Histopathological response after preoperative radiochemotherapy in rectal carcinoma is associated with improved overall survival

Prognostic value of pathological tumor regression grade in locally advanced gastric cancer: New perspectives from a single-center experience

BACKGROUND AND OBJECTIVE

Perioperative chemotherapy (PC) with radical surgery represents the gold standard of treatment for resectable advanced gastric cancer (GC). The prognostic value of pathological tumor regression grade (TRG) induced by neoadjuvant chemotherapy (NACT) is not clearly established. This study aimed to investigate the correlation between TRG and survival in GC.

METHODS

Patients affected by advanced GC undergoing PC and radical surgery were considered. TRG was assessed for each patient according to Becker's grading system. The correlation between TRG and survival was investigated.

RESULTS

One-hundred patients were selected; 25 showed a good response (GR) (TRG 1a/1b), while 75 had a poor response (PR) (TRG 2/3) to NACT. GR patients showed better disease-free survival (DFS) (52 vs. 19 months, p < .001) and disease-specific survival (DSS) (57 vs. 25 months, p < .0001) when compared to PR patients. On univariate analysis, TRG, lymph node ratio (LNR), tumor size, grading, and post-neoadjuvant therapy TNM stage were significantly correlated with survival. On multivariate analysis, TRG, LNR and tumor size were independent prognostic factors for DFS and DSS.

CONCLUSIONS

TRG, LNR, and tumor size are independent prognostic factors for DFS and DSS in patients with advanced GC undergoing NACT.

Pathological Tumor Regression Grade Classifications in Gastrointestinal Cancers: Role on Patients' Prognosis

Preoperative chemotherapy or combined radiotherapy and chemotherapy (CRT), followed by surgery, represents the standard approach for locally advanced esophageal, gastric, and rectal carcinomas. To adequately evaluate the effects of neoadjuvant CRT in the resection specimens, several histopathologic tumor regression grade (TRG) scoring systems have been introduced into clinical practice. The primary goal of these TRG systems relies on a correct prognostic stratification of patients in the attempt to help clinical decision-making and influence surgical strategies, postoperative adjuvant therapies, and surveillance intensity. However, most TRG systems suffer from poor reproducibility and low interobserver concordance rates. Many efforts have been made in the identification of alternative, robust, simple, and universally accepted TRG scoring systems, which would help in the comparison of different treatment strategies and in the standardization of multimodal therapies. The aim of this review is to analyze the most commonly used TRG systems in gastrointestinal cancers highlighting their pitfalls and usefulness, depending on the tumor type.

Pathologic assessment of gastrointestinal tract and pancreatic carcinoma after neoadjuvant therapy

Neoadjuvant therapy is increasingly used to treat patients with a wide variety of malignancies. Histologic evaluation of treated specimens provides important prognostic information and may guide subsequent chemotherapy. Neoadjuvant therapy is commonly employed in the treatment of locally advanced rectal adenocarcinoma, hepatic colorectal metastases, esophageal/esophagogastric junction carcinoma, and pancreatic ductal adenocarcinoma. Numerous tumor regression schemes have been used in these tumors and standardized approaches to evaluate these specimens are needed. In this review, the various tumor regression scoring systems that have been used in these organs are described and their associations with clinical outcomes are discussed. Recommendations regarding how to handle and report the histologic findings in these resections specimens are provided.

Tumor regression grading of gastrointestinal cancers after neoadjuvant therapy

Neoadjuvant therapy has been successfully introduced in the treatment of locally advanced gastrointestinal malignancies, particularly esophageal, gastric, and rectal cancers. The effects of preoperative chemo- or radiochemotherapy can be determined by histopathological investigation of the resection specimen following this treatment. Frequent histological findings after neoadjuvant therapy include various amounts of residual tumor, inflammation, resorptive changes with infiltrates of foamy histiocytes, foreign body reactions, and scarry fibrosis. Several tumor regression grading (TRG) systems, which aim to categorize the amount of regressive changes after cytotoxic treatment in primary tumor sites, have been proposed for gastroesophageal and rectal carcinomas. These systems primarily refer to the amount of therapy-induced fibrosis in relation to the residual tumor (e.g., the Mandard, Dworak, or AJCC systems) or the estimated percentage of residual tumor in relation to the previous tumor site (e.g., the Becker, Rödel, or Rectal Cancer Regression Grading systems). TRGs provide valuable prognostic information, as in most cases, complete or subtotal tumor regression after neoadjuvant treatment is associated with better patient outcomes. This review describes the typical histopathological findings after neoadjuvant treatment, discusses the most commonly used TRG systems for gastroesophageal and rectal carcinomas, addresses the limitations and critical issues of tumor regression grading in these tumors, and describes the clinical impact of TRG.

Prognostic significance of tumour regression grade after neoadjuvant chemoradiotherapy for a cohort of patients with locally advanced rectal cancer: an 8-year retrospective single-institutional study

AIM

Locally advanced rectal cancer (LARC) is frequently treated with neoadjuvant chemoradiotherapy (NACRT) to reduce the risk of local recurrence and improve survival. Tumour response to NACRT is variable and may influence the prognosis after subsequent surgery. This study compared the prognostic values of tumour regression grade (TRG) and neoadjuvant pathological (ypTNM) downstaging in patients with Stage II and III rectal cancer treated with NACRT followed by curative surgery.

METHOD

This study included 185 patients with LARC treated with long-course radiotherapy (45 Gy in 25 fractions) plus 5-fluorouracil over 5 weeks between 2005 and 2013. We used multivariate analysis to assess the relationship of Dworak's five-tier TRG, ypTNM stage and ypTNM downstaging with clinicopathological factors, 5-year disease-free survival (DFS) and 5-year overall survival (OS).

RESULTS

Total regression (TRG4), good regression (TRG3), moderate regression (TRG2), minor regression (TRG1) and no regression (TRG0) were seen in 38 (20.6%), 65 (35.2%), 43 (23.2%), 28 (15.1%) and 11 (5.9%) patients, respectively. TNM downstaging following NACRT occurred in 109 (58.9%) patients. The 5-year DFS rates after NACRT for TRG0, TRG1, TRG2, TRG3 and TRG4 were 0%, 58.5%, 66.4%, 80.4% and 82.6%, respectively (P < 0.001). The ypTNM stage correlated with 5-year DFS (P = 0.004) but not 5-year OS (P = 0.075). Multivariate analysis demonstrated that TRG was related to both DFS and OS (P < 0.001).

CONCLUSION

TRG measured on a five-tier system was better than ypTNM stage for predicting outcome in patients with LARC treated with NACRT and surgery.

Anastomotic leakage after sphincter-sparing surgery in a young woman diagnosed with low rectal cancer - case report

Rectal cancer is the third most common site for cancer in the world, with a high morbidity and mortality. The new techniques for the treatment of low rectal cancer have been improved recently, allowing sphincter-sparing surgery to be available for more patients, with an optimal oncological and functional outcome. The most fundamental advance in rectal cancer surgery was the concept of total mesorectal resection (TME) introduced by Heald in 1982. Association with neoadjuvant radio-chemotherapy determines regression of the disease by “down staging” the tumors and allows for sphincter-sparing surgery to be performed, with low recurrence rate and increased overall survival. We present the case of 48-year old woman who had low rectal resection with colorectal anastomosis for middle rectal cancer. The patient had a BMI of 29, was hypertensive, had uterine fibroids and underwent neoadjuvant radiotherapy. During the 4th postoperative day the patient developed an anastomotic leakage grade B which was spontaneously closed on the 15th postoperative day. The patient did not manifest fever or any other symptoms. Normal bowel function resumed on the 5th postoperative day. No recurrence was detected at the one-year follow-up.

Emergency presenting colon cancer is an independent predictor of adverse disease-free survival

Twenty percent of colon cancers present as an emergency. However, the association between emergency presentation and disease-free survival (DFS) remains uncertain. Consecutive patients who underwent elective (CC) and emergent (eCC) resection for colon cancer were included in the analysis. Survival outcomes were compared between the 2 groups in univariate/multivariate analyses. A total of 439 patients underwent colonic resection for colon cancer during the interval 2000-2010; 97 (22.1%) presented as an emergency. eCC tumors were more often located at the splenic flexure (P = 0.017) and descending colon (P = 0.004). The eCC group displayed features of more advanced disease with a higher proportion of T4 (P = 0.009), N2 tumors (P < 0.01) and lymphovascular invasion (P< 0.01). eCC was associated with adverse locoregional recurrence (P = 0.02) and adverse DFS (P < 0.01 ) on univariate analysis. eCC remained an independent predictor of adverse locoregional recurrence (HR 1.86, 95% CI 1.50-3.30, P = 0.03) and DFS (HR 1.30, 95% CI 0.88-1.92, P = 0.05) on multivariate analysis. eCC was not associated with adverse overall survival and systemic recurrence. eCC is an independent predictor of adverse locoregional recurrence and DFS.

Pathologic response to neoadjuvant treatment in locally advanced rectal cancer and impact on outcome

BACKGROUND

Downstaging and pathologic complete response (pCR) after chemoradiotherapy (CRT) may improve progression-free survival and overall survival (OS) after curative therapy of locally advanced adenocarcinoma of rectum. The purpose of this study is to evaluate the pathologic response subsequent to neoadjuvant chemoradiation in locally advanced rectal adenocarcinoma and any impact of response on oncological outcome [disease-free survival (DFS), OS].

METHODS

A total of 127 patients with histologically-proven rectal adenocarcinoma, locally advanced, were treated with preoperative radiotherapy and concurrent 5-fluorouracil (5 FU), and followed by curative surgery. Pathologic response to neoadjuvant treatment was evaluated by comparing pathologic TN (tumour and nodal) staging (yp) with pre-treatment clinical staging. DFS and OS were compared in patients with: pCR, partial pathologic response and no response to neoadjuvant therapy.

RESULTS

14.96% (19 patients) had a pCR, 58.27% [74] showed downstaging and 26.77% [34] had no change in staging. At follow-up (range, 4-9 years, median 6 years 2 months or 74 months), 17.32% [22] showed recurrence: 15.74% [20] distant metastasis, 1.57% [2] pelvic failure. 10.5% [2] of the patients with pCR showed distant metastasis, none showed local recurrence. In the downstaged group, nine developed distant failure and two had local recurrence (14.86%). Distant failure was seen in 26.47% [9] of those with no response to neoadjuvant treatment. DFS and OS rates for all groups were 82.67% and 88.97% respectively. Patients with pCR showed 89.47% DFS and 94.7% OS. In partial responders, DFS was 85.1% and OS was 90.5%. In non-responders, DFS and OS were 73.5% and 82.3% respectively. Patients with pCR had a significantly greater probability of DFS and OS than non-responders. Rectal cancer-related death was 11.02% [14]: one patient (5.26%) with pCR, 9.47% [7] in the downstaged group and 17.64% [6] of non-responders.

CONCLUSIONS

The majority of patients showed some response to neoadjuvant treatment. Findings of this study indicate tumour response to neoadjuvant CRT improves the long-term outcome, with a better result in patients with pCR.

Preoperative Chemoradiation With VMAT-SIB in Rectal Cancer: A Phase II Study

PURPOSE

The aim of this study was to investigate the efficacy and toxicity of volumetric modulated arc therapy (VMAT)-simultaneous integrated boost (SIB) in preoperative combined treatment of locally advanced rectal cancer.

METHODS

Radiation therapy was performed using the VMAT-SIB technique. The dose to mesorectum and pelvic lymph nodes was 45 Gy (1.8 Gy/fraction). A concomitant boost was delivered on GTV + 2-cm margin with a total dose of 57.5 Gy (2.3 Gy/fraction). The following concomitant chemotherapy was administered: capecitabine (825 mg/m² twice daily, 5 days per week) and oxaliplatin (130 mg/m² on days 1, 17, and 35). Efficacy was evaluated in terms of complete pathological response (pCR). Acute toxicities were evaluated according to Common Terminology Criteria for Adverse Events version 3.0 criteria.

RESULTS

A total of 18 patients (7 women; median age 62 years; clinical stage: 4 local recurrences, 6 cT4, 5 cT3, 3 cT2, 2 cN0, 7 cN1, 9 cN2) were enrolled. Sixteen patients underwent surgical resection (9 low anterior resection, 6 abdominal perineal amputations; 1 transanal excision) and 2 patients did not undergo surgery for early metastatic progression or death from acute pulmonary edema. R0 resection was achieved in all patients who underwent surgery. Overall, 4 patients had a pCR and 7 patients only a microscopic residual of disease (pT0-Tmic: 11/18 = 61.1%; 95% CI, 36.2-86.1). Acute grade ≥ 3 toxicity was as follows: 1 case of leukopenia, 1 skin toxicity, 1 genitourinary toxicity, and 5 gastrointestinal toxicities, with an overall incidence of 8 (44.4%) of 18 patients. One-, 3-, and 5-year cumulative local control was 100%, 68.6%, and 68.6%, respectively. One-, 3-, and 5-year cumulative disease-free survival was 88.9%, 66.7%, and 66.7%, respectively. One-, 3-, and 5-year cumulative overall survival was 85%, 63.8%, and 63.8%, respectively.

CONCLUSION

The regimen used in this study showed excellent results in terms of pathologic responses. However, despite the use of the VMAT technique, more than one-third of patients had severe acute toxicity.

Tumor regression grade in gastric cancer: Predictors and impact on outcome

BACKGROUND

The clinical value and prognostic implications of histologic response to neoadjuvant chemotherapy in gastric cancer is unknown.

METHODS

Tumor regression grade (TRG) was recorded in 58 gastric cancer patients identified from two institutional surgical databases. TRG 1a/b represented histologic responders (<10% viable tumor), while TRG 2/3 represented non-responders (>10% viable tumor).

RESULTS

TRG 1a/b was recorded in 10 patients (17%), while 48 patients (83%) had a TRG 2/3 response. Larger tumor size (OR 0.24; 95%CI 0.09, 0.64; P = 0.004) and clinical downstaging (OR 30.0; 95%CI 3.26, 276; P = 0.003) were the only factors predictive of histologic response. TRG 1a/b responders had 3-year survival of 70.0% and an estimated overall survival of >69.8 months compared to 38.2% and 22.8 months in non-responders; however, this trend was not statistically significant (P = 0.535). While TRG could not predict survival (OR 2.40; 95%CI 0.46, 12.57; P = 0.300), patient age (OR 1.06; 95%CI 1.00, 1.11; P = 0.035), and the number of positive lymph nodes (≥7; OR 0.05; 95%CI 0.07, 0.27; P < 0.001) were independent predictors of survival.

CONCLUSIONS

Few gastric cancers demonstrate histologic response to neoadjuvant chemotherapy. While TRG may be a valid marker for treatment response, its predictive value and clinical application in gastric cancer remains unclear. J. Surg. Oncol. 2016;114:434-439. © 2016 Wiley Periodicals, Inc.

Lymphovascular invasion: a comprehensive appraisal in colon and rectal adenocarcinoma

BACKGROUND

Colon and rectal adenocarcinomas differ at a multitude of levels. The association between outcome and predictor in 1 group may obscure the relationship between outcome and predictor in the other.

OBJECTIVE

The current study aims to evaluate the prognostic properties of lymphovascular invasion in colon and rectal adenocarcinoma separately.

MATERIALS AND METHODS (DESIGN, SETTING AND PATIENTS)

A comparative retrospective analysis was undertaken to determine the prognostic properties of lymphovascular invasion in colon and rectal adenocarcinomas. Patients were classified as lymphovascular invasion positive and lymphovascular invasion negative in separate colon and rectal cancer cohorts. Within cohorts, a univariate analysis was undertaken to determine the association between lymphovascular invasion positivity and local/systemic recurrence and overall/disease-free survival. Findings were evaluated by using Kaplan-Meier estimates, log-rank analysis, and a Cox proportional hazards multivariate model.

MAIN OUTCOME MEASURE

The primary outcomes measured were overall and disease-free survival.

RESULTS

Five hundred twenty-seven patients were included in the analysis (379 with colon cancer and 148 with rectal cancer). On univariate analysis, lymphovascular invasion positivity was associated with adverse locoregional recurrence in colon (p = 0.002) but not rectal adenocarcinoma (p = 0.13). Conversely, lymphovascular invasion positivity was associated with adverse systemic recurrence in rectal (p = 0.002) but not colon adenocarcinoma (p = 0.35). On multivariate analysis, lymphovascular invasion positivity was an independent predictor of adverse disease-free survival in colon (p = 0.02) and rectal adenocarcinoma (p < 0.001). Regarding overall survival, lymphovascular invasion positivity was a poor prognostic indicator in rectal adenocarcinoma only (p = 0.04).

LIMITATIONS AND CONCLUSIONS

In this retrospective analysis, lymphovascular invasion positivity was associated with different patterns of disease recurrence in colon and rectal cancer. Lymphovascular invasion positivity was associated with adverse overall survival in rectal cancer only.

Comparison of (18)F-FDG PET/CT methods of analysis for predicting response to neoadjuvant chemoradiation therapy in patients with locally advanced low rectal cancer

PURPOSE

The aim of this study was to prospectively investigate the predictive value of (18)F-FDG PET/CT semiquantitative parameters for locally advanced low rectal cancer (LARC) treated by neoadjuvant chemoradiation therapy (nCRT).

METHODS

68 patients with LARC had (18)F-FDG PET/CT scans twice (baseline and 5-6 weeks post-nCRT). All patients underwent surgery with preservation of the sphincter 8 weeks later. (18)F-FDG PET/CT analysis was performed by visual response assessment (VRA) and semiquantitative parameters: SUVmax(baseline), SUVmean(baseline), MTV(baseline), TLG(baseline), SUVmax(post-nCRT), SUVmean(post-nCRT), MTV(post-nCRT), TLG(post-nCRT); ΔSUVmax and mean and Response indexes (RImax% and RImean%). Assessment of nCRT tumor response was performed according to the Mandard's Tumor Regression Grade (TRG) and (y)pTNM staging on the surgical specimens. Concordances of VRA with TRG, and with (y)pTNM criteria were evaluated by Cohen's K. Results were compared by t student test for unpaired groups. ROC curve analysis was performed.

RESULTS

VRA analysis of post-nCRT (18)F-FDG PET/CT scan for the (y)pTNM outcome showed sensitivity, specificity, accuracy, PPV, and NPV of 87.5%, 66.7%, 83.8%, 92.5%, and 53.3%, respectively. Concordances of VRA with TRG and with (y)pTNM were moderate. For the outcome variable TRG, the statistical difference between responders and non-responders was significant for SUVmax(post-nCRT) and RImean%; for the outcome variable (y)pTNM, there was a significant difference for MTV(baseline), SUVmax(post-nCRT), SUVmean(post-nCRT), MTV(post-nCRT), RImax%, and RImean%. ROC analysis showed better AUCs: for the outcome variable TRG for SUVmax(post-nCRT), SUVmean(post-nCRT), and RImean%; for the outcome variable (y)pTNM for MTVbaseline, SUVmax(post-nCRT), SUVmean(post-nCRT), MTV(post-nCRT), RImax%, and RImean%. No significant differences among parameters were found.

CONCLUSIONS

Qualitative and semiquantitative evaluations for (18)F-FDG PET/CT are the optimal approach; a valid parameter for response prediction has still to be established.

The value of liver-based standardized uptake value and other quantitative 18F-FDG PET-CT parameters in neoadjuvant therapy response in patients with locally advanced rectal cancer: correlation with histopathology

AIM

We aimed to investigate the value of PET-CT in therapy response and the correlation of quantitative PET parameters with histopathologic results in patients with locally advanced rectal cancer (LARC) before and after neoadjuvant chemoradiotherapy. We also analyzed the correlation of PET-CT parameters between Ki-67 and glucose transporter 1 (GLUT1).

PATIENTS AND METHODS

A total of 29 patients diagnosed with LARC who had undergone a biopsy between 2009 and 2012 were included in our study. Quantitative PET parameters [standardized uptake value (SUV)max-mean, lean body mass SUV(max-mean), tumor/liver SUV, retention index , and [INCREMENT]SUV(max)] were measured before and after therapy using PET-CT. Tumor regression grade (TRG) was evaluated according to Wheeler's classification. Patients in grade 1 were considered responders, whereas patients at grades 2 and 3 were considered nonresponders. Immunohistochemical staining with Ki-67 and GLUT1 was performed on biopsy and surgical specimens. The correlation between staining ratios and SUV was also investigated.

RESULTS

SUV parameters were significantly decreased after therapy (P < 0.001). Twelve (41%) patients were at TRG1, 10 (35%) were at TRG2, and seven (24%) were at TRG3. A cutoff SUV(max) of 5.05 to discriminate between responders and nonresponders after treatment revealed a sensitivity of 57%, specificity of 73%, negative predictive value of 65%, positive predictive value of 67%, and accuracy of 66%. Using a cutoff of 3.55 for the SUV(mean) (standardized measurement of SUV with 1.2-cm-diameter region of interest) revealed a sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of 67, 76, 67, 76, and 72%, respectively. For a cutoff of 1.95 for the tumor SUV(mean)/liver SUV(mean), these diagnostic values after therapy were 73, 78, 82, 67, and 76%, respectively. We found a moderate correlation between liver-based SUV(max) (r = -0.35, P = 0.019) and SUV(mean )(r = -0.31, P = 0.036) with GLUT1 after therapy. Quantitative PET parameters and retention index were moderately correlated with Ki-67.

CONCLUSION

PET-CT is a useful method for assessing the response to neoadjuvant chemoradiotherapy in patients with LARC. The most significant parameter for assessing treatment response using SUV parameters is the tumor/liver ratio.

The predictive value of 18F-FDG PET/CT for assessing pathological response and survival in locally advanced rectal cancer after neoadjuvant radiochemotherapy

PURPOSE

To evaluate whether metabolic changes in the primary tumour during and after preoperative radiochemotherapy (RCT) can predict the histopathological response in patients with locally advanced rectal cancer as well as disease-free survival (DFS) and overall survival (OS).

METHODS

Consecutive patients with cT2-4 N0-2 rectal adenocarcinoma were included. (18)F-FDG PET/CT was performed at baseline, at the end of the second week of RCT (early PET/CT) and before surgery (late PET/CT). The PET/CT results were compared with histopathological data (ypT0 N0 vs. ypT1-4 N0-2 as well as TRG1 vs.TRG2-5) and survival.

RESULTS

The study included 126 patients. Among 124 patients in whom TNM classification was available, 28 (22.6 %) were ypT0 N0, and among all 126 patients, 31 (24.6 %) were TRG1. The areas under the curve of the early response index (RI) for identifying non-complete pathological response (non-cPR) were 0.74 (95 % CI 0.61 - 0.87) for ypT1-4 N0-2 patients and 0.75 (95 % CI 0.62 - 0.88) for TRG2-5 patients. The optimal cut-off for differentiating patients with non-cPR and cPR was found to be a reduction of 61.2 % (83.1 % sensitivity and 65 % specificity in ypT1-4 N0-2 patients; 85.4 % sensitivity and 65.2 % specificity in TRG2-5 patients). The optimal cut-off for late RI could not be found. The qualitative analysis of images obtained after RCT demonstrated 81.5 % sensitivity and 61.3 % specificity in predicting TRG2-5. After a median follow-up of 68 months, the low number of patients with local/distant recurrence or who had died did not allow the value of PET/CT for predicting DFS and OS to be calculated.

CONCLUSION

The early assessment of response to RCT by (18)F-FDG PET/CT can predict non-cPR allowing practical modification of preoperative treatment. Conversely, late RI is not sufficiently accurate for guiding the decision as to whether local excision or even observation is appropriate in an individual patient. Qualitative analysis of late PET/CT images is also not sensitive enough alone to rule out the presence of residual disease.

Assessment of tumor regression of esophageal adenocarcinomas after neoadjuvant chemotherapy: comparison of 2 commonly used scoring approaches

Histopathologic determination of tumor regression provides important prognostic information for locally advanced gastroesophageal carcinomas after neoadjuvant treatment. Regression grading systems mostly refer to the amount of therapy-induced fibrosis in relation to residual tumor or the estimated percentage of residual tumor in relation to the former tumor site. Although these methods are generally accepted, currently there is no common standard for reporting tumor regression in gastroesophageal cancers. We compared the application of these 2 major principles for assessment of tumor regression: hematoxylin and eosin-stained slides from 89 resection specimens of esophageal adenocarcinomas following neoadjuvant chemotherapy were independently reviewed by 3 pathologists from different institutions. Tumor regression was determined by the 5-tiered Mandard system (fibrosis/tumor relation) and the 4-tiered Becker system (residual tumor in %). Interobserver agreement for the Becker system showed better weighted κ values compared with the Mandard system (0.78 vs. 0.62). Evaluation of the whole embedded tumor site showed improved results (Becker: 0.83; Mandard: 0.73) as compared with only 1 representative slide (Becker: 0.68; Mandard: 0.71). Modification into simplified 3-tiered systems showed comparable interobserver agreement but better prognostic stratification for both systems (log rank Becker: P=0.015; Mandard P=0.03), with independent prognostic impact for overall survival (modified Becker: P=0.011, hazard ratio=3.07; modified Mandard: P=0.023, hazard ratio=2.72). In conclusion, both systems provide substantial to excellent interobserver agreement for estimation of tumor regression after neoadjuvant chemotherapy in esophageal adenocarcinomas. A simple 3-tiered system with the estimation of residual tumor in % (complete regression/1% to 50% residual tumor/>50% residual tumor) maintains the highest reproducibility and prognostic value.

Human epidermal growth factor receptor-2 expression in locally advanced rectal cancer: association with response to neoadjuvant therapy and prognosis

The aim of this study was to determine whether pretreatment status of human epidermal growth factor receptor-2 (HER-2) could predict pathologic response to neoadjuvant chemoradiotherapy (nCRT) and outcomes for patients with locally advanced rectal cancer (LARC). A total of 119 patients diagnosed with LARC received standardized multimodal treatment. Their HER-2 status was determined in pretreatment biopsies by immunohistochemistry (IHC) and FISH. Tumor response was assessed in resected regimens using the tumor regression grade system and TNM staging system. Twenty-two cases in 119 patients assessed as IHC3+ or IHC2+ plus gene-amplified were determined as HER-2 positive. Positive HER-2 status was not associated with any pretreatment clinicopathologic parameters (P > 0.05). HER-2 status could not predict pathologic response to nCRT based on downstaging (P = 0.210) and tumor regression grade (P = 0.085) but it provides us with a trend that HER-2-positive tumors may be resistant to nCRT. Positive HER-2 status was significantly associated with poor 5-year disease-free survival (P = 0.015) and 5-year overall survival (P = 0.026). It can act as a worse prognostic factor for LARC patients.

Overall survival is improved in mucinous adenocarcinoma of the colon

INTRODUCTION

Debate persists regarding the relationship between mucin expression and outcome in colon cancer. This arises due to discrepancy in the definition of mucinous adenocarcinoma and the combination of both colon and rectal cancers in analyses. This study examines the relationship between increased mucin production and outcomes in colon cancer.

METHODS

Cases were classified according to the World Health Organization classification of mucinous adenocarcinoma of the colon. Accordingly, tumors were categorized as either (a) mucinous adenocarcinoma of the colon (greater than 50% of the extracellular matrix occupied by mucin) or (b) non-mucinous adenocarcinoma of the colon. Overall survival and disease-free survival were calculated. A stepwise Cox proportional hazards regression model was employed to determine the risk of death/disease recurrence. Kaplan-Meier estimates of overall survival and disease-free survival were plotted for each group and compared using a log-rank test.

RESULTS

On univariate analysis, mucinous adenocarcinoma was associated with reduced risk of death (P = 0.01). On multivariate analysis, mucinous adenocarcinoma was also associated with reduced risk of death (hazard ratio (HR) 0.33, 95% confidence interval (CI) 0.14-0.79, P = 0.01). Kaplan-Meier estimates confirmed improved rate of survival in the mucinous vs. non-mucinous group (P = 0.01). Mucinous adenocarcinoma did not affect disease-free survival (HR 0.75, 95% CI 0.46-1.21, P = 0.22). A comparison of Kaplan-Meier estimates for systemic recurrence demonstrated significant increases in systemic recurrence in the group with no mucin production (P = 0.04) but not for locoregional recurrence (P = 0.24).

CONCLUSIONS

Histopathological evidence of mucinous adenocarcinoma in colon cancer is associated with improved outcomes.

The role of perfusion effects in monitoring of chemoradiotherapy of rectal carcinoma using diffusion-weighted imaging

PURPOSE

The aim of this study was to characterize and understand the therapy-induced changes in diffusion parameters in rectal carcinoma under chemoradiotherapy (CRT). The current literature shows conflicting results in this regard. We applied the intravoxel incoherent motion model, which allows for the differentiation between diffusion (D) and perfusion (f) effects, to further elucidate potential underlying causes for these divergent reports.

MATERIALS AND METHODS

Eighteen patients with primary rectal carcinoma undergoing preoperative CRT were examined before, during, and after neoadjuvant CRT using diffusion-weighted imaging. Using the intravoxel incoherent motion approach, f and D were extracted and compared with postoperative tumor downstaging and volume.

RESULTS

Initial diffusion-derived parameters were within a narrow range (D1 = 0.94 ± 0.12 × 10(-3) mm(2)/s). At follow-up, D rose significantly (D2 = 1.18 ± 0.13 × 10(-3) mm(2)/s; P < 0.0001) and continued to increase significantly after CRT (D3 = 1.24 ± 0.14 × 10(-3) mm(2)/s; P < 0.0001). The perfusion fraction f did not change significantly (f1 = 9.4 ± 2.0%, f2 = 9.4 ± 1.7%, f3 = 9.5 ± 2.7%). Mean volume (V) decreased significantly (V1 = 16,992 ± 13,083 mm(3); V2 = 12,793 ± 8317 mm(3), V3 = 9718 ± 6154 mm(3)). T-downstaging (10:18 patients) showed no significant correlation with diffusion-derived parameters.

CONCLUSIONS

Conflicting results in the literature considering apparent diffusion coefficient (ADC) changes in rectal carcinoma under CRT for patients showing T-downstaging are unlikely to be due to perfusion effects. Our data support the view that under effective therapy, an increase in D/ADC can be observed.

Tumor regression grading of gastrointestinal carcinomas after neoadjuvant treatment

Multimodal therapy concepts have been successfully implemented in the treatment of locally advanced gastrointestinal malignancies. The effects of neoadjuvant chemo- or radiochemotherapy such as scarry fibrosis or resorptive changes and inflammation can be determined by histopathological investigation of the subsequent resection specimen. Tumor regression grading (TRG) systems which aim to categorize the amount of regressive changes after cytotoxic treatment mostly refer onto the amount of therapy induced fibrosis in relation to residual tumor or the estimated percentage of residual tumor in relation to the previous tumor site. Commonly used TRGs for upper gastrointestinal carcinomas are the Mandard grading and the Becker grading system, e.g., and for rectal cancer the Dworak or the Rödel grading system, or other systems which follow similar definitions. Namely for gastro-esophageal carcinomas these TRGs provide important prognostic information since complete or subtotal tumor regression has shown to be associated with better patient’s outcome. The prognostic value of TRG may even exceed those of currently used staging systems (e.g., TNM staging) for tumors treated by neoadjuvant therapy. There have been some limitations described regarding interobserver variability especially in borderline cases, which may be improved by standardization of work up of resection specimen and better training of histopathologic determination of regressive changes. It is highly recommended that TRG should be implemented in every histopathological report of neoadjuvant treated gastrointestinal carcinomas. The aim of this review is to disclose the relevance of histomorphological TRG to accomplish an optimal therapy for patients with gastrointestinal carcinomas.

Comparison between preoperative and postoperative concurrent chemoradiotherapy for rectal cancer: an institutional analysis

PURPOSE

To evaluate the treatment outcomes of preoperative versus postoperative concurrent chemoradiotherapy (CRT) on locally advanced rectal cancer.

MATERIALS AND METHODS

Medical data of 114 patients with locally advanced rectal cancer treated with CRT preoperatively (54 patients) or postoperatively (60 patients) from June 2003 to April 2011 was analyzed retrospectively. 5-Fluorouracil (5-FU) or a precursor of 5-FU-based concurrent CRT (median, 50.4 Gy) and total mesorectal excision were conducted for all patients. The median follow-up duration was 43 months (range, 16 to 118 months). The primary end point was disease-free survival (DFS). The secondary end points were overall survival (OS), locoregional control, toxicity, and sphincter preservation rate.

RESULTS

The 5-year DFS rate was 72.1% and 48.6% for the preoperative and postoperative CRT group, respectively (p = 0.05, the univariate analysis; p = 0.10, the multivariate analysis). The 5-year OS rate was not significantly different between the groups (76.2% vs. 69.0%, p = 0.23). The 5-year locoregional control rate was 85.2% and 84.7% for the preoperative and postoperative CRT groups (p = 0.98). The sphincter preservation rate of low-lying tumor showed significant difference between both groups (58.1% vs. 25.0%, p = 0.02). Pathologic tumor and nodal down-classification occurred after the preoperative CRT (53.7% and 77.8%, both p < 0.001). Acute and chronic toxicities were not significantly different between both groups (p = 0.10 and p = 0.62, respectively).

CONCLUSION

The results confirm that preoperative CRT can be advantageous for improving down-classification rate and the sphincter preservation rate of low-lying tumor in rectal cancer.

Radiotherapy response in microsatellite instability related rectal cancer

Preoperative radiotherapy may improve the resectability and subsequent local control of rectal cancers. However, the extent of radiation induced regression in these tumours varies widely between individuals. To date no reliable predictive marker of radiation sensitivity in rectal cancer has been identified. At the cellular level, radiation injury initiates a complex molecular network of DNA damage response (DDR) pathways that leads to cell cycle arrest, attempts at re-constituting the damaged DNA and should this fail, then apoptosis. This review presents the details which suggest the roles of DNA mismatch repair proteins, the lack of which define a distinct subset of colorectal cancers with microsatellite instability (MSI), in the DDR pathways. Hence routine assessment of the MSI status in rectal cancers may potentially serve as a predictor of radiotherapy response, thereby improving patient stratification in the administration of this otherwise toxic treatment.

Fifteen different 18F-FDG PET/CT qualitative and quantitative parameters investigated as pathological response predictors of locally advanced rectal cancer treated by neoadjuvant chemoradiation therapy

PURPOSE

The aim of this study was to correlate qualitative visual response and various PET quantification factors with the tumour regression grade (TRG) classification of pathological response to neoadjuvant chemoradiotherapy (CRT) proposed by Mandard.

METHODS

Included in this retrospective study were 69 consecutive patients with locally advanced rectal cancer (LARC). FDG PET/CT scans were performed at staging and after CRT (mean 6.7 weeks). Tumour SUVmax and its related arithmetic and percentage decrease (response index, RI) were calculated. Qualitative analysis was performed by visual response assessment (VRA), PERCIST 1.0 and response cut-off classification based on a new definition of residual disease. Metabolic tumour volume (MTV) was calculated using a 40 % SUVmax threshold, and the total lesion glycolysis (TLG) both before and after CRT and their arithmetic and percentage change were also calculated. We split the patients into responders (TRG 1 or 2) and nonresponders (TRG 3-5).

RESULTS

SUVmax MTV and TLG after CRT, RI, ΔMTV% and ΔTLG% parameters were significantly correlated with pathological treatment response (p < 0.01) with a ROC curve cut-off values of 5.1, 2.1 cm(3), 23.4 cm(3), 61.8 %, 81.4 % and 94.2 %, respectively. SUVmax after CRT had the highest ROC AUC (0.846), with a sensitivity of 86 % and a specificity of 80 %. VRA and response cut-off classification were also significantly predictive of TRG response (VRA with the best accuracy: sensitivity 86 % and specificity 55 %). In contrast, assessment using PERCIST was not significantly correlated with TRG.

CONCLUSION

FDG PET/CT can accurately stratify patients with LARC preoperatively, independently of the method chosen to interpret the images. Among many PET parameters, some of which are not immediately obtainable, the most commonly used in clinical practice (SUVmax after CRT and VRA) showed the best accuracy in predicting TRG.

Proposal for a multifactorial prognostic score that accurately classifies 3 groups of gastric carcinoma patients with different outcomes after neoadjuvant chemotherapy and surgery

OBJECTIVE

We have developed a multifactorial histopathological prognostic score (PRSC) for patients with gastric cancer treated with neoadjuvant chemotherapy before surgery for the accurate discrimination of patient subgroups with differing outcomes.

BACKGROUND

For patients with gastric cancer who undergo multimodal treatment, the postoperative staging classifications used for nontreated tumors may not accurately predict patient prognosis.

METHODS

We evaluated 428 gastric carcinoma specimens after a cisplatin-based chemotherapy. The factors for the Union for International Cancer Control/American Joint Committee on Cancer (UICC/AJCC) ypT-category, ypN-category, and histopathological tumor regression were assigned a value from 1 to 3 as follows: ypT0 to 2 = 1 point; ypT3 = 2 points; ypT4 = 3 points; ypN0 = 1 point; ypN1 to 2 = 2 points; ypN3a to 3b = 3 points; less than 10% residual tumor per tumor bed = 1 point; 10% to 50% residual tumor per tumor bed = 2 points; and greater than 50% residual tumor per tumor bed = 3 points. A 3-tiered PRSC based on the sum value was established (group A: 3-4 points; group B: 5-7 points; group C: 8-9 points) and was found to correlate with patient prognosis.

RESULTS

The PRSC showed a clear discrimination of 3 significantly different prognostic groups (group A: 76 patients; group B: 210 patients; group C: 142 patients; P < 0.001). In multivariate analyses, including the completeness of resection, tumor diameter, lymphatic vessel invasion, tumor grading, and Lauren classification, the PRSC was the only independent prognostic factor for overall survival (hazard ratio [HR] = 2.03; 95% confidence intervals [CI], 1.49-2.78; P < 0.001). It was slightly superior to the UICC/AJCC staging system (HR = 1.66; 95% CI, 1.20-2.27; P = 0.002) when analyzed with tumor regression as an additional independent factor (HR = 1.27; 95% CI, 1.01-1.62; P = 0.044) included in the analysis.

CONCLUSIONS

The proposed PRSC reveals the most accurate prediction of survival for patients with gastric carcinoma after neoadjuvant chemotherapy followed by surgery. The PRSC clearly identifies 3 subgroups with different prognoses and may be helpful for therapeutic decisions.

Diffusion-weighted imaging in rectal carcinoma patients without and after chemoradiotherapy: a comparative study with histology

Diffusion-weighted imaging (DWI) can be used to quantitatively assess functional parameters in rectal carcinoma that are relevant for prognosis and treatment response assessment. However, there is no consensus on the histopathological background underlying the findings derived from DWI. The aim of this study was to perform a comparison of DWI and histologic parameters in two groups of rectal carcinoma patients without (n=12) and after (n=9) neoadjuvant chemoradiotherapy (CRT). The intravoxel incoherent motion (IVIM) model was used to calculate the diffusion coefficient D and the perfusion fraction f in rectal carcinoma, the adjacent rectum and fat in the two patient groups. Immunohistological analysis was performed to assess the cellularity, vascular area fraction and vessel diameter for comparison and correlation. Out of 36 correlations between parameters from DWI and histology, four were found to be significant. In rectal carcinoma of patients without CRT, the diffusion D and the perfusion f correlated with the vascular area fraction, respectively, which could not be found in the group of patients who received CRT. Further correlations were found for the rectum and fat. Histological evaluation revealed significant differences between the tissues on the microscopic level concerning the cellular and vascular environment that influence diffusion and perfusion. In conclusion, DWI produces valuable biomarkers for diffusion and perfusion in rectal carcinoma and adjacent tissues that are highly dependent of the underlying cellular microenvironment influenced by structural and functional changes as well as the administered treatment, and consequently can be beyond histological ascertainability.

Early prediction of histopathological response of rectal tumors after one week of preoperative radiochemotherapy using 18 F-FDG PET-CT imaging. A prospective clinical study

BACKGROUND

Preoperative radiochemotherapy (RCT) is standard in locally advanced rectal cancer (LARC). Initial data suggest that the tumor's metabolic response, i.e. reduction of its 18 F-FDG uptake compared with the baseline, observed after two weeks of RCT, may correlate with histopathological response. This prospective study evaluated the ability of a very early metabolic response, seen after only one week of RCT, to predict the histopathological response to treatment.

METHODS

Twenty patients with LARC who received standard RCT regimen followed by radical surgery participated in this study. Maximum standardized uptake value (SUV-MAX), measured by PET-CT imaging at baseline and on day 8 of RCT, and the changes in FDG uptake (ΔSUV-MAX), were compared with the histopathological response at surgery. Response was classified by tumor regression grade (TRG) and by achievement of pathological complete response (pCR).

RESULTS

Absolute SUV-MAX values at both time points did not correlate with histopathological response. However, patients with pCR had a larger drop in SUV-MAX after one week of RCT (median: -35.31% vs -18.42%, p = 0.046). In contrast, TRG did not correlate with ΔSUV-MAX. The changes in FGD-uptake predicted accurately the achievement of pCR: only patients with a decrease of more than 32% in SUV-MAX had pCR while none of those whose tumors did not show any decrease in SUV-MAX had pCR.

CONCLUSIONS

A decrease in ΔSUV-MAX after only one week of RCT for LARC may be able to predict the achievement of pCR in the post-RCT surgical specimen. Validation in a larger independent cohort is planned.

TFAP2E-DKK4 and chemoresistance in colorectal cancer

BACKGROUND

Chemotherapy for advanced colorectal cancer leads to improved survival; however, predictors of response to systemic treatment are not available. Genomic and epigenetic alterations of the gene encoding transcription factor AP-2 epsilon (TFAP2E) are common in human cancers. The gene encoding dickkopf homolog 4 protein (DKK4) is a potential downstream target of TFAP2E and has been implicated in chemotherapy resistance. We aimed to further evaluate the role of TFAP2E and DKK4 as predictors of the response of colorectal cancer to chemotherapy.

METHODS

We analyzed the expression, methylation, and function of TFAP2E in colorectal-cancer cell lines in vitro and in patients with colorectal cancer. We examined an initial cohort of 74 patients, followed by four cohorts of patients (total, 220) undergoing chemotherapy or chemoradiation.

RESULTS

TFAP2E was hypermethylated in 38 of 74 patients (51%) in the initial cohort. Hypermethylation was associated with decreased expression of TFAP2E in primary and metastatic colorectal-cancer specimens and cell lines. Colorectal-cancer cell lines overexpressing DKK4 showed increased chemoresistance to fluorouracil but not irinotecan or oxaliplatin. In the four other patient cohorts, TFAP2E hypermethylation was significantly associated with nonresponse to chemotherapy (P<0.001). Conversely, the probability of response among patients with hypomethylation was approximately six times that in the entire population (overall estimated risk ratio, 5.74; 95% confidence interval, 3.36 to 9.79). Epigenetic alterations of TFAP2E were independent of mutations in key regulatory cancer genes, microsatellite instability, and other genes that affect fluorouracil metabolism.

CONCLUSIONS

TFAP2E hypermethylation is associated with clinical nonresponsiveness to chemotherapy in colorectal cancer. Functional assays confirm that TFAP2E-dependent resistance is mediated through DKK4. In patients who have colorectal cancer with TFAP2E hypermethylation, targeting of DKK4 may be an option to overcome TFAP2E-mediated drug resistance. (Funded by Deutsche Forschungsgemeinschaft and others.).

β-catenin and Her2/neu expression in rectal cancer: association with histomorphological response to neoadjuvant therapy and prognosis

BACKGROUND

Neoadjuvant treatment strategies have been developed to improve survival of patients with advanced rectal cancer. Since mainly patients with major histopathological response benefit from this therapy, predictive and prognostic markers are needed. We examined the association of β-catenin and Her2/neu protein expression with histopathologic response to neoadjuvant radiochemotherapy and prognosis in patients with locally advanced rectal cancer.

METHODS

Fifty-four patients (33 male; 21 female; median age 60.4 years) with locally advanced rectal cancer were included in this study. All patients received a neoadjuvant radiochemotherapy (50.4 Gy, 5-FU) followed by surgical resection. Histomorphologic regression was evaluated by Dworak and Cologne staging system. Major response was defined by Dworak classification when resected specimens contained less than 50% vital tumor cells (n = 14) and by Cologne grading system when resected specimens contained less than 10% vital tumor cells (n = 15). Intratumoral β-catenin (nuclear/membranous) and Her2/neu (cytoplasmatic/membranous) expression was determined by immunohistochemistry in pre- and post-therapeutic specimens and correlated with clinicopathologic parameters.

RESULTS

A significant association was detected between pre-therapeutic membranous β-catenin levels and response: patients with a lower β-catenin protein expression showed significantly more often a major response compared with patients having high intratumoral protein levels (p = 0.011). In addition, patients with a higher Her2/neu protein expression showed a significant survival benefit compared with patients having low intratumoral protein levels (5-year survival rate: 81% vs. low 41%; p = 0.023).

CONCLUSIONS

The pre-therapeutic β-catenin and Her2/neu protein expression seem to be valuable predictive and prognostic markers in the multimodality treatment of advanced rectal cancer.

The prognostic value of grade of regression and oncocytic change in rectal adenocarcinoma treated with neo-adjuvant chemoradiotherapy

BACKGROUND

Pathological staging and regression grading may affect the clinical outcome in rectal carcinoma patients treated with neoadjuvant chemoradiation (NACRT). Oncocytic change (OC) has also been described in the residual tumor. This study assesses the correlation of degree of pathological response and OC with clinical outcome.

METHODS

Seventy-five cases of rectal adenocarcinoma undergoing NACRT followed by surgery were retrospectively analyzed for preoperative and post-operative staging, degree of tumor response to NACRT using the Dworak Regression score (DR) and Tumor Regression Grading (TRG) systems, as well as the proportion of cells showing OC. These parameters were correlated with overall survival (OS) and disease-free survival (DFS).

RESULTS

Significant correlation was found between post-operative T and N stage and OS (P = 0.005 and 0.002, respectively); and post-operative and preoperative T stage with DFS (P = 0.002 and 0.02, respectively). Grouping patients by TRG scores (TRG1-3 vs TRG4-5) also proved to be a significant independent prognosticator for DFS (P < 0.001). The DR score groups and OC (<35% vs. >35%) were not statistically significant predictors of clinical outcome.

CONCLUSIONS

Post-NACRT T and N staging and the TRG system are important prognostic indicators. The presence and extent of OC needs to be better understood and further investigated.

Significance of histopathological tumor regression after neoadjuvant chemotherapy in gastric adenocarcinomas: a summary of 480 cases

OBJECTIVE

An increasing number of patients with locally advanced gastric carcinomas (GC) are being treated with preoperative chemotherapy before surgery.

BACKGROUND

Histopathological tumor regression may have an important prognostic impact in addition to the UICC-TNM classification system.

METHODS

We evaluated the histopathological tumor regression in 480 surgical resection specimens of GC after neoadjuvant cisplatin-based chemotherapy, using an established system encompassing three tumor regression grades based on the estimation of the percentage of residual tumor tissue at the primary tumor site in relation to the macroscopically identifiable former tumor bed. Tumor regression was correlated to clinicopathological characteristics and patient survival.

RESULTS

Of the patients in this study, 102 (21.2%) had complete or subtotal tumor regression (<10% residual tumor), 121 (25.2%) had partial tumor regression (10-50% residual tumor), and 257 (53.5%) had minimal or no regression (>50% residual tumor). Tumor regression was significantly associated with posttreatment tumor category (pT), lymph node status (pN), lymphatic invasion status (pL), and resection status (P < 0.001). Major histopathological regression was less frequent in tumors of the distal stomach and tumors of nonintestinal type (P = 0.003). Tumor regression (P = 0.009) and postoperative Lymph node status (P < 0.001) were independent prognostic factors for survival in a multivariate analysis of tumor regression, ypT/N/L category, resection status, grading and Lauren´s classification.

CONCLUSIONS

Assessment of histological tumor regression after preoperative chemotherapy in GC provides objective and highly valuable prognostic information in addition to posttherapeutic lymph node status. A standardized tumor regression grading system should be implemented in pathological reports of these tumors.

Histopathological regression grading versus staging of rectal cancer following radiotherapy

AIMS

To compare histological grading of rectal cancer radiotherapy response with pathological staging as a prognostic indicator.

METHODS

Histological tumour regression was five tier graded in 102 rectal cancer patients treated with preoperative radiotherapy [short course (n = 34), long course (n = 68)]. Differences between these grades and between the two radiotherapy regimes were assessed. These variables, pTMN staging and others were correlated with relapse free survival at 3 years.

RESULTS

22 patients suffered disease recurrence and four died during a mean post-operative follow-up of 40.3 months. There were 52 good responders (tumour regression grades 1-3) and 50 poor responders (tumour regression grades 4-5). Regression was greater following the long course regime (p < 0.0001). Otherwise, there were no significant differences between the response groups and between the two regimes, including the number of lymph nodes found in the resected bowel. Only the pN status correlated with relapse free survival on multivariate analysis (p = 0.0004; HR = 4.26, 95%CI = 1.66-10.93 for pN2 versus pN0).

CONCLUSIONS

The number of lymph nodes found for staging was not influenced by either the extent of primary tumour regression or the type of radiotherapy. pN status, but not tumour regression grade, is a reliable predictor of survival.

The severity of neural invasion is a crucial prognostic factor in rectal cancer independent of neoadjuvant radiochemotherapy

OBJECTIVE

To provide a comprehensive characterization of neural invasion (NI) in rectal adenocarcinoma (RC), to establish a novel NI-severity scoring system, and to assess the prognostic value of NI with emphasis on its localization and severity.

BACKGROUND

The literature merely contains small-scale studies with limited histopathological characterization of NI in RC.

METHODS

Neural invasion was thoroughly characterized in 296 patients with locally advanced uT3-RC (139 with primary resection and 157 with neoadjuvant radiochemotherapy [nRCTx]). To identify the precise localization of NI, we investigated the main tumor, peritumoral area, adjacent normal tissue, and all lymph nodes. To classify the clinical impact of NI, an NI severity score was established and related to patient prognosis.

RESULTS

Neural invasion was detected in 32% of patients with primary resection and in 19% (P = 0.010) receiving nRCTx. The major location of NI was found in the peritumoral area. The prevalence of NI in the main tumor within the primary resection group was 6%, whereas it was absent in the nRCTx group (P = 0.002). Increasing NI severity, but not NI localization, was associated with a significantly poorer survival and increased local recurrence rate in both groups. Multivariate analysis (including TNM-stage, grading, and Carcinoembryonic antigen (CEA)) revealed NI prevalence and severity as independent prognostic factors.

CONCLUSIONS

Neural invasion in RC has a heterogeneous appearance in regard to its localization and its severity. nRCTx seems to have a suppressive effect on NI. Neural invasion severity might be applied as a novel tool to estimate accurately patient's prognosis and thus should be considered in pathology reports.

Does a rectal cancer of the upper third behave more like a colon or a rectal cancer?

PURPOSE

This study aimed to evaluate whether cancers in the upper third of the rectum should be treated according to colon or rectal cancer guidelines.

METHODS

We evaluated 499 patients with tumors located in the sigmoid colon (299 patients, 60%), the upper third of the rectum (95 patients, 19%), or the middle third of the rectum (105 patients, 21%), International Union against Cancer tumor stage II or III, no preoperative radiochemotherapy, and primary curative tumor resection between 1990 and 2006. Patients' surgical, histopathological, and prognostic parameters were compared. The median follow-up time was 80 months.

RESULTS

Patients with sigmoid cancer showed a trend of significantly better estimated cause-specific survival (5-y value +/- 95% CI: 83.6 +/- 4.7%) compared with patients with rectal cancers of the upper third of the rectum (5-y value +/- 95% CI: 74.3 +/- 9.6%) or the middle third of the rectum (5-y value +/- 95% CI: 73.4 +/- 9.2%) (P = .063). Tumor location was an independent prognostic parameter (P = .036), with an increased risk of cause-specific death for rectal cancers of the upper third (hazard ratio, 1.87; P = .007) and of the middle third (hazard ratio, 1.43; P = .022) compared with sigmoid cancers. Stratification of upper third rectal cancers according to tumor grade, tumor infiltration depth (pT), and lymph node status (pN) identified a high-risk group.

CONCLUSIONS

Cancers of the upper third of the rectum have more similarities with rectal cancers of the middle third of the rectum than with sigmoid cancers. A subgroup of patients with upper third rectal cancer can be identified who may require a more aggressive therapy than only primary resection followed by adjuvant therapy.

Prognostic significance of histopathological tumor regression after neoadjuvant chemotherapy in esophageal adenocarcinomas

We evaluated histomorphological findings in 92 surgical resection specimens of locally advanced esophageal adenocarcinomas after neoadjuvant cisplatin-based chemotherapy. Tumor response to neoadjuvant chemotherapy was determined using a system encompassing three tumor regression grades based on the estimation of the percentage of residual tumor tissue of the primary tumor site in relation to the macroscopically identifiable previous tumor bed. The significance of this system was validated by correlation of the tumor regression grades with the corresponding clinicopathological characteristics and patient survival. Seven patients (7%) had complete tumor regression (grade tumor regression grade 1), 48 patients (52%) had subtotal or partial tumor regression (tumor regression grade 2: 1-50% residual tumor), and 37 patients (40%) had minimal or no regression (tumor regression grade 3: >50% residual tumor). Tumor regression was significantly associated with posttreatment complete tumor resection status (UICC R0 status; P=0.016), tumor category (UICC pT category; P<0.001), and with the absence of either lymph node metastases (P=0.001) or lymphatic invasion (P<0.001). Survival analysis showed a significant prognostic relevance of the applied regression system in univariate (P<0.001) and multivariate analyses as a single independent factor (P=0.024). We conclude that the effect of preoperative chemotherapy in esophageal adenocarcinomas can be assessed by the determination of histological tumor regression, providing highly valuable prognostic information, which may even exceed the prognostic impact of the current TNM classification of these tumors. Therefore, we strongly recommend the implementation of a standardized tumor regression grading system in pathological reports of esophageal adenocarcinomas treated by neoadjuvant chemotherapy.

Neoadjuvant chemoradiotherapy with capecitabine followed by laparoscopic resection in locally advanced tumors of middle and low rectum - toxicity and complications of the treatment

AIMS

The aim of this prospective study is to elucidate feasibility of protocol of neoadjuvant concomitant radiochemotherapy with capecitabine and long course radiotherapy with subsequent laparoscopic rectal resection. We assessed treatment toxicity, downstaging rate, pathological response to the neoadjuvant treatment, surgery complications, rate of conversions and sphincter-preserving surgical procedures, and intraoperative and early postoperative complications too.

METHODS

We acquired data of 78 patients from 1 January 2005 to 31 December 2007 with a locally advanced rectal cancer in our study. All patients were indicated for the neoadjuvant concomitant chemoradiotherapy due to locally advanced tumor (T3 or T4) or lymph nodes involvement suspicion (N+). Both radiotherapy (to pelvic region) and chemotherapy (capecitabine) were administered. Rectal tumors were localized within 12 cm from the anocutaneous verge. The average follow-up time was 23.9 months.

RESULTS

All patients completed their treatment according to the planned regimen and dose. The surgery was performed laparoscopicaly within 4-8 weeks following the concomitant chemoradiotherapy - in 17% cases was converted into conventional surgery. Downstaging was achieved in 69% of patients, pathological complete response in 10%, histologically negative lymph nodes were documented in 58% of patients. Grade 3 toxicity of the concomitant chemoradiotherapy was present in 3%; grade 2 in 29% of patients, particularly skin and gastrointestinal form. Intraoperative and early postoperative complications of the surgery were 18%. Re-operation was needed in 5% cases.

CONCLUSIONS

We demonstrated safety and low toxicity of the concomitant chemoradiotherapy with capecitabine.

Reduced lymph node yield in rectal carcinoma specimen after neoadjuvant radiochemotherapy has no prognostic relevance

BACKGROUND

In colorectal surgery UICC/AJCC criteria require a yield of 12 or more locoregional lymph nodes for adequate staging. Neoadjuvant radiochemotherapy for rectal carcinoma reduces the number of lymph nodes in the resection specimen; the prognostic impact of this reduced lymph node yield has not been determined.

METHODS

One hundred two patients with uT3 rectal carcinoma who were receiving neoadjuvant radiochemotherapy were compared with 114 patients with uT3 rectal carcinoma who were receiving primary surgery followed by adjuvant radiochemotherapy. Total lymph node yield and number of tumor-positive lymph nodes were determined and correlated with survival.

RESULTS

After neoadjuvant radiochemotherapy both total lymph node yield (12.9 vs. 21.4, p < 0.0001) and number of tumor-positive lymph nodes (1.0 vs. 2.3, p = 0.014) were significantly lower than after primary surgery plus adjuvant radiochemotherapy. Reduced total lymph node yield in neoadjuvantly treated patients had no prognostic impact, with overall survival of patients with 12 or more lymph nodes the same as that of patients with less than 12 lymph nodes. Overall survival of neoadjuvantly treated patients was significantly influenced by the number of tumor-positive lymph nodes with 5-year-survival rates of 88, 63, and 39% for 0, 1-3, and more than 3 positive lymph nodes (p < 0.0001).

CONCLUSION

The UICC/AJCC criterion of a total lymph node yield of 12 or more should be revised for rectal carcinoma patients.

Postoperative morbidity following chemoradiation for locally advanced low rectal cancer

BACKGROUND

Postoperative morbidity remains a significant clinical problem and may alter long-term outcome particularly after neoadjuvant chemoradiation in patients with locally advanced low rectal cancer. The aim of the present study was to identify a potential long-term effect of postoperative morbidity.

METHODS

Analysis of prospectively collected data of 90 consecutive patients who underwent neoadjuvant chemoradiation and curative mesorectal excision for locally advanced (cT3/4, Nx, M0/1) adenocarcinoma of the mid and lower third of the rectum during a 7-year period (1996-2002).

RESULTS

Major postoperative complications occurred in 17.8% and minor complications in 26.6% of patients. Hospital mortality and 30-day mortality was 0%. Infectious complications were seen in 34.5%. The leading causes of infectious complications were anastomotic leakage and perineal wound infection. Postoperative morbidity was statistically significantly associated with gender (P < 0.05), pre-therapeutic haemoglobin level (P < 0.05), ASA score (P < 0.05), hospitalisation (P < 0.001) and clinical long-time course (P < 0.01). Moreover, early postoperative morbidity was proven as an independent prognostic factor concerning disease-free (P < 0.05) and overall survival (P < 0.05).

CONCLUSION

Early postoperative morbidity in patients with preoperative chemoradiation due to locally advanced low rectal cancer is demonstrated as an independent prognosticator. Gender, pre-therapeutic haemoglobin level and ASA score indicate patients at risk for early postoperative complications and may therefore serve as predictive features.

Lymphatic vessel density as predictive marker for the local recurrence of rectal cancer

PURPOSE

This study identified possible factors affecting the frequency of local recurrence of rectal cancer, focusing on lymphangiogenesis as a predictor.

METHODS

We examined 352 primary rectal cancer cases and 34 local recurrent specimens by lymphatic hyaluronan receptor. The lymphangiogenesis of all specimens was evaluated by measuring by lymphatic vessel density and other clinicopathologic factors.

RESULTS

A multivariate analysis using the Cox proportional hazard model showed that lymphatic vessel density, lymph node metastasis, depth of invasion, and lymphatic invasion were significant independent predictive factors of local recurrence; lymphatic vessel density was the strongest predictor. In addition, a significant correlation was found between the lymphatic vessel density of the primary rectal cancer and the corresponding local recurrent cases.

CONCLUSIONS

We suggest that rectal cancers, which have active lymphangiogenesis, also demonstrate a greater potential for local recurrence, and the lymphatic vessel density of surgical specimens is an independent risk factor and a valuable predictive factor for the local recurrence of rectal cancer.

The predictive value of metabolic response to preoperative radiochemotherapy in locally advanced rectal cancer measured by PET/CT

BACKGROUND

To evaluate the value of positron emission tomography using fluorodeoxyglucose and computer tomography scan (FDG-PET/CT) for prediction of histopathological response of preoperative radiochemotherapy (RCTX) in patients with rectal carcinoma.

METHODS

Thirty patients with uT3 rectal carcinoma were examined by FDG-PET/CT at baseline, 14 days after initiation, and after completion of preoperative RCTX. The FDG decreases seen with PET scanning from baseline to day 14 (early metabolic response) and after completion of therapy (late metabolic response) were compared with histopathological tumor response. One patient denied surgery after RCTX.

RESULTS

The mean (+/-SD) reduction of tumor FDG uptake in histopathologically responding compared to non-responding tumors was -44.3% (+/-20.1%) versus -29.6% (+/-13.1%) (p = 0.085) at day 14 and -66.0% (+/-20.3%) versus -48.3% (+/-23.4%) (p = 0.040) after completion of RCTX. Best differentiation of histopathological tumor response was achieved by a cut-off value of 35% reduction of initial FDG uptake at day 14 and 57.5% after completion of therapy. Applying the cut-off values as a criterion for metabolic response, histopathological response was predicted with a sensitivity of 74% (14/19) at day 14 and 79% (15/19) after completion of therapy. The positive predictive value for early metabolic response was 82% (14/17) and for late metabolic response was 83% (15/18). Histopathological evidence of accumulated peritumoral inflammation cells was associated with a minor FDG decrease in five histopathologically responding patients, and influenced the results with negative predictive values of 58% (7/12) and 64% (7/11) at the early and late time points, respectively.

CONCLUSIONS

Metabolic response to a preoperative RCTX using FDG-PET/CT in rectal cancer patients can be correlated with histopathological response, but FDG uptake of peritumoral inflammation cells limited the results and led to false negative results.