurate and valid risk information which can be used for preoperative decision making.

The proportion of tumor-stroma as a strong prognosticator for stage II and III colon cancer patients: validation in the VICTOR trial

BACKGROUND

The intra-tumor stroma percentage in colon cancer (CC) patients has previously been reported by our group as a strong independent prognostic parameter. Patients with a high stroma percentage within the primary tumor have a poor prognosis.

PATIENTS AND METHODS

Tissue samples from the most invasive part of the primary tumor of 710 patients (52% Stage II, 48% Stage III) participating in the VICTOR trial were analyzed for their tumor-stroma percentage. Stroma-high (>50%) and stroma-low (≤50%) groups were evaluated with respect to survival times.

RESULTS

Overall and disease-free survival times (OS and DFS) were significantly lower in the stroma-high group (OS P<0.0001, hazard ratio (HR)=1.96; DFS P<0.0001, HR=2.15). The 5-year OS was 69.0% versus 83.4% and DFS 58.6% versus 77.3% for stroma-high versus stroma-low patients.

CONCLUSION

This study confirms the intra-tumor stroma ratio as a prognostic factor. This parameter could be a valuable and low cost addition to the TNM status and next to current high-risk parameters such as microsatellite instability status used in routine pathology reporting. When adding the stroma-parameter to the ASCO criteria, the rate of 'undertreated' patients dropped from 5.9% to 4.3%, the 'overtreated' increased with 6.8% but the correctly classified increased with an additional 14%.

Prognostic factors for locoregional recurrences in colon cancer

BACKGROUND

There is increased interest in locoregional recurrences of rectal cancer. Despite comparable locoregional recurrence rates in colon cancer, only a few studies on locoregional recurrences among colon cancer patients have been published. This study was designed to identify prognostic factors for locoregional recurrences among patients with colon cancer in the Netherlands.

METHODS

The study population was composed of patients who underwent radical surgical resections for invasive colon carcinoma, diagnosed in three regions of the Netherlands from 2000 to 2003. The Kaplan-Meier method was used to calculate 5-year locoregional recurrence rates (LRR). Conditional hazard rates were estimated by the life-table method. Multivariate Cox regression analyses were performed to identify prognostic factors and to calculate a Locoregional Recurrence Risk Score (LRRS).

RESULTS

In total 127 of 2,282 patients developed locoregional recurrences within 5 years (LRR 6.4%). The risk of developing a locoregional recurrence was highest at 0.5-1 year after surgery. Patients with left-sided tumors, T3-T4 tumors, and positive lymph nodes and those who did not receive adjuvant chemotherapy were more likely to develop locoregional recurrences. Four risk groups based on the LRRS were defined. Five-year LRR was 2.5% for the very low-risk group and 25.1% for the high-risk group.

CONCLUSIONS

Although the locoregional recurrence rate in this study was relatively low, it remains a considerable problem. Identifying individual patients who might benefit from adjuvant chemotherapy may reduce the locoregional recurrence rate.

S4-2: The Risk of Contralateral Breast Cancer in BRCA1/2 Carriers Compared to Non-BRCA1/2 Carriers in an Unselected Cohort

Background: Women who survived their first breast cancer have a higher risk to develop a new primary tumor in the contralateral breast than the risk of women in the general population to develop a first breast cancer. Especially women who carry a germline mutation in either the BRCA1 or the BRCA2 gene face a high lifetime risk of developing a synchronous or metachronous bilateral breast cancer. It is important to provide precise risk estimates of contralateral breast cancer and identify factors which predict the risk of CBC in this group of high risk women. To answer these questions, we looked at the effect of BRCA1/2-carriership and its interaction with other factors on the risk to develop a CBC in an unselected cohort of breast cancer patients. Materials and methods: We collected clinico-pathological, treatment and follow-up data for 4856 patients with unilateral, invasive breast cancer, diagnosed under the age of 50, between 1970 and 2003, in ten different hospitals throughout The Netherlands. Germline DNA was isolated from formalin-fixed paraffin-embedded tissue and patients were tested for the most prevalent pathogenic BRCA1 and BRCA2 mutations in The Netherlands. DNA and clinical data were coded before the analyses. All second primary breast tumors in the contralateral breast diagnosed more than 3 months after the diagnosis of the first breast cancer were considered as events. Preliminary results from life-table analysis and Cox Proportional Hazard models adjusted for age at diagnosis are shown here. Further statistical analyses will include competing risk analysis.

Results: In 4856 patients genotyped for BRCA1/2 mutations, 206 (4.2%) carriers were identified. During a median follow-up of 9.8 years (range 0–38), 9% of the patients developed a CBC, resulting in a cumulative 15-year risk for CBC of 10.4% (95% CI = 9.25−11.7) for non-carriers and 35.4% (95% CI = 25.9−46.9) for carriers of a BRCA1 or BRCA2 mutation (HR = 4.04 (95% CI = 2.88−5.68)). Patients carrying a BRCA1/2 mutation who were diagnosed under the age of 40 with their first breast cancer experienced a cumulative 15-year risk for CBC of 52.4% (95% CI = 36.4−70.3) versus 21.3% (95% CI = 12.0−36.0) in those over the age of 40 (HR = 0.30 (95% CI = 0.14−0.65)). Furthermore, BRCA1/2 mutation carriers with a triple negative first tumor had a cumulative risk for CBC of 43.6 (95% CI = 25.1−67.7), in contrast, BRCA1/2 mutation carriers with a non-triple negative first tumor had a cumulative risk for CBC of 13.4% (95% CI = 4.21−38.4) (HR = 0.24 (95% CI = 0.07−0.86)). Age at diagnosis and triple negative status were not found to be predictors of the risk of CBC in non-carriers (HR = 0.81 (95% CI = 0.53−1.24) and HR = 1.49 (95% CI = 0.91−2.41) respectively).

Discussion: In this study we identified subgroups of patients with a high risk to develop a CBC after their first breast cancer. Guidelines about treatment decisions and screening for follow-up should take into account these high risk subgroups to provide even better information and counseling for BRCA1/2 mutation carriers.

On behalf of more than 20 involved authors of the BOSOM study from 10 different hospitals and institutions throughout The Netherlands.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr S4-2.

Systematic review and meta-analysis of the volume-outcome relationship in pancreatic surgery

BACKGROUND

Many studies have shown lower mortality and higher survival rates after pancreatic surgery with high-volume providers, suggesting that centralization of pancreatic surgery can improve outcomes. The methodological quality of these studies is open to question. This study involves a systematic review of the volume-outcome relationship for pancreatic surgery with a meta-analysis of studies considered to be of good quality.

METHODS

A systematic search of electronic databases up to February 2010 was performed to identify all primary studies examining the effects of hospital or surgeon volume on postoperative mortality and survival after pancreatic surgery. All articles were critically appraised with regard to methodological quality and risk of bias. After strict inclusion, meta-analysis assuming a random-effects model was done to estimate the effect of higher surgeon or hospital volume on patient outcome.

RESULTS

Fourteen studies were included in the meta-analysis. The results showed a significant association between hospital volume and postoperative mortality (odds ratio 0.32, 95 per cent confidence interval 0.16 to 0.64), and between hospital volume and survival (hazard ratio 0.79, 0.70 to 0.89).The effect of surgeon volume on postoperative mortality was not significant (odds ratio 0.46, 0.17 to 1.26). Significant heterogeneity was seen in the analysis of hospital volume and mortality. Sensitivity analysis showed no correlation with the extent of risk adjustment or study country; after removing one outlier study, the result was homogeneous. The data did not suggest publication bias.

CONCLUSION

There was a consistent association between high hospital volume and lower postoperative mortality rates with improved long-term survival.

Molecular alterations associated with liver metastases development in colorectal cancer patients

Background:

Understanding the molecular biology of colorectal cancer (CRC) provides opportunities for effective personalised patient management. We evaluated whether chromosomal aberrations, mutations in the PI(3)K signalling pathway and the CpG-island methylator phenotype (CIMP) in primary colorectal tumours can predict liver metastases.

Methods:

Formalin-fixed paraffin-embedded material from primary colorectal tumours of three different groups were investigated: patients with CRC without metastases (M0, n=39), patients who were treated with hyperthermal intraperitoneal chemotherapy for CRC metastases confined to the peritoneum (PM, n=46) and those who had isolated hepatic perfusion for CRC metastases confined to the liver (LM, n=48).

Results:

All samples were analysed for DNA copy number changes, PIK3CA, KRAS, BRAF mutations, CIMP and microsatellite instability. The primary CRCs of the LM group had significantly higher frequency of amplified chromosome 20q (P=0.003), significantly fewer mutations in the PI(3)K signalling pathway (P=0.003) and fewer CIMP high tumours (P=0.05). There was a strong inverse correlation between 20q and the PI(3)K pathway mutations.

Conclusion:

The development of CRC liver metastases is associated with amplification of chromosome 20q and not driven by mutations in the PI(3)K signalling pathway.

Importance of the first postoperative year in the prognosis of elderly colorectal cancer patients

Background

Elderly colorectal cancer patients have worse prognosis than younger patients. Age-related survival differences may be cancer or treatment related, but also due to death from other causes. This study aims to compare population-based survival data for young (<65 years), aged (65–74 years), and elderly (≥75 years) colorectal cancer patients.

Methods

All patients operated for stage I–III colorectal cancer between 1991 and 2005 in the western region of The Netherlands were included. Crude survival, relative survival, and conditional relative survival curves, under the condition of surviving 1 year, were made for colon and rectal cancer patients separately. Furthermore, 30-day, 1-year, and 1-year excess mortality data were compared.

Results

A total of 9,397 stage I–III colorectal cancer patients were included in this study. Crude survival curves showed clear survival differences between the age groups. These age-related differences were less prominent in relative survival and disappeared in conditional relative survival (CRS). Only in stage III disease did elderly patients have worse CRS than young patients. Furthermore, significant age-related differences in 30-day and 1-year excess mortality were found. Thirty-day mortality vastly underestimated 1-year mortality for all age groups.

Conclusions

Elderly colorectal cancer patients who survive the first year have the same cancer-related survival as younger patients. Therefore, decreased survival in the elderly is mainly due to differences in early mortality. Treatment of elderly colorectal cancer patients should focus on perioperative care and the first postoperative year.

Associations of breast cancer risk factors with tumor subtypes: a pooled analysis from the Breast Cancer Association Consortium studies

BACKGROUND

Previous studies have suggested that breast cancer risk factors are associated with estrogen receptor (ER) and progesterone receptor (PR) expression status of the tumors.

METHODS

We pooled tumor marker and epidemiological risk factor data from 35,568 invasive breast cancer case patients from 34 studies participating in the Breast Cancer Association Consortium. Logistic regression models were used in case-case analyses to estimate associations between epidemiological risk factors and tumor subtypes, and case-control analyses to estimate associations between epidemiological risk factors and the risk of developing specific tumor subtypes in 12 population-based studies. All statistical tests were two-sided.

RESULTS

In case-case analyses, of the epidemiological risk factors examined, early age at menarche (≤12 years) was less frequent in case patients with PR(-) than PR(+) tumors (P = .001). Nulliparity (P = 3 × 10(-6)) and increasing age at first birth (P = 2 × 10(-9)) were less frequent in ER(-) than in ER(+) tumors. Obesity (body mass index [BMI] ≥ 30 kg/m(2)) in younger women (≤50 years) was more frequent in ER(-)/PR(-) than in ER(+)/PR(+) tumors (P = 1 × 10(-7)), whereas obesity in older women (>50 years) was less frequent in PR(-) than in PR(+) tumors (P = 6 × 10(-4)). The triple-negative (ER(-)/PR(-)/HER2(-)) or core basal phenotype (CBP; triple-negative and cytokeratins [CK]5/6(+) and/or epidermal growth factor receptor [EGFR](+)) accounted for much of the heterogeneity in parity-related variables and BMI in younger women. Case-control analyses showed that nulliparity, increasing age at first birth, and obesity in younger women showed the expected associations with the risk of ER(+) or PR(+) tumors but not triple-negative (nulliparity vs parity, odds ratio [OR] = 0.94, 95% confidence interval [CI] = 0.75 to 1.19, P = .61; 5-year increase in age at first full-term birth, OR = 0.95, 95% CI = 0.86 to 1.05, P = .34; obesity in younger women, OR = 1.36, 95% CI = 0.95 to 1.94, P = .09) or CBP tumors.

CONCLUSIONS

This study shows that reproductive factors and BMI are most clearly associated with hormone receptor-positive tumors and suggest that triple-negative or CBP tumors may have distinct etiology.

Variation in treatment and outcome of patients with rectal cancer by region, hospital type and volume in the Netherlands

BACKGROUND

Aim of this study was to describe treatment patterns and outcome according to region and hospital type and volume among patients with rectal cancer in the Netherlands.

METHODS

All patients with rectal carcinoma diagnosed in the period 2001-2006 were selected from the Netherlands Cancer Registry. Logistic regression analyses were performed to examine the influence of relevant factors on the odds of receiving preoperative radiotherapy and on the odds of postoperative mortality. Relative survival analysis was used to estimate relative excess risk of dying according to hospital type and volume.

RESULTS

In total, 16 039 patients were selected. Patients diagnosed in a teaching or university hospital had a lower odds (OR 0.85; 95% CI 0.73-0.99 and OR 0.70; 95% CI 0.52-0.92) and patients diagnosed in a hospital performing >50 resections per year had a higher odds (OR 1.95; 95% CI 1.09-1.76) of receiving preoperative radiotherapy. A large variation between individual hospitals in rates of preoperative radiotherapy and between Comprehensive Cancer Centre-regions in the administration of preoperative chemoradiation was revealed. Postoperative mortality was not correlated to hospital type or volume. Patients with T1-M0 tumours diagnosed in a hospital with >50 resections per year had a better survival compared to patients diagnosed in a hospital with <25 resections per year (RER 0.11; 95% CI 0.02-0.78).

CONCLUSION

This study demonstrated variation in treatment and outcome of patients with rectal cancer in the Netherlands, with differences related to hospital volume and hospitals teaching or academic status. However, variation in treatment patterns between individual hospitals proved to be much larger than could be explained by the investigated characteristics. Future studies should focus on the reasons behind these differences, which could lead to a higher proportion of patients receiving optimal treatment for their stage of the disease.

Large variation between hospitals and pathology laboratories in lymph node evaluation in colon cancer and its impact on survival, a nationwide population-based study in the Netherlands

BACKGROUND

adequate lymph node (LN) evaluation is important for planning treatment in patients with colon cancer. Aims of this study were to identify factors associated with adequate nodal examination and to determine its relationship with stage distribution and survival.

PATIENTS AND METHODS

data from patients with colon carcinoma stages I-III who underwent surgical treatment and diagnosed in the period 2000-2006 were retrieved from the Netherlands Cancer Registry. Multilevel logistic analysis was carried out to examine the influence of relevant factors on the number of evaluated LNs. The relationship with survival was analysed using Cox regression analysis.

RESULTS

the number of examined LN was determined for 30 682 of 33 206 tumours. Median number of evaluated LN was 8, ranging from 4 to 15 between pathology laboratories. Females, younger patients, right-sided pN+ tumours with higher pT stage and patients diagnosed in an academic centre were less likely to have nine or less LN evaluated. Unexplained variation between hospitals and pathology laboratories remained, leading to differences in stage distribution. With increasing number of evaluated LN, the risk of death decreased.

CONCLUSION

there was large diversity in nodal examination among patients with colon cancer, leading to differences in stage distribution and being associated with survival.

Management of isolated nonresectable liver metastases in colorectal cancer patients: a case-control study of isolated hepatic perfusion with melphalan versus systemic chemotherapy

BACKGROUND

To compare the median overall survival of patients with isolated nonresectable liver metastases in comparable groups of patients treated with either isolated hepatic perfusion (IHP) with melphalan or systemic chemotherapy.

PATIENTS AND METHODS

Colorectal cancer patients with isolated liver metastases, who underwent IHP, were included in this study. The control group consisted of a subgroup of colorectal cancer patients with liver metastases only, who were enrolled in the randomized CApecitabine, IRinotecan, Oxaliplatin (CAIRO) phase III study.

RESULTS

Ninety-nine patients were treated with IHP, and 111 patients were included in the control group. All patient characteristics were comparable except for age. Median follow-up was 78.1 months for IHP versus 54.7 months in the control group. Median overall survival was 25.0 [95% confidence interval (CI) 19.4-30.6] months for IHP and 21.7 (95% CI 19.6-23.8) months for systemic treatment and did not differ significantly (P = 0.29). Treatment-related mortality was 2% for the systemic treatment and 6% for IHP (P = 0.11).

CONCLUSION

Compared with a patient group with comparable characteristics treated with systemic chemotherapy, IHP does not provide a benefit in overall survival in patients with isolated nonresectable colorectal liver metastases. Currently, the use of IHP cannot be advocated outside the scope of clinical studies.

Transanal endoscopic microsurgery versus total mesorectal excision of T1 rectal adenocarcinomas with curative intention

PURPOSE

After total mesorectal excision (TME) for rectal cancer, pathology is standardized with margin status as a predictor for recurrence. This has yet to be implemented after transanal endoscopic microsurgery (TEM) and was investigated prospectively for T1 rectal adenocarcinomas.

PATIENTS AND METHODS

Eighty patients after TEM were compared to 75 patients after TME. The study protocol included standardized pathology. TEM patients were eligible when excision margins were negative.

RESULTS

TEM was safer than TME as reflected by operating time, blood loss, hospital stay, morbidity, re-operation rate and stoma formation (all P<0.001). Mortality after TEM was 0% and after TME 4%. At 5 years after TEM and TME, both overall survival (TEM 75% versus TME 77%, P=0.9) and cancer-specific survival (TEM 90% versus TME 87%, P=0.5) were comparable. Local recurrence rate after TEM was 24% and after TME 0% (HR 79.266, 95% CI, 1.208 to 5202, P<0.0001).

CONCLUSION

For T1 rectal adenocarcinomas TEM is much saver than TME and survival is comparable. After TEM local recurrence rate is substantial, despite negative excision margins.

Newly discovered breast cancer susceptibility loci on 3p24 and 17q23.2

Genome-wide association studies (GWAS) have identified seven breast cancer susceptibility loci, but these explain only a small fraction of the familial risk of the disease. Five of these loci were identified through a two-stage GWAS involving 390 familial cases and 364 controls in the first stage, and 3,990 cases and 3,916 controls in the second stage. To identify additional loci, we tested over 800 promising associations from this GWAS in a further two stages involving 37,012 cases and 40,069 controls from 33 studies in the CGEMS collaboration and Breast Cancer Association Consortium. We found strong evidence for additional susceptibility loci on 3p (rs4973768: per-allele OR = 1.11, 95% CI = 1.08-1.13, P = 4.1 x 10(-23)) and 17q (rs6504950: per-allele OR = 0.95, 95% CI = 0.92-0.97, P = 1.4 x 10(-8)). Potential causative genes include SLC4A7 and NEK10 on 3p and COX11 on 17q.