KRAS Sequence Variation as Prognostic Marker in Patients With Young- vs Late-Onset Colorectal Cancer

Importance

The understanding of the association between KRAS sequence variation status and clinical outcomes in colorectal cancer (CRC) has evolved over time.

Objective

To characterize the association of age at onset, tumor sidedness, and KRAS sequence variation with survival among patients diagnosed with CRC.

Design, Setting, and Participants

This cross-sectional study used data extracted from the Surveillance, Epidemiology, and End Results database. Patients diagnosed with adenocarcinoma of the colon or rectum from 2010 through 2015 were included and were classified as having young-onset (YO) cancer if diagnosed between ages 20 to 49 years and late-onset (LO) cancer if diagnosed at age 50 years or older. Data were analyzed from April 2021 through August 2023.

Main Outcomes and Measures

CRC cause-specific survival (CSS) was summarized using Fine and Gray cumulative incidence and Kaplan-Meier curves. Estimation of subdistribution hazard ratios (sHRs) for the association of KRAS status, age at onset, and tumor location with CRC CSS was conducted using the Fine and Gray competing risk model. Cox proportional hazards regression was used to estimate and compare HRs.

Results

Among 21 661 patients with KRAS sequence variation status (mean [SD] age at diagnosis, 62.50 [13.78] years; 9784 females [45.2%]), 3842 patients had YO CRC, including 1546 patients with KRAS variants, and 17 819 patients had LO CRC, including 7311 patients with KRAS variants. There was a significant difference in median CSS time between patients with variant vs wild-type KRAS (YO: 3.0 years [95% CI, 2.8-3.3 years] vs 3.5 years [95% CI, 3.3-3.9 years]; P = .02; LO: 2.5 years [95% CI, 2.4-2.7 years] vs 3.4 years [95% CI, 3.3-3.6 years]; P < .001). Tumors with variant compared with wild-type KRAS were associated with higher risk of CRC-related death (YO: sHR, 1.09 [95% CI, 1.01-1.18]; P = .03; LO: sHR, 1.06 [95% CI, 1.02-1.09]; P = .002). Among patients with YO cancer, mortality hazards increased by location, from right (sHR, 1.02 [95% CI, 0.88-1.17) to left (sHR, 1.15 [95% CI, 1.02-1.29) and rectum (sHR, 1.16 [95% CI, 0.99-1.36), but no trend by tumor location was seen for LO cancer.

Conclusions and Relevance

In this study of patients diagnosed with CRC, KRAS sequence variation was associated with increased mortality among patients with YO and LO tumors. In YO cancer, variant KRAS-associated mortality risk was higher in distal tumors than proximal tumors.

Efficacy of different surgical treatments for management of anal fistula: a network meta-analysis

PURPOSE

Currently, the anal fistula treatment which optimises healing and preserves bowel continence remains unclear. The aim of our study was to compare the relative efficacy of different surgical treatments for AF through a network meta-analysis.

METHODS

Systematic searches of MEDLINE, EMBASE and CENTRAL databases up to October 2022 identified randomised controlled trials (RCTs) comparing surgical treatments for anal fistulae. Fistulae were classified as simple (inter-sphincteric or low trans-sphincteric fistulae crossing less than 30% of the external anal sphincter (EAS)) and complex (high trans-sphincteric fistulae involving more than 30% of the EAS). Treatments evaluated in only one trial were excluded from the primary analyses to minimise bias. The primary outcomes were rates of success in achieving AF healing and bowel incontinence.

RESULTS

Fifty-two RCTs were included. Of the 14 treatments considered, there were no significant differences regarding short-term (6 months or less postoperatively) and long-term (more than 6 months postoperatively) success rates between any of the treatments in patients with both simple and complex anal fistula. Ligation of the inter-sphincteric fistula tract (LIFT) ranked best for minimising bowel incontinence in simple (99.1% of comparisons; 3 trials, n = 70 patients) and complex anal fistula (86.2% of comparisons; 3 trials, n = 102 patients).

CONCLUSIONS

There is insufficient evidence in existing RCTs to recommend one treatment over another regarding their short and long-term efficacy in successfully facilitating healing of both simple and complex anal fistulae. However, LIFT appears to be associated with the least impairment of bowel continence, irrespective of AF classification.

Trends in Epidemiology of Esophageal Cancer in the US, 1975-2018

Importance

Esophageal cancer (EC) is the 7th most common cancer worldwide and 14th in the US. More data are needed to study the changing incidence patterns of its 2 primary histologic subtypes, squamous cell carcinoma of the esophagus (SCE) and adenocarcinoma of the esophagus (ACE).

Objective

To examine temporal trends in incidence rates of EC, ACE, and SCE from 1975 through 2018.

Design, Setting, and Participants

In this population-based cross-sectional study, data were derived from 9 Surveillance, Epidemiology, and End Results (SEER) registries from January 1975 through December 2018 and from all 21 registries for January 2000 through December 2018 for patients with a diagnosis of EC from 1975 through 2018 (International Classification of Disease-Oncology, Third Edition codes). Age-adjusted incidence rates (AAIRs) of EC, ACE, and SCE were calculated. The timing and magnitude of the annual percentage change (APC) in incidence were examined using Joinpoint regression analyses. Data analysis was started in 2021 and updated and completed in 2023.

Main Outcome and Measures

The APC for age-adjusted EC incidence rates as stratified by histology, anatomical location, stage, sex, age, race and ethnicity, and geographic region.

Results

A total of 47 648 patients with a diagnosis of EC were retained for analysis. These included 22 419 (47.1%) with a diagnosis of SCE, 22 217 (46.6%) with ACE, and 3012 (6.3%) with other subtypes. The AAIR for EC changed from 4.14 per 100 000 population in 1975 to 4.18 in 2018, AAIRs of SCE declined from 3.06 in 1975 to 1.15 in 2018 as well as for ACE, and AAIRs increased from 0.42 in 1975 to 2.78 in 2018. From 1975 through 2004, EC incidence significantly increased (APC, 0.53; 95% CI, 0.4 to 0.7) but significantly decreased (APC, -1.03; 95% CI, -1.3 to -0.7) from then until 2018. The APC of SCE significantly continued to decline (-2.80, 95% CI, -3.0 to -2.6), and ACE increased from 2000 to 2006 (APC, 2.51; 95% CI, 1.0 to 4.0) but has since stabilized from 2006 to 2018.

Conclusions and Relevance

The results of this cross-sectional study suggest that the incidence of EC modestly declined since 2004 and that the incidence of SCE continued to decline while the incidence rate of ACE plateaued for more than a decade. Understanding factors associated with plateaued rates of ACE may help inform public health interventions.

Changing epidemiology of esophageal cancer: A population-based study over 43 years (1975–2018)

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Background: Esophageal cancer (EC) is the seventh most common cancer worldwide. Previous studies have indicated that the incidence of squamous cell carcinoma of the esophagus (SCE) in the US has declined since the 1970s. In comparison, the incidence of adenocarcinoma of the esophagus (ACE) has sharply risen in the US since the 1970s. This study aimed to examine temporal trends in incidence rates of EC, ACE, and SCE that include recent decades. Methods: Data were derived from the Surveillance, Epidemiology, and End Results (SEER) of the National Cancer Institute - a population-based cancer database. Using SEER*Stat, we calculated the age-adjusted incidence rates (AAIR) for EC, ACE, and SCE in both SEER 9 (for longest follow-up time) and SEER 21 (the largest cohort covering 36.7% of the US population). Temporal incidence trends were examined using Joinpoint analyses to estimate the annual percent change (APC). Subgroup analyses were performed for sex, age, and race/ethnicity. Results: See Table. When stratified by age, age <64 years had a significant decrease in incidence with an APC of -1.1 (2007-2018), while the incidence plateaued in the remaining age groups. The rise in incidence was highest among non-Hispanic whites (NHW) from 2000-2004 (APC 4.0), especially NHW males (APC 3.0); however, the incidence plateaued in all race/ethnicity groups after 2006. Conclusions: The AAIR of EC as a whole has been decreasing since 2004. The AAIR of ACE has, for the first time, plateaued in the most recent decade (2006-2018), after having risen for three preceding decades (1975-2006); we find this effect is mainly driven by the AAIR from NHW males, age <64 years. The incidence of SCE has continued to decline since 1975. Future studies should further explore the underlying etiology of these patterns.[Table: see text]

Association of COVID-19 Vaccination With SARS-CoV-2 Infection in Patients With Cancer: A US Nationwide Veterans Affairs Study

Question

What is the effectiveness of SARS-CoV-2 vaccination in patients with cancer?

Findings

In this cohort study of US Veterans Affairs patients who received systemic therapy for cancer between August 15, 2010, and May 4, 2021, a proxy measure for effectiveness of the vaccine starting 14 days after the second dose was 58%. The measure of effectiveness starting 14 days after the second dose was 85% in patients who had not received systemic therapy within the 6 months prior to vaccination and 76% among those receiving hormonal treatment.

Meaning

Results suggest that SARS-CoV-2 vaccination associated with lower infection rates in patients with cancer, especially in those not receiving current systemic therapy and those receiving hormonal treatment.

Importance

Patients with cancer are at increased risk for severe COVID-19, but it is unknown whether SARS-CoV-2 vaccination is effective for them.

Objective

To determine the association between SARS-CoV-2 vaccination and SARS-CoV-2 infections among a population of Veterans Affairs (VA) patients with cancer.

Design, Setting, and Participants

Retrospective, multicenter, nationwide cohort study of SARS-CoV-2 vaccination and infection among patients in the VA health care system from December 15, 2020, to May 4, 2021. All adults with solid tumors or hematologic cancer who received systemic cancer-directed therapy from August 15, 2010, to May 4, 2021, and were alive and without a documented SARS-CoV-2 positive result as of December 15, 2020, were eligible for inclusion. Each day between December 15, 2020, and May 4, 2021, newly vaccinated patients were matched 1:1 with unvaccinated or not yet vaccinated controls based on age, race and ethnicity, VA facility, rurality of home address, cancer type, and treatment type/timing.

Exposures

Receipt of a SARS-CoV-2 vaccine.

Main Outcomes and Measures

The primary outcome was documented SARS-CoV-2 infection. A proxy for vaccine effectiveness was defined as 1 minus the risk ratio of SARS-CoV-2 infection for vaccinated individuals compared with unvaccinated controls.

Results

A total of 184 485 patients met eligibility criteria, and 113 796 were vaccinated. Of these, 29 152 vaccinated patients (median [IQR] age, 74.1 [70.2-79.3] years; 95% were men; 71% were non-Hispanic White individuals) were matched 1:1 to unvaccinated or not yet vaccinated controls. As of a median 47 days of follow-up, 436 SARS-CoV-2 infections were detected in the matched cohort (161 infections in vaccinated patients vs 275 in unvaccinated patients). There were 17 COVID-19–related deaths in the vaccinated group vs 27 COVID-19–related deaths in the unvaccinated group. Overall vaccine effectiveness in the matched cohort was 58% (95% CI, 39% to 72%) starting 14 days after the second dose. Patients who received chemotherapy within 3 months prior to the first vaccination dose were estimated to have a vaccine effectiveness of 57% (95% CI, –23% to 90%) starting 14 days after the second dose vs 76% (95% CI, 50% to 91%) for those receiving endocrine therapy and 85% (95% CI, 29% to 100%) for those who had not received systemic therapy for at least 6 months prior.

Conclusions and Relevance

In this cohort study, COVID-19 vaccination was associated with lower SARS-CoV-2 infection rates in patients with cancer. Some immunosuppressed subgroups may remain at early risk for COVID-19 despite vaccination, and consideration should be given to additional risk reduction strategies, such as serologic testing for vaccine response and a third vaccine dose to optimize outcomes.

Mobile health technology for remote home monitoring after surgery: a meta-analysis

BACKGROUND

Mobile health (mHealth) technology has been proposed as a method of improving post-discharge surveillance. Little is known about how mHealth has been used to track patients after surgery and whether its use is associated with differences in postoperative recovery.

METHODS

Three databases (PubMed, MEDLINE and the Cochrane Central Registry of Controlled Trials) were searched to identify studies published between January 1999 and February 2021. Mobile health was defined as any smartphone or tablet computer capable of electronically capturing health-related patient information and transmitting these data to the clinical team. Comparable outcomes were pooled via meta-analysis with additional studies compiled via narrative review. The quality of each study was assessed based on Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

Forty-five articles met inclusion criteria. While the majority of devices were designed to capture general health information, others were specifically adapted to the expected outcomes or potential complications of the index procedure. Exposure to mHealth was associated with fewer emergency department visits (odds ratio 0.42, 95 per cent c.i. 0.23 to 0.79) and readmissions (odds ratio 0.47, 95 per cent c.i. 0.29 to 0.77) as well as accelerated improvements in quality of life after surgery. There were limited data on other postoperative outcomes.

CONCLUSION

Remote home monitoring via mHealth is feasible, adaptable, and may even promote more effective postoperative care. Given the rapid expansion of mHealth, physicians and policymakers need to understand these technologies better so that they can be integrated into high-quality clinical care.

Digital healthcare technologies: Modern tools to transform prosthetic care

INTRODUCTION

Digital healthcare technologies are transforming the face of prosthetic care. Millions of people with limb loss around the world do not have access to any form of rehabilitative healthcare. However, digital technologies provide a promising solution to augment the range and efficiency of prosthetists.

AREAS COVERED

The goal of this review is to introduce the digital technologies that have the potential to change clinical methods in prosthetic healthcare. Our target audience are researchers who are unfamiliar with the field of prostheses in general, especially with the newest technological developments. This review addresses technologies for: scanning of amputated limbs, limb-to-socket rectification, additive manufacturing of prosthetic sockets, and quantifying patient response to wearing sockets. This review does not address biomechatronic prostheses or biomechanical design practices.

EXPERT OPINION

Digital technologies will enable affordable prostheses to be built on a scale larger than with today's clinical practices. Large technological gaps need to be overcome to enable the mass production and distribution of prostheses digitally. However, recent advances in computational methods and CAD/CAM technologies are bridging this gap faster than ever before. We foresee that these technologies will return mobility and economic opportunity to amputees on a global scale in the near future.

Treatment of Stage IV Colon Cancer in the United States: A Patterns-of-Care Analysis

BACKGROUND

National guidelines recommend chemotherapy as the mainstay of treatment for stage IV colon cancer, with primary tumor resection (PTR) reserved for patients with symptomatic primary or curable disease. The aims of this study were to characterize the treatment modalities received by patients with stage IV colon cancer and to determine the patient-, tumor-, and hospital-level factors associated with those treatments.

METHODS

Patients diagnosed with stage IV colon cancer in 2014 were extracted from the SEER Patterns of Care initiative. Treatments were categorized into chemotherapy only, PTR only, PTR + chemotherapy, and none/unknown.

RESULTS

The total weighted number of cases was 3,336; 17% of patients received PTR only, 23% received chemotherapy only, 41% received PTR + chemotherapy, and 17% received no treatment. In multivariable analyses, compared with chemotherapy only, PTR + chemotherapy was associated with being married (odds ratio [OR], 1.9), having bowel obstruction (OR, 2.55), and having perforation (OR, 2.29), whereas older age (OR, 5.95), Medicaid coverage (OR, 2.46), higher T stage (OR, 3.51), and higher N stage (OR, 6.77) were associated with PTR only. Patients who received no treatment did not have more comorbidities or more severe disease burden but were more likely to be older (OR, 3.91) and non-Hispanic African American (OR, 2.92; all P<.05). Treatment at smaller, nonacademic hospitals was associated with PTR (± chemotherapy).

CONCLUSIONS

PTR was included in the treatment regimen for most patients with stage IV colon cancer and was associated with smaller, nonacademic hospitals. Efforts to improve guideline implementation may be beneficial in these hospitals and also in non-Hispanic African American and older populations.

Racial disparity in KRAS mutation frequency and outcomes in colorectal cancer (CRC): A U.S. population based study

18

Background: Racial disparity in CRC survival outcome is well documented. Although the reasons for disparity are unclear, a combination of differences in access to care, quality of care, differential treatment response, and underlying cancer biology are implicated. Further, recent studies have observed differences in KRAS mutation frequency between race/ethnic groups. KRAS mutation in metastatic CRC portends a worse response to EGFR-directed therapy, and predicts a poorer prognosis. In this study, we examined whether racial/ethnic differences in KRAS mutation frequency might impact CRC outcomes on a population-based level. Methods: We examined data from 202,237 CRC patients in the Surveillance, Epidemiology, and End Results (SEER) registry between 2010 and 2015. The differences in tumor mutation status by stage and race/ethnicity were examined by χ2 testing. Cause-specific survival (CSS) and overall survival by mutation status were plotted by Kaplan-Meir curves. A multivariable Cox-proportional hazards model was used to construct hazard ratios and 95% confidence intervals (CI) using patient demographics, tumor characteristics, and KRAS mutation status. Results: Overall, about 9% of patients (n = 18,248) in the SEER registry had KRAS status available. In this cohort, tumors from Non-Hispanic Black (NHB) (48%) or Hispanic patients (44%) carried a greater KRAS mutation (mKRAS) rate when compared against Non-Hispanic White (NHW) (39%) or Asian or Pacific Islander (API) patients (37%) (p < 0.01). The assessment of the impact of mKRAS within each race/ethnic group, comparing patients with mKRAS versus wild-type KRAS (wKRAS) on CSS risk show a 7% risk increase for NHW, (HR = 1.07; 95%CI:1.02-1.12), a 15% risk increase for NHB, (HR = 1.15; 95%CI:1.04-1.26) and no significant increase among API, (HR = 1.02; 95%CI:0.92-1.4). Among patients with wKRAS, with NHW for reference, the risk of CSS is 11% higher among NHB (HR = 1.11; 95%CI:1.00-1.23), 14% higher for Hispanic, (HR = 1.14; 95%CI:1.02-1.26) and no significant difference observed among API, (HR = 1.03; 95%CI:0.91-1.16). Evaluation of the interaction between race/ethnicity and KRAS status on the CSS risk shows an increase of: 11% for mKRAS NHW, (HR = 1.11; 95%CI:1.00-1.23), 13% risk for NHB (HR = 1.13; 95%CI:1.01-1.25), 11% for Hispanic wKRAS, (HR = 1.11; 95%CI:1.04-1.18), 31% for Hispanic mKRAS (HR = 1.31; 95%CI:1.18-1.145), 16% for wKRAS API (HR = 1.16; 95%CI:1.03-1.29). In contrast, no significant difference in risk is seen for NHB nor API patients, HR = 1.02 (95%CI:0.90-1.14) and 1.04 (95%CI:0.91-1.20) respectively. Conclusions: mKRAS, compared to wKRAS, connotes worse CSS among NHW and NHB patients. Among wKRAS, NHB and Hispanic patients still experience higher mortality risk. This data suggests the negative prognosis heretofore associated with mKRAS may be linked to race/ethnicity and worthy of further study.

The impact of primary tumor location (PTL) and age on the risk of developing noncolonic second primary malignancy (SPM) in colon cancer (CC) patients (PTS)

67

Background: Colon cancer remains one of the leading causes of cancer death worldwide. There has been a renewing interest in the role of PTL (right- or RS vs. left-sided or LS) in CC for their differences in biology, prognostic and predictive features. Given the increasing incidence of early-onset (age 20-49) CC, coupled with their longer life expectancy, we seek to examine the effects of PTL and age in the development of SPM in a population-based cohort. Methods: Surveillance, Epidemiology, and End Results (SEER) Program data were queried to identify CC PTS diagnosed between 1973-2015 with complete follow-up information and available data on SPM. Using SEER*Stat, we calculated standardized incidence ratios (SIRs) -- the ratio of observed to expected cases of SPM based on incidence data in the general US population and compared by PTL (RS vs. LS) and age of diagnosis (20-49 vs. >49). Results: A total of 269,442 (RS/LS=46.4%/53.6%) CC PTS were obtained. Overall RS, compared with LS, CC PTS have a higher likelihood of developing SPM in all sites (OR: 1.09, 95% CI: 1.08- 1.11 vs. 1.03, 1.02-1.04). RS CC PTS and age 20-49 group, compared with other subgroups, has a much greater likelihood of being diagnosed with the following SPM:small intestine, urinary tract, bile duct, gynecologic (GYN), and stomach cancers, as shown in the Table below. Conclusions: Our results show that the increased risk in non-colonic SPMs in CC PTS is associated with RS CC and age less than 49, suggesting the implications on survivorship care and surveillance of SPMs. Furthermore, there may be a possible overlap with Lynch syndrome in these PTS with SPM given the overlap in the presentation of cancer patterns and early-onset of CC, suggesting the indication for MMR testing.

[Table: see text]

Small cell carcinoma of the kidney: a case report and analysis of data from the Surveillance, Epidemiology, and End Results registry

Background

Primary small cell carcinoma of the kidney is an extremely rare neoplasm. The clinical features of small cell carcinoma of the kidney are not well established due to its rarity and scarcity of case reports. We present an unusual case of small cell carcinoma of the kidney complicated by syndrome of inappropriate antidiuretic hormone secretion. We identify cases using a population-based dataset from the Surveillance, Epidemiology, and End Results registry and compare small cell carcinoma of the kidney with small cell carcinoma of the lung.

Case presentation

A 69-year-old Filipino man presented with hematuria for 1 month. A computed tomography scan demonstrated a large left kidney mass with biopsy demonstrating small cell carcinoma. Within 2 months he developed dizziness and was found to have a metastatic lesion to his brain. He was hyponatremic due to syndrome of inappropriate antidiuretic hormone secretion. He did not receive chemotherapy due to his poor functional status. He died within 8 months of presentation.

Results

From 1973 to 2013, 60 cases with small cell carcinoma of the kidney were identified in the Surveillance, Epidemiology, and End Results registry. Most (62%) presented with extensive stage, which occurred predominantly in white men in their seventh decade. The median overall survival with extensive stage small cell carcinoma of the kidney was 3 months versus 11 months with limited stage of small cell carcinoma of the kidney; this was worse than small cell carcinoma of the lung with a median survival of 5 and 13 months, respectively.

Conclusion

We present a rare case of small cell carcinoma of the kidney complicated by syndrome of inappropriate antidiuretic hormone secretion. This adds to our understanding of the clinical features of small cell carcinoma of the kidney. Furthermore, this is the first population-based study of small cell carcinoma of the kidney using the Surveillance, Epidemiology, and End Results database. Analysis shows that overall survival is worse in small cell carcinoma of the kidney relative to that of small cell carcinoma of the lung. Small cell carcinoma of the kidney presents very aggressively, and further studies are needed to develop a standard of care.

KRAS mutation as a predictor for cause-specific survival in early- versus late-onset colorectal cancer: A United States population-based study

580

Background: While the overall incidence rates for colorectal cancer (CRC) —the third leading cancer diagnosis in the U.S.—have been decreasing over the last several decades, incidence rates for early-onset (EO, age 20-49 years) CRC have shown an upward trend. Multiple studies have documented mutations in KRAS proto-oncogene (KRAS) as a poor prognostic factor in sporadic CRC, but its impact on EO versus late-onset (LO, age > 49 years) CRC is unclear. Methods: Surveillance, Epidemiology, and End Results (SEER) Program data were queried to identify pathologically-confirmed CRC cases tested for KRAS and diagnosed between 2010 and 2015. Demographic, histologic, and KRAS data were compared between EO and LO using Chi-square tests. Kaplan-Meier and Cox proportional hazards models were used to estimate cause-specific survival (CSS) and examine factors associated with CSS. Results: Of 202,173 CRC cases, 3,842 EO and 17,819 LO CRC cases had KRAS testing with a KRAS mutation frequency of 40% and 41%, respectively. Compared with LO tumors harboring mutated KRAS, EO tumors with KRAS mutations were more frequently found in females (52% vs. 45%, P < 0.001), left-sided (LS) or rectal cancers (62% vs. 48%, P < 0.001), stage III/IV (89% vs. 81%, P < 0.001), and grade III/IV (21% vs. 18%, P = 0.038). Compared to CSS in EO with KRAS mutation, LO with KRAS mutation was associated with worse prognosis—with an overall hazard ratio (HR) of 1.21 (95% CI, 1.15-1.27, P < 0.0001). Results [HR (95% CI)] from Cox analyses on the effects of KRAS mutation on CSS, stratified by sidedness, are shown below. Conclusions: Despite EO CRC carrying worse prognostic factors than LO CRC, it confers better CSS than LO CRC. EO CRC is distinct from LO CRC in clinical and pathological features, in addition to its response to mutant KRAS. Mutated KRAS is an independent prognostic factor in LS colon and rectal cancers among the LO, but not in the EO population. [Table: see text]

Tumor Molecular Testing Guides Anti-PD-1 Therapy and Provides Evidence for Pathogenicity of Mismatch Repair Variants

Lynch syndrome is characterized by germline abnormalities in mismatch repair (MMR) genes, leading to predisposition to multiple cancers [1]. A second hit to the unaffected allele is required for tumorigenesis. MMR proteins repair incorrectly paired nucleotides and prevent generation of insertions and deletions at microsatellites [2]. Aberrancies in these MMR proteins can be a result of germline mutations or somatic alterations. Defective MMR results in microsatellite instability (MSI) and a high mutational burden [3].The clinical implications of MSI are becoming readily apparent, as presence of MSI leads to the generation of neoantigens, stimulating tumor-associated lymphocytes [4], [5]. This has led to the use of programmed cell death protein 1 blockade for MMR-deficient tumors [6]. The U.S. Food and Drug Administration recently approved pembrolizumab for any advanced solid tumor demonstrating MSI and nivolumab for metastatic MSI colorectal cancer. However, the clinical significance of numerous MMR gene variants remains uncertain. The International Society for Gastrointestinal Hereditary Tumors classification system categorizes 2,360 MMR variants, which can be used to gauge pathogenicity [7]. There are many variants of uncertain significance (VUS; or class 3) for which clinicians are unable to provide recommendations. In this study, we employed the combination of germline testing and tumor mutational assessment to help discern the clinical relevance of VUS and guide immunotherapeutic decisions. KEY POINTS: A clinical dilemma arises when genomic testing yields variants of uncertain significance (VUS).Germline VUS were identified in two patients with gastrointestinal malignancies, but only one patient had a second-hit mutation in a mismatch repair gene leading to mismatch repair deficiency that conferred response to immunotherapy.The combination of germline testing along with tumor mutational assessment can help discern the clinical relevance of VUS and can help guide therapeutic decision-making toward individualized patient care.

Hyperactive cyclic motor activity in the distal colon after colonic surgery as defined by high-resolution colonic manometry

BACKGROUND

Recovery after colonic surgery is invariably delayed by disturbed gut motility. It is commonly assumed that colonic motility becomes quiescent after surgery, but this hypothesis has not been evaluated rigorously. This study quantified colonic motility through the early postoperative period using high-resolution colonic manometry.

METHODS

Fibre-optic colonic manometry was performed continuously before, during and after surgery in the left colon and rectum of patients undergoing right hemicolectomy, and in healthy controls. Motor events were characterized by pattern, frequency, direction, velocity, amplitude and distance propagated.

RESULTS

Eight patients undergoing hemicolectomy and nine healthy controls were included in the study. Colonic motility became markedly hyperactive in all operated patients, consistently dominated by cyclic motor patterns. Onset of cyclic motor patterns began to a minor extent before operation, occurring with increasing intensity nearer the time of surgery; the mean(s.d.) active duration was 12(7) per cent over 3 h before operation and 43(17) per cent within 1 h before surgery (P = 0.024); in fasted controls it was 2(4) per cent (P < 0·001). After surgery, cyclic motor patterns increased markedly in extent and intensity, becoming nearly continuous (active duration 94(13) per cent; P < 0·001), with peak frequency 2-4 cycles per min in the sigmoid colon. This postoperative cyclic pattern was substantially more prominent than in non-operative controls, including in the fed state (active duration 27(20) per cent; P < 0·001), and also showed higher antegrade velocity (P < 0·001).

CONCLUSION

Distal gut motility becomes markedly hyperactive with colonic surgery, dominated by cyclic motor patterns. This hyperactivity likely represents a novel pathophysiological aspect of the surgical stress response. Hyperactive motility may contribute to gut dysfunction after surgery, potentially offering a new therapeutic target to enhance recovery.

Identification of perioperative pulmonary aspiration in children using quality assurance and hospital administrative billing data

BACKGROUND

Perioperative aspiration is a rare but potentially devastating complication, occurring in 1-10 per 10 000 anesthetics based on studies of quality assurance databases. Quality assurance reporting is known to underestimate the incidence of adverse outcomes, but few large studies use supplementary data sources. This study aims to identify the incidence of and risk factors for perioperative aspiration in children using quality assurance data supplemented by administrative billing records, and to examine the utility of billing data as a supplementary data source.

METHODS

Aspiration events for children receiving anesthesia at a tertiary care pediatric hospital between 2008 and 2014 were identified using (i) a perioperative quality assurance database and (ii) hospital administrative billing records with International Classification of Diseases, Ninth Revision Clinical Modification coded diagnoses of aspiration. Records were subject to review by pediatric anesthesiologists. Following identification of all aspiration events, the incidence of perioperative aspiration was calculated and risk factors were assessed.

RESULTS

47 272 anesthetic cases were evaluated over 7 years. The quality assurance database identified 20 cases of perioperative aspiration occurring in surgical inpatients, same-day admissions, and outpatients. Using hospital administrative data (which excludes outpatients with shorter than a 24-hour stay), 9 cases of perioperative aspiration were identified of which 6 had not been found through quality assurance data. Overall, International Classification of Diseases, Ninth Revision coding demonstrated a positive predictive value of 94.5% for any aspiration event; however, positive predictive value was <4% for perioperative aspiration. A total incidence of 5.5 perioperative aspirations per 10 000 (95% CI: 3.7-8.0 per 10 000) anesthetics was found.

CONCLUSION

Quality assurance data offer an efficient way to measure the incidence of rare events, but may underestimate perioperative complications. International Classification of Diseases, Ninth Revision codes for aspiration used as a secondary data source were nonspecific for perioperative aspiration, but when combined with record review yielded a 30% increase in identified cases of aspiration over quality assurance data alone. The use of administrative data therefore holds potential for supplementing quality assurance studies of rare complications.

Sidedness, mutations, and survival in stage IV colon cancer: A U.S. population-based study

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Background: Despite recent diagnostic and therapeutic advances in colon cancer (CC), it remains one of the leading causes for cancer-related deaths worldwide. At time of diagnosis, 20% of CC patients (PTS) present with de novo stage IV. In recent years, clinical trials have identified sidedness and several molecular biomarkers (MBM), such as microsatellite instability high (MSI-H), KRAS and BRAF mutations, as prognostic and predictive factors for treatment response in stage IV CC. However, their impact and interactions in the population-based setting remain elusive. Methods: The National Cancer Institute’s 2014 Patterns of Care study included a sample of 1,444 stage IV CC PTS from Surveillance, Epidemiology, and End Results registries, and captured MSI, BRAF and detailed chemotherapy information not available in the public-use dataset. Demographic, tumor, molecular and treatment data were compared using chi-square tests. Cox proportional hazards models were used to compare overall survival (OS) across subgroups of demographic, tumor, MBM and treatment characteristics. Results: Compared to left-sided (L) CC, PTS diagnosed with right-sided (R) CC tend to be older (median age: 65 vs 60, respectively; p < 0.001), more females (54% vs 44%, p = 0.001), African Americans (25% vs 22%, p = 0.001), have poorly or undifferentiated tumors (27% vs 15%, p = 0.001), and harbor MSI-H (14% vs 7%, p = 0.018), KRAS (52% vs 36%, p < 0.001) or BRAF (29% vs 11%, p = 0.001) mutations. FOLFOX, with or without bevacizumab, accounted for > 50% of the first-line regimens. Multivariable Cox proportional hazards models revealed the following poor risk factors: right-sidedness, poorly or undifferentiated tumor, no surgery, no chemotherapy, no cetuximab/panitumumab or no bevacizumab therapy. In separate models for LCC and RCC among those tested for KRAS (n = 689), treatment with bevacizumab was associated with lower odds of death in both models (p < 0.05). Cetuximab/panitumumab were nearly significantly associated with lower odds of death in LCC (p = 0.06) but not RCC (0.35). Conclusions: Right-sidedness is a poor prognostic factor in stage IV CC. Regardless of sidedness, stage IV CC PTS can benefit from surgery, chemotherapy, or bevacizumab.

Microsatellite instability and adjuvant chemotherapy in stage II colon cancer

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Background: Randomized control trials and population-based studies have not demonstrated a definitive benefit for adjuvant chemotherapy in stage II colon cancers. Tumor side and microsatellite instability (MSI) have been proposed as prognostic and predictive factors, but there is little consensus about their utility. Previous studies have been limited by the availability of MSI data. Because microsatellite stability (MSS) is associated with worse prognosis and higher risk of metastases, we hypothesized patients with MSS would have increased benefit from chemotherapy. Methods: Using the National Cancer Database, we preformed a retrospective cohort study of patients with resected stage II colon cancer diagnosed 2006-2013. Patient and disease characteristics were compared with chi-square tests. Survival was evaluated with Cox proportional hazard models. Results: We identified 59,475 patients with stage II colon cancer. 11.4% of patients had known MSI status (n = 6,763) of which 88% had MSS (n = 5,953) and 12% had MSI (n = 810). Patients with MSS were more likely to receive chemotherapy (28.2% vs 19.9%, p < 0.001) and have left-sided tumors (38.8% vs 16.7%, p < 0.001). MSI (adjusted hazard ratio [HR] 0.64, 95% confidence interval [CI] 0.48-0.87; p = 0.003) and receipt of chemotherapy (HR 0.54, 95% CI 0.42-0.69; p < 0.001) were associated with better survival after controlling for multiple characteristics including tumor side. Although left-sided tumors had better survival on univariate analysis (HR 0.91, 95% CI 0.88-0.94; p < 0.001), side was not an independent predictor of survival after controlling for MSI and other characteristics (HR 1.01, 95% CI 0.86-1.20; p = 0.860). Among patients with MSS, chemotherapy remained associated with improved survival (HR 0.54, 95% CI 0.43-0.70; p < 0.001) and this benefit did not vary by tumor side (interaction p = 0.380). There was no interaction between MSI status and chemotherapy (p = 0.139), but we observed less of a survival benefit for chemotherapy in patients with MSI (HR 0.81, 95% CI 0.38-1.75; p = 0.595). Conclusions: Our data suggest a benefit for adjuvant chemotherapy in stage II colon cancer even after adjusting for MSI status. However, tumor side was not prognostic after controlling for MSI status.

Acute Kidney Injury Secondary to Cell Saver in Posterior Spinal Fusion

BACKGROUND

Autologous blood transfusion, commonly referred to as cell saver, is frequently used in spinal fusion to salvage red blood cells because of the risk of significant intraoperative blood loss. This case report describes a case of acute kidney injury (AKI) secondary to cell saver use. Our objective is to increase the knowledge about the process of red blood cell salvage and this exceedingly rare complication.

METHODS

Chart and renal biopsy results for a single case were reviewed and reported in this retrospective study.

RESULTS

A healthy 18-year-old male patient underwent posterior spinal instrumentation and fusion for adolescent idiopathic scoliosis with utilization of intraoperative autologous blood transfusion. The patient subsequently developed hematuria and AKI with a peak creatinine of 13.9 mg/dL. An extensive clinical workup, including autoimmune serology, excluded any identifying causes. A renal biopsy showed pigment-induced acute tubular necrosis.

CONCLUSIONS

This case, to our knowledge, is the first and only case report of AKI secondary to cell saver demonstrated by renal biopsy. The literature has shown both the benefit of cell saver by decreasing the need for allogeneic transfusion and the risk of transient hematuria. However, this case demonstrates the importance of monitoring patients for potential complications.

A personalized, web-based prognostic tool for resectable gastric cancer

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Background: Gastric cancer (GC) mortality remains high, with a 5-year survival of 30 percent. For patients with resectable GC, mortality varies depending on both patient and tumor characteristics. The current study sought to develop a web-based prognostic model to assist patients and health care providers in decision making regarding either surgery-only or adjuvant chemoradiotherapy (CRT). Methods: California SEER data was used and records, including demographic, pathologic, and treatment information, for 2,583 patients diagnosed with stage IB to III GC and treated with either surgery only or adjuvant CRT from 2006 to 2013 were retrieved. Purposeful selection using Cox regression model was used to identify important mortality predictors. Additionally, with simple random sampling, 70% of the data were assigned to the training set and the remaining 30% were assigned to the test set. Furthermore, generalized boosted classification model was trained using the training set and validated using the test set. Area under the curve (AUC) of the receiver operating characteristic (ROC), sensitivity, specificity and accuracy were determined for 5- and 10-year mortality. Results: The median survival was 33 months for patients in the training set, and 32 for the test set. Predictors included in the model were age, ethnicity (Asian/other, Hispanic, non-Hispanic black and non-Hispanic white), T-stage, histology (intestinal, diffuse and other), presence of signet ring (yes/no), proximal location (yes/no), lymph node ratio, and CRT following surgery (yes/no). Validation of the model on the test set showed as follows: AUC, sensitivity, specificity and accuracy of 0.78(95%CI = 0.75,0.82), 0.75, 0.65 and 0.70 for 5-year survival and 0.77(95%CI = 0.74,0.80), 0.79, 0.55 and 0.70 for 10-year survival. Conclusions: The proposed web-based prognostic tool using readily available patient and tumor characteristic provides validated and personalized prognostic information to aide clinicians and patients in GC adjuvant treatment decision process. [Table: see text]

Prognostic value of PD-L1 expression in colorectal cancer

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Background: Growing evidence have shown promise for targeting programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) signaling in several tumors. However, the role of PD-L1 expression in colorectal cancer (CRC) tumor cells and its interaction with other clinicopathologic factors remain elusive. Methods: We constructed a tissue microarray with paraffin-embedded primary colon cancer tissue (n=103; stage I, 22; II: 44; III: 37). Expression levels of biomarkers (PD-L1, EGFR, p53, Ki67, LEF1, VEGF, COX2, MMR – by IHC, and MiR-34a - by in situ hybridization), clinicopathologic variables and clinical outcomes were investigated. H-score evaluation of PD-L1 was performed. Tumors with an H score >55, derived using Cutoff Finder, were considered PD-L1 positive for use in Kaplan-Meier survival analysis with log-rank test and in Cox regression models for recurrence-free survival (RFS) and overall survival (OS). Results: Median follow-up time for the entire cohort was 4.7 years (range 0.1-20.8). Positive PLD1 was identified in 89% of cases. As a group, cases with positive PD-L1 expression had better OS than those with negative expressions (12.2 vs 3.3 years) (p = 0.043), especially in cases with mismatch repair proficiency (MMR-P, 12.1 vs 1.0 years) (p <0.001). Negative PD-L1 expression in cases who had no chemotherapy was associated with worse outcome for OS (p=0.001) and RFS (p=0.008). There was no significant association between PD-L1 expression and gender, age, tumor size, pathologic stage or tumor grade. However, PD-L1 expression was significantly associated with MiR-34a (p<0.001) and p53 overexpression (p=0.008) with a trend toward association in cases with mismatch repair proficiency (MMR-P, p=0.053). Conclusions: Our results suggest that negative PD-L1 expression appears to have negative prognostic value with worse RFS and OS in stage I - III CRC patients, especially those who had not received any chemotherapy. Given a recent study suggesting p53/miR-34a/PD-L1 axis as a novel mechanism of immune evasion, and strong correlation in the PD-L1/p53 and PD-L1/miR-334a expressions in our cohort, further investigation of their interactions is warranted that may lead to identifying their predictive value for immuno/chemotherapy.

Whole-Organism Cellular Pathology: A Systems Approach to Phenomics

Phenotype is defined as the state of an organism resulting from interactions between genes, environment, disease, molecular mechanisms, and chance. The purpose of the emerging field of phenomics is to systematically determine and measure phenotypes across biology for the sake of understanding. Phenotypes can affect more than one cell type and life stage, so ideal phenotyping would include the state of every cell type within the context of both tissue architecture and the whole organism at each life stage. In medicine, high-resolution anatomic assessment of phenotype is obtained from histology. Histology's interpretative power, codified by Virchow as cellular pathology, is derived from its ability to discern diagnostic and characteristic cellular changes in diseased tissues. Cellular pathology is observed in every major human disease and relies on the ability of histology to detect cellular change in any cell type due to unbiased pan-cellular staining, even in optically opaque tissues. Our laboratory has shown that histology is far more sensitive than stereomicroscopy for detecting phenotypes in zebrafish mutants. Those studies have also shown that more complete sampling, greater consistency in sample orientation, and the inclusion of phenotypes extending over longer length scales would provide greater coverage of common phenotypes. We are developing technical approaches to achieve an ideal detection of cellular pathology using an improved form of X-ray microtomography that retains the strengths and addresses the weaknesses of histology as a screening tool. We are using zebrafish as a vertebrate model based on the overlaps between zebrafish and mammalian tissue architecture, and a body size small enough to allow whole-organism, volumetric imaging at cellular resolution. Automation of whole-organism phenotyping would greatly increase the value of phenomics. Potential societal benefits would include reduction in the cost of drug development, a reduction in the incidence of unexpected severe drug and environmental toxicity, and more rapid elucidation of the contributions of genes and the environment to phenotypes, including the validation of candidate disease alleles identified in population and personal genetics.

Changing epidemiology of gastric sarcomas in the United States

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Background: The introduction of imatinib as targeted therapy for the treatment of gastrointestinal stromal tumors (GIST) has supplied a strong impetus for the reclassification of gastric sarcomas (GS). We examined the changes in the incidence and mortality over the last 20 years for GS subtypes using the Surveillance, Epidemiology, and End Results (SEER) database over the last 20 years. Methods: Based on information from SEER, GS cases were identified by primary cancer site and ICD-O-3 codes. SEER*stat was used to make estimates of incidence and cause specific survival. Joinpoint software was used to test for trends. Results: The overall incidence of GS increased of from 1991 and to 2011 from 2.9 (standard error [SE] 0.4) to 6.6 (SE 0.6) cases per million per year. The histologic subtypes of changed over this time interval with the leiomyosarcoma being initially the leading GS subtype with an incidence from 2.3 (SE 0.4) decreasing to 0.1 (SE 0.1). The incidence of gastric GIST increased from 0.1 (SE 0.1) to 6.3 (SE 0.6) representing 95% of all GS cases in 2011. For GS test for trend with Joinpoint model did not detect a discontinuity in the trend (occurring at a rate of 4.7% [p < 0.001]) relative increase per year. Much of the total GS increase in incidence was for localized disease with the incidence rates which increased from 1.2 to 4.5 cases per 10^6/year a relative increase of 6.8% (p < 0.01) per year. During this period the 3-year cause specific mortality improved for localized GS from 9.4% to 0.9%. Improvements were also seen for mortality outcomes for regional and distant disease. Conclusions: Between 1991 and 2011, more than a doubling of incidence of GS was observed with a concurrent rapid change in GIST - most in localized disease and a dramatic improvement in its outcome. It seems unlikely that this is due to changes in the underlying biology of the disease, or to imatinib alone, but may be, in part, due to changes in diagnostic techniques or pathologic evaluation

Prognostic role of microRNA-34a expression in colorectal cancer

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Background: Colorectal Cancer (CRC) is one of the leading causes of death worldwide. MicroRNA-34a (miR-34a), a tumor suppressor gene, is known to be down-regulated in CRC cell lines and recently shown to be a cell-fate determinant in early-stage dividing colon cancer stem cells. However, its prognostic significance is unclear. Methods: MiR-34a detection was performed by in situ hybridization on a CRC tissue microarray (n=127; stage I, 21 patients; II: 42; III: 33; IV: 31). Its expression was graded as negative (no signal), low (expression in 1-19% of cancer cells), moderate (20-49% of cancer cells), and strong (50-100% of cancer cells). The correlations between miR-34a expression and EGFR, osteopontin (OPN), p53, Ki67, LEF1, VEGF, COX2, MMR, stage and grade were evaluated by chi-squared test and Spearman's rank correlation coefficient. Kaplan-Meier survival analysis, log-rank test and Cox regression model were used to assess the association of miR-34a expression with recurrence-free survival (RFS) and disease specific survival (DSS). Results: MiR-34a expression had moderate positive correlation with genes associated with tissue proliferation and invasion, including Ki67 (Spearman's r=0.28, p=0.002), and weak correlation with EGFR (r=0.2, p=0.02) and LEF1 (r=0.18, p=0.039). In the subgroup of patients (n=75; stage II/III) with negative OPN expression (n=25), weak or negative miR-34a expression was associated with worse RFS (HR=4.1; 95%CI=1.1-15.9; p=0.036) and DSS (HR=10.5; 95%CI=1.2-94.5; p=0.036). Conclusions: Our results suggest that down-regulated or absent expression of miR-34a correlates with worse RFS and DSS in stage II - III CRC patients with negative OPN expression. Further investigation of miR34a in prospective randomized studies is warranted to establish its role as a prognostic factor for CRC outcome.

Stromal responses among common carcinomas correlated with clinicopathologic features

PURPOSE

We have previously characterized a tumor stroma expression signature in a subset of breast tumors that correlates with better clinical outcome. The purpose of this study is to determine whether this stromal signature, termed the "DTF fibroblast" (desmoid-type fibromatosis) signature, is specific to breast cancer or is a common stromal response found in different types of cancer.

EXPERIMENTAL DESIGNS

The DTF fibroblast signature was applied to gene expression profiles from five ovarian, five lung, two colon, and three prostate cancer expression microarray datasets. In addition, two different tissue microarrays of 204 ovarian tumors and 140 colon tumors were examined for the expression of previously characterized protein markers of DTF fibroblast signature. The DTF fibroblast stromal response was then correlated with clinicopathologic features.

RESULTS

The DTF fibroblast signature is robustly present in ovarian, lung, and colon carcinomas. Both expression microarray data and immunohistochemistry show that the subset of ovarian tumors with strong DTF fibroblast signature expression has statistically significant, worse survival outcomes. No reproducible survival differences were found in either the lung or the colon cancers. The prostate cancers failed to show a DTF fibroblast signature. Multivariant analysis showed that DTF fibroblast signature was significantly more prognostic than the proliferation status in ovarian carcinomas.

CONCLUSIONS

Our results suggest that the DTF fibroblast signature is a common tumor stroma signature in different types of cancer, including ovarian, lung, and colon carcinomas. Our findings provide further insight into the DTF fibroblast stromal responses across different types of carcinomas and their potential as prognostic and therapeutic targets.

Micro-RNA-21 (miR21) expression in colorectal cancer (CRC) as a predictor for fluoropyrimidine-based adjuvant chemotherapy

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Background: Fluoropyrimidine-based adjuvant chemotherapy is a standard treatment option for patients with high risk II or stage III CRC. It is, however, unclear if a subset of patients will benefit from chemotherapy more than others. MiR21, a small non-coding RNA, has been associated with promotion of tumor cell growth and metastasis. To assess the effect of miR21 on chemotherapy, we analyzed the association of miR21 expression with clinical outcomes and known prognostic factors. Methods: MicroRNA detection was performed by in situ hybridization on a CRC tissue microarray containing specimens from 130 cases (stage I, 21 patients; II: 44; III: 33; IV: 32). MiR21 expression was graded as negative (no staining in all tissue cores), low (0-10% staining), moderate (20-40%) and strong (50-100%), and was analyzed with stage, grade, expression of VEGF, Ki67, LEF1, OPN and MSH2 by immunohistochemistry. Cox proportional hazards regression analysis was performed to assess the association of miR21 expression with 10-year recurrence-free survival in the subgroup of 77 stage II or III patients. Results: In all, miR21 expression had moderate positive correlation with genes associated with tissue proliferation and invasion, including Ki67 (Spearman's r=0.42, p<0.001), VEGF (r=0.32, p<0.001) and OPN (r=0.32, p<0.001), and weak correlation with LEF1 (r=0.22, p=0.012) and MSH 2 (r=0.18, p=0.039). In the subgroup of 36 patients treated with adjuvant therapy, low or negative miR21 expression (≤10%, n=15) was associated with increased recurrence (HR =3.5; p=0.05). In the multivariate Cox regression model including stage, grade and LEF1 expression, the association of low or negative miR21 with cancer recurrence remained significant along with grade and LEF1. Ki67 was excluded from the multivariate model because of significant association with miR21 (r=0.44, p=0.007) in the analyzed group. Conclusions: Our results suggest that low miRNA21 expression is associated with increased risk for recurrence in CRC patients received adjuvant chemotherapy. Further investigation of miR21 in randomized studies is warranted to establish its role as a predictor for CRC in the setting of adjuvant therapy.

Identification of a 14-gene signature that predicts survival in colorectal cancer with liver metastasis

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Background: Colorectal cancer (CRC) is the third leading cause of cancer death in men and women combined in the USA. Colorectal liver metastasis (CLM), the most common metastasis of CRC, accounts for at least two thirds of CRC deaths. The purpose of this study is to identify a gene signature that predicts patient survival in patients with CLM. Methods: We analyzed the gene expression profiles of specimens from 24 CLM patients (M:F = 14:10) who underwent metastatic liver resection and unmatched primary CRC specimens from an independent cohort of 30 patients (M:F = 14:16). The association between gene expression levels and survival outcome was evaluated using Cox proportional hazards regression. Random Forests and risk scores were used to construct a gene expression-based survival classifier. Results: Based on survival classifier of CLM patients, a 14-gene signature was developed. According to leave-one-out cross validation, all 24 CLM patients (median follow-up time of 25 months) were correctly assigned into high-risk or low-risk groups (p=0.001). This 14-gene signature was then validated in an independent cohort of 30 primary CRC patients (median follow-up time of 42.2 months; p= 0.03) and a subset of 11 patients who were diagnosed at presentation or follow-up with liver metastasis (M:F = 5:6; median follow-up time of 27.6 months; p=0.04). Conclusions: We have identified a 14-gene signature that predicts the survival of CLM patients after liver resection, with validation in an independent cohort. Although sample size is small, the significance level achieved with our survival analysis warrants further investigation of this 14-gene signature in a larger sample size.

Comparative profiling of primary colorectal carcinomas and liver metastases identifies LEF1 as a prognostic biomarker

Purpose

We sought to identify genes of clinical significance to predict survival and the risk for colorectal liver metastasis (CLM), the most common site of metastasis from colorectal cancer (CRC).

Patients and Methods

We profiled gene expression in 31 specimens from primary CRC and 32 unmatched specimens of CLM, and performed Significance Analysis of Microarrays (SAM) to identify genes differentially expressed between these two groups. To characterize the clinical relevance of two highly-ranked differentially-expressed genes, we analyzed the expression of secreted phosphoprotein 1 (SPP1 or osteopontin) and lymphoid enhancer factor-1 (LEF1) by immunohistochemistry using a tissue microarray (TMA) representing an independent set of 154 patients with primary CRC.

Results

Supervised analysis using SAM identified 963 genes with significantly higher expression in CLM compared to primary CRC, with a false discovery rate of <0.5%. TMA analysis showed SPP1 and LEF1 protein overexpression in 60% and 44% of CRC cases, respectively. Subsequent occurrence of CLM was significantly correlated with the overexpression of LEF1 (chi-square p = 0.042), but not SPP1 (p = 0.14). Kaplan Meier analysis revealed significantly worse survival in patients with overexpression of LEF1 (p<0.01), but not SPP1 (p = 0.11). Both univariate and multivariate analyses identified stage (p<0.0001) and LEF1 overexpression (p<0.05) as important prognostic markers, but not tumor grade or SPP1.

Conclusion

Among genes differentially expressed between CLM and primary CRC, we demonstrate overexpression of LEF1 in primary CRC to be a prognostic factor for poor survival and increased risk for liver metastasis.

Impact of initial surgical margins and residual cancer upon re-excision on outcome of patients with localized breast cancer

BACKGROUND

A significant proportion of patients undergoing breast conservation therapy require additional operations to obtain clear margins. The aim of this study was to assess the impact of initial margins and residual carcinoma found on second surgery on the outcomes of breast cancer patients.

METHODS

In this retrospective study, Cox proportional-hazard regression analysis was performed to evaluate data from 437 patients with stage I to IIIA breast cancer who underwent initial breast-conserving surgery between 1994 and 2004.

RESULTS

The distant recurrence rate was higher among patients with initial positive margins than among those with initial negative margins (15.5% vs 4.9%; hazard ratio, 3.6; 95% confidence interval 1.5-8.7; P = .003). For patients who had underwent second surgery, the finding of a residual invasive carcinoma was associated with increased risk for distant recurrence (22.8% vs 6.6%; hazard ratio, 3.5; 95% confidence interval, 1.8-7.4; P = .0001).

CONCLUSION

Invasive residual carcinoma found during subsequent surgery after initial compromised margins is an important prognostic marker for distant recurrence.

Demonstrating circulation in vasculogenic mimicry patterns of uveal melanoma by confocal indocyanine green angiography

PURPOSE

Vasculogenic mimicry patterns, formed by highly invasive melanoma cells, connect to endothelial cell-lined blood vessels and contain fluid in vitroand in vivo. This study was designed to determine if fluid leaks into vasculogenic mimicry patterns without circulation, or if fluid circulates in and clears from these patterns.

METHODS

Indocyanine green (ICG) laser scanning confocal angiography (Heidelberg Retinal Angiograph (HRA); Heidelberg Engineering, Heidelberg, Germany) was performed on nine patients with posterior choroidal melanoma in an institutional setting. Blood was drawn before the ICG injection and from the contralateral arm of the ICG injection site and 1 min after the injection. Outcome measures include time to first filling of retinal vessels and vasculogenic mimicry patterns and the time at which no fluorescence could be detected by the HRA instrument. After fluorescence was no longer detected in vessels or patterns, the tubes containing the patient's blood was imaged by the Heidelberg HRA.

RESULTS

Looping vasculogenic mimicry patterns were detected focally in five patients within 30 s after injection and were detectable up to 12 min post-injection. Blood drawn before ICG injection did not autofluoresce but ICG-containing blood pooled in the tube continued to fluoresce at 1-month post-injection.

CONCLUSIONS

Vasculogenic mimicry patterns are not part of the endothelial cell-lined vascular system and fluid enters these patterns through leakage. The rapid infusion of ICG into these patterns after injection and the disappearance of fluorescence detectable by the Heidelberg HRA suggest that fluid circulates in these patterns and does not accumulate as a stagnant pool.

Expression of growth differentiation factor-5 and bone morphogenic protein-7 in intraocular osseous metaplasia

BACKGROUND/AIMS

Intraocular bone is seen in a wide spectrum of ocular disorders. The pathogenetic mechanisms of bone formation in the eye are unclear. Growth differentiation factor-5 (GDF-5), bone morphogenic protein-7 (BMP-7), and transforming growth factor beta-1 (TGF beta1) are multifunctional cytokines that have important roles in bone formation. Immunohistochemistry was used to localise GDF-5, BMP-7, and TGF beta1 in the human eye to determine their role in intraocular bone formation.

METHODS

Paraffin embedded sections from human eyes included fetal eyes (n = 5), normal adult eyes (n = 4), eyes with osseous metaplasia (n = 8), and eyes with focal fibrous metaplasia of the retinal pigment epithelium (RPE) without osseous metaplasia (n = 2). Immunohistochemistry was performed using indirect immunofluorescence with antibodies to GDF-5, BMP-7, and TGF beta1. The staining intensity was evaluated semiquantitatively in the RPE, retina, ciliary epithelium, and cornea; and analysed statistically.

RESULTS

When compared with normal adult eyes, which showed no RPE immunoreactivity, the RPE metaplasia surrounding areas of osseous metaplasia showed mild GDF-5 and moderate BMP-7 (p = 0.004) intracytoplasmic immunoreactivity. In contrast, trace GDF-5 and mild BMP-7 staining was seen in zones of RPE fibrous metaplasia in areas not associated with osseous metaplasia. Mild intracytoplasmic TGF beta1 expression was seen in the RPE metaplasia surrounding the bone when compared with adult eyes. Both fetal and adult eyes showed trace to mild GDF-5 and BMP-7 labelling of the non-pigmented ciliary epithelium which was increased in the eyes with osseous metaplasia. In eyes with osseous metaplasia, a significant decrease in GDF-5 and BMP-7 labelling was noted in fetal keratocytes (p = 0.0159 for both antibodies) when compared to adult eyes. Also, a significant decrease in BMP-7 labelling was seen in keratocytes in eyes with osseous metaplasia (p = 0.0162).

CONCLUSIONS

The increase in GDF-5, BMP-7, and TGF beta1 immunoreactivity in zones of RPE metaplasia in eyes with osseous metaplasia suggests that these proteins have an important role in intraocular ectopic bone formation.

Phase II study of thalidomide in patients with unresectable hepatocellular carcinoma

BACKGROUND

The hypervascular nature of hepatocellular carcinoma (HCC) is well characterized. Recent data have suggested that thalidomide possesses antiangiogenic and immunomodulatory activity. Therefore, the authors initiated a study to assess the efficacy and toxicity of thalidomide in patients with advanced HCC as primary and secondary endpoints, respectively.

METHODS

Inclusion criteria were unresectable HCC with bidimentionally measurable disease, age > or = 18 years, Eastern Cooperative Oncology Group performance status < or = 2, and adequate organ function. Thalidomide was administered at a starting dose of 200 mg per day in a 100-mg-per-week dose escalation regimen, up to the maximum tolerated dose or to 800 mg per day. Toxicity was monitored according to the National Cancer Institute Common Toxicity Criteria.

RESULTS

Twenty-six of 27 patients were eligible and assessable for toxicity and response. A median daily dose of 300 mg was achieved. One patient experienced near-complete recovery of alpha-fetoprotein levels and a partial radiographic response on computed tomography. Two patients had stable disease during the 16-week study period. The median duration of progression-free survival was 42 days. The overall median survival was 123 days. Fatigue and somnolence were the most common side effects, occurring in 81% and 62% of patients, respectively. No Grade 4 hematologic toxicity was observed. Three patients experienced Grade 4 hepatic toxicity (namely, hyperbilirubinemia).

CONCLUSIONS

With gradual dose escalation, thalidomide was tolerated in most patients with advanced HCC. However, treatment with thalidomide alone was associated with only a modest response in the treatment of HCC.

Breast cancer characteristics of Vietnamese women in the Greater San Francisco Bay Area

OBJECTIVES

To examine breast cancer characteristics of women of Vietnamese ancestry living in the San Francisco Bay Area in comparison with those of other racial or ethnic groups in the same area.

DESIGN

Data were obtained from the population-based Greater Bay Area Cancer Registry, part of the Surveillance, Epidemiology, and End Results program. We included breast cancer cases diagnosed from 1988 to 1999 and compared the age at diagnosis, stage and histologic grade at diagnosis, estrogen- and progesterone-receptor status, and surgery types across racial or ethnic groups. We also modeled the effect of patient and clinical characteristics and hospital and physician on the racial or ethnic variations in surgery type.

RESULTS

Vietnamese women were younger at diagnosis than other racial or ethnic subgroups (mean age, 51.0 years), with 49.6% of the diagnoses occurring in patients younger than 50. They were also significantly more likely to have received mastectomy for their in situ and localized tumors (61.1% having mastectomy) than women of other racial or ethnic groups. The increased likelihood of having mastectomy among Vietnamese women was not affected greatly by age, year of diagnosis, tumor stage, histologic grade, or physician, but was partly attributable to the hospital of diagnosis.

CONCLUSIONS

The effects of a lower mean age at diagnosis and the reasons for an unexpectedly higher percentage of mastectomies in this Asian subgroup should be further explored.

HLA-DR, HLA-DQ, and TAP genes in familial Hodgkin disease

The HLA region has long been implicated in sporadic and familial Hodgkin disease (HD), with recent case-control studies suggesting that HLA class II loci predispose to sporadic nodular sclerosis HD (NSHD). To determine whether this predisposition extends to familial HD, HLA class II loci (DRB1, DQA1, DQB1, DRB3, DRB4, and DRB5) and transporter associated with antigen processing (TAP) loci (TAP1, TAP2) were investigated in 100 members of 16 families with at least 2 confirmed cases of HD. With the use of the transmission disequilibrium test, evidence for linkage disequilibrium with familial HD and, in particular, familial NSHD was obtained for the DRB1*1501-DQA1*0102-DQB1*0602 haplotype, the TAP1 allele encoding Ile at residue 333, and the DRB5-0101 allele. These 3 markers were in linkage disequilibrium and may not represent independent susceptibility regions. Use of a family-based approach excludes population stratification as an explanation for these findings.

The development of lymphomas in families with autoimmune lymphoproliferative syndrome with germline Fas mutations and defective lymphocyte apoptosis

Lymphomas were studied in kindreds with autoimmune lymphoproliferative syndrome (ALPS; Canale-Smith syndrome), a disorder of lymphocyte homeostasis usually associated with germline Fas mutations. Fas (CD95/APO-1) is a cell surface receptor that initiates programmed cell death, or apoptosis, of activated lymphocytes. Lymphoma phenotype was determined by immunohistochemistry, frequency of CD3(+)CD4(-)CD8(-) T-cell-receptor alpha/beta cells by flow cytometry, nucleotide sequences of the gene encoding Fas (APT1, TNFRSF6), and the percentage of lymphocytes undergoing apoptosis in vitro. Of 223 members of 39 families, 130 individuals possessed heterozygous germline Fas mutations. Eleven B-cell and T-cell lymphomas of diverse types developed in 10 individuals with mutations in 8 families, up to 48 years after lymphoproliferation was first documented. Their risk of non-Hodgkin and Hodgkin lymphomas, respectively, was 14 and 51 times greater than expected (each P <.001). Investigation of these 10 patients and their relatives with Fas mutations revealed that all had defective lymphocyte apoptosis and most had other features of ALPS. The tumor cells retained the heterozygous Fas mutations found in the peripheral blood and manifested defective Fas-mediated killing. These data implicate a role for Fas-mediated apoptosis in preventing B-cell and T-cell lymphomas. Inherited defects in receptor-mediated lymphocyte apoptosis represent a newly appreciated risk factor for lymphomas.