Immune checkpoint inhibitors for POLE or POLD1 proofreading-deficient metastatic colorectal cancer.

BACKGROUND: POLE and POLD1 proofreading deficiency (POLE/D1pd) define a rare subtype of ultramutated metastatic colorectal cancer (mCRC; over 100 mut/Mb). Disease-specific data about the activity and efficacy of immune checkpoint inhibitors (ICIs) in POLE/D1pd mCRC are lacking and it is unknown whether outcomes may be different from mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) mCRCs treated with ICIs. PATIENTS AND METHODS: In this global study, we collected 27 patients with mCRC harboring POLE/D1 mutations leading to proofreading deficiency and treated with anti-programmed cell death-ligand 1 alone +/- anti-cytotoxic T-lymphocyte antigen-4 agents. We collected clinicopathological and genomic characteristics, response, and survival outcomes after ICIs of POLE/D1pd mCRC and compared them with a cohort of 610 dMMR/MSI-H mCRC patients treated with ICIs. Further genomic analyses were carried out in an independent cohort of 7241 CRCs to define POLE and POLD1pd molecular profiles and mutational signatures. RESULTS: POLE/D1pd was associated with younger age, male sex, fewer RAS/BRAF driver mutations, and predominance of right-sided colon cancers. Patients with POLE/D1pd mCRC showed a significantly higher overall response rate (ORR) compared to dMMR/MSI-H mCRC (89% versus 54%; P = 0.01). After a median follow-up of 24.9 months (interquartile range: 11.3-43.0 months), patients with POLE/D1pd showed a significantly superior progression-free survival (PFS) compared to dMMR/MSI-H mCRC [hazard ratio (HR) = 0.24, 95% confidence interval (CI) 0.08-0.74, P = 0.01] and superior overall survival (OS) (HR = 0.38, 95% CI 0.12-1.18, P = 0.09). In multivariable analyses including the type of DNA repair defect, POLE/D1pd was associated with significantly improved PFS (HR = 0.17, 95% CI 0.04-0.69, P = 0.013) and OS (HR = 0.24, 95% CI 0.06-0.98, P = 0.047). Molecular profiling showed that POLE/D1pd tumors have higher tumor mutational burden (TMB). Responses were observed in both subtypes and were associated with the intensity of POLE/D1pd signature. CONCLUSIONS: Patients with POLE/D1pd mCRC showed more favorable outcomes compared to dMMR/MSI-H mCRC to treatment with ICIs in terms of tumor response and survival.

Different prognostic values of KRAS exon 2 submutations and BRAF V600E mutation in microsatellite stable (MSS) and unstable (MSI) stage III colon cancer: an ACCENT/IDEA pooled analysis of seven trials.

BACKGROUND: The prognostic value of KRAS and BRAFV600E mutations in stage III colon cancer (CC) remains controversial and has never been clearly analyzed in patients with microsatellite instability-high (MSI-H) tumors due to sample size limitations. Data are also lacking for KRAS submutations and prognosis. PATIENTS AND METHODS: We examined clinicopathological variables and prognosis in patients with surgically resected stage III CC who participated in seven clinical trials from the ACCENT/IDEA databases. Associations between KRAS exon 2 and BRAFV600E mutations and time to recurrence (TTR), overall survival (OS), and survival after recurrence (SAR) were assessed using a Cox model. We also analyzed the prognostic value of KRAS exon 2 submutations. RESULTS: Among 8460 patients, 11.4% had MSI-H status. In the MSI-H group, BRAFV600E, KRAS exon 2 mutants, and double-wild-type statuses were detected in 40.6%, 18.1%, and 41.3%, respectively, whereas and in the microsatellite stable (MSS) group, these were detected in 7.7%, 38.6%, and 53.8%, respectively. In the MSS group, 5-year TTR rates of 61.8%, 66.3%, and 72.9% were observed among patients with BRAFV600E, KRAS exon 2 mutants, and those who were DWT, respectively [adjusted hazard ratio (HR) = 1.58 and 1.31, both P < 0.001]. In the MSI-H group, 5-year TTR rates did not differ significantly among the mutated subgroups. Similar results were found for OS. However, survival after relapse was significantly shorter in the KRAS exon 2- and BRAFV600E-mutated patients in both MSS (adjusted HR = 2.06 and 1.15; both P < 0.05) and MSI-H (adjusted HR = 1.99 and 1.81; both P < 0.05) groups. In the MSS group, KRAS exon 2 mutations were associated with TTR, but only p.G12C, p.G12D, and p.G13D were associated with poor outcomes after disease recurrence. CONCLUSIONS: Testing for both KRAS and BRAFV600E mutations in stage III patients should be considered as they can better define individual patient prognosis, and may also enable patient selection for (neo)adjuvant trials dedicated to specific molecular subtypes with poor prognosis.

Changes in the multidisciplinary management of rectal cancer from 2009 to 2015 and associated improvements in short-term outcomes.

AIM: Significant recent changes in management of locally advanced rectal cancer (LARC) include preoperative staging, use of extended neoadjuvant therapies and minimally invasive surgery (MIS). This study was aimed at characterizing these changes and associated short-term outcomes. METHOD: We retrospectively analysed treatment and outcome data from patients with T3/4 or N+ LARC ≤ 15 cm from the anal verge who were evaluated at a comprehensive cancer centre in 2009-2015. RESULTS: In total, 798 patients were identified and grouped into five cohorts based on treatment year: 2009-2010, 2011, 2012, 2013 and 2014-2015. Temporal changes included increased reliance on MRI staging, from 57% in 2009-2010 to 98% in 2014-2015 (P < 0.001); increased use of total neoadjuvant therapy, from 17% to 76% (P < 0.001); and increased use of MIS, from 33% to 70% (P < 0.001). Concurrently, median hospital stay decreased (from 7 to 5 days; P < 0.001), as did the rates of Grade III-V complications (from 13% to 7%; P < 0.05), surgical site infections (from 24% to 8%; P < 0.001), anastomotic leak (from 11% to 3%; P < 0.05) and positive circumferential resection margin (from 9% to 4%; P < 0.05). TNM downstaging increased from 62% to 74% (P = 0.002). CONCLUSION: Shifts toward MRI-based staging, total neoadjuvant therapy and MIS occurred between 2009 and 2015. Over the same period, treatment responses improved, and lengths of stay and the incidence of complications decreased.

Clinical and molecular characterization of patients with cancer of unknown primary in the modern era.

BACKGROUND: On the basis of historical data, patients with cancer of unknown primary (CUP) are generally assumed to have a dismal prognosis with overall survival of less than 1 year. Treatment is typically cytotoxic chemotherapy guided by histologic features and the pattern of metastatic spread. The purpose of this study was to provide a clinical and pathologic description of patients with CUP in the modern era, to define the frequency of clinically actionable molecular alterations in this population, to determine how molecular testing can alter therapeutic decisions, and to investigate novel uses of next-generation sequencing in the evaluation and treatment of patients with CUP. PATIENTS AND METHODS: Under Institutional Review Board approval, we identified all CUP patients evaluated at our institution over a recent 2-year period. We documented demographic information, clinical outcomes, pathologic evaluations, next-generation sequencing of available tumor tissue, use of targeted therapies, and clinical trial enrollment. RESULTS: We identified 333 patients with a diagnosis of CUP evaluated at our institution from 1 January 2014 through 30 June 2016. Of these patients, 150 had targeted next-generation sequencing carried out on available tissue. Median overall survival in this cohort was 13 months. Forty-five of 150 (30%) patients had potentially targetable genomic alterations identified by tumor molecular profiling, and 15 of 150 (10%) received targeted therapies. Dominant mutation signatures were identified in 21 of 150 (14%), largely implicating exogenous mutagen exposures such as ultraviolet radiation and tobacco. CONCLUSIONS: Patients with CUP represent a heterogeneous population, harboring a variety of potentially targetable alterations. Next-generation sequencing may provide an opportunity for CUP patients to benefit from novel personalized therapies.

Predicted vitamin D status and colon cancer recurrence and mortality in CALGB 89803 (Alliance).

BACKGROUND: Observational studies suggest that higher levels of 25-hydroxyvitamin D3 (25(OH)D) are associated with a reduced risk of colorectal cancer and improved survival of colorectal cancer patients. However, the influence of vitamin D status on cancer recurrence and survival of patients with stage III colon cancer is unknown. PATIENTS AND METHODS: We prospectively examined the influence of post-diagnosis predicted plasma 25(OH)D on outcome among 1016 patients with stage III colon cancer who were enrolled in a National Cancer Institute-sponsored adjuvant therapy trial (CALGB 89803). Predicted 25(OH)D scores were computed using validated regression models. We examined the influence of predicted 25(OH)D scores on cancer recurrence and mortality (disease-free survival; DFS) using Cox proportional hazards. RESULTS: Patients in the highest quintile of predicted 25(OH)D score had an adjusted hazard ratio (HR) for colon cancer recurrence or mortality (DFS) of 0.62 (95% confidence interval [CI], 0.44-0.86), compared with those in the lowest quintile (Ptrend = 0.005). Higher predicted 25(OH)D score was also associated with a significant improvement in recurrence-free survival and overall survival (Ptrend = 0.01 and 0.0004, respectively). The benefit associated with higher predicted 25(OH)D score appeared consistent across predictors of cancer outcome and strata of molecular tumor characteristics, including microsatellite instability and KRAS, BRAF, PIK3CA, and TP53 mutation status. CONCLUSION: Higher predicted 25(OH)D levels after a diagnosis of stage III colon cancer may be associated with decreased recurrence and improved survival. Clinical trials assessing the benefit of vitamin D supplementation in the adjuvant setting are warranted. CLINICALTRIALS.GOV IDENTIFIER: NCT00003835.

Survival following early-stage colon cancer: an ACCENT-based comparison of patients versus a matched international general population†.

BACKGROUND: Post-treatment survival experience of early colon cancer (CC) patients is well described in the literature, which states that cure is probable for some patients. However, comparisons of treated patients' survival versus that expected from a matched general population (MGP) are limited. PATIENTS AND METHODS: A total of 32 745 patients from 25 randomized adjuvant trials conducted from 1977 to 2012 in 41 countries were pooled. Observed long-term survival of these patients was compared with expected survival matched on sex, age, country, and year, both overall and by stage (II and III), sex, treatment [surgery, 5-fluorouracil (5-FU), 5-FU + oxaliplatin], age (<70 and 70+), enrollment year (pre/post 2000), and recurrence (yes/no). Comparisons were made at randomization and repeated conditional on survival to 1, 2, 3, and 5 years. CC and MGP equivalence was tested, and observed Kaplan-Meier survival rates compared with expected MGP rates 3 years out from each landmark. Analyses were also repeated in patients without recurrence. RESULTS: Within most cohorts, long-term survival of CC patients remained statistically worse than the MGP, though conditional survival generally improved over time. Among those surviving 5 years, stage II, oxaliplatin-treated, elderly, and recurrence-free patients achieved subsequent 3-year survival rates within 5% of the MGP, with recurrence-free patients achieving equivalence. CONCLUSIONS: Conditional on survival to 5 years, long-term survival of most CC patients on clinical trials remains modestly poorer than an MGP, but achieves MGP levels in some subgroups. These findings emphasize the need for access to quality care and improved treatment and follow-up strategies.

A phase II study of gemcitabine and cisplatin plus sorafenib in patients with advanced biliary adenocarcinomas.

BACKGROUND: This study evaluated the addition of sorafenib to gemcitabine and cisplatin in biliary adenocarcinoma first-line therapy. METHODS: Patients with advanced biliary adenocarcinomas received gemcitabine 1000 mg m(-2) and cisplatin 25 mg m(-2) on a 2 weeks on/1 week off cycle and sorafenib 400 mg twice daily. After the initial 16 patients were enrolled, the chemotherapy doses were amended in view of grade 3 and 4 hand-foot skin reaction and haematologic toxicity. Subsequently, 21 patients received gemcitabine 800 mg m(-2), cisplatin 20 mg m(-2) and sorafenib 400 mg. The primary end point was an improvement in 6-month progression-free survival (PFS6) from historical 57-77% (90% power, type I error of 10%). Pretreatment pERK, evaluated by immunostaining, was correlated with clinical outcome. RESULTS: A total of 39 patients were accrued. The most common grade 3-4 toxicities noted in >10% of patients were fatigue, elevated liver function tests and haematologic toxicities including thromboemboli, hyponatraemia and hypophosphataemia. Six-month progression-free survival was 51% (95% confidence interval (CI) 34-66%). Median PFS and overall survival were 6.5 (95% CI: 3.5-8.3) and 14.4 months (95% CI: 11.6-19.2 months), respectively. No correlation was observed between pERK and outcomes. CONCLUSION: The addition of sorafenib to gemcitabine and cisplatin in biliary adenocarcinomas did not improve efficacy over historical data, and toxicity was increased.

Goblet cell carcinoid neoplasm of the appendix: clinical and CT features.

PURPOSE: To describe the clinical and CT imaging features of goblet cell carcinoid (GCC) neoplasm of the appendix. METHODS AND MATERIALS: A computer search of pathology and radiology records over a 19-year period at our two institutions was performed using the search string "goblet". In the patients with appendiceal GCC neoplasms who had abdominopelvic CT, imaging findings were categorized, blinded to gross and surgical description, as: "Appendicitis", "Prominent appendix without peri-appendiceal infiltration", "Mass" or "Normal appendix". The CT appearance was correlated with an accepted pathological classification of: low grade GCC, signet ring cell adenocarcinoma ex, and poorly differentiated adenocarcinoma ex GCC group. RESULTS: Twenty-seven patients (age range, 28-80 years; mean age, 52 years; 15 female, 12 male) with pathology-proven appendiceal GCC neoplasm had CT scans that were reviewed. Patients presented with acute appendicitis (n=12), abdominal pain not typical for appendicitis (n=14) and incidental finding (n=1). CT imaging showed 9 Appendicitis, 9 Prominent appendices without peri-appendiceal infiltration, 7 Masses and 2 Normal appendices. Appendicitis (8/9) usually correlated with typical low grade GCC on pathology. In contrast, the majority of Masses and Prominent Appendices without peri-appendiceal infiltration were pathologically confirmed to be signet ring cell adenocarcinoma ex GCC. Poorly differentiated adenocarcinoma ex GCC was seen in only a small minority of patients. Hyperattenuation of the appendiceal neoplasm was seen in a majority of cases. CONCLUSIONS: GCC neoplasm of the appendix should be considered in the differential diagnosis in patients with primary appendiceal malignancy. Our cases demonstrated close correlation between our predefined CT pattern and the pathological classification.

Dynamic contrast enhanced-MRI for the detection of pathological complete response to neoadjuvant chemotherapy for locally advanced rectal cancer.

OBJECTIVE: To determine the ability of dynamic contrast enhanced (DCE-MRI) to predict pathological complete response (pCR) after preoperative chemotherapy for rectal cancer. METHODS: In a prospective clinical trial, 23/34 enrolled patients underwent pre- and post-treatment DCE-MRI performed at 1.5T. Gadolinium 0.1 mmol/kg was injected at a rate of 2 mL/s. Using a two-compartmental model of vascular space and extravascular extracellular space, K(trans), k(ep), v(e), AUC90, and AUC180 were calculated. Surgical specimens were the gold standard. Baseline, post-treatment and changes in these quantities were compared with clinico-pathological outcomes. For quantitative variable comparison, Spearman's Rank correlation was used. For categorical variable comparison, the Kruskal-Wallis test was used. P ≤ 0.05 was considered significant. RESULTS: Percentage of histological tumour response ranged from 10 to 100%. Six patients showed pCR. Post chemotherapy K(trans) (mean 0.5 min(-1) vs. 0.2 min(-1), P = 0.04) differed significantly between non-pCR and pCR outcomes, respectively and also correlated with percent tumour response and pathological size. Post-treatment residual abnormal soft tissue noted in some cases of pCR prevented an MR impression of complete response based on morphology alone. CONCLUSION: After neoadjuvant chemotherapy in rectal cancer, MR perfusional characteristics have been identified that can aid in the distinction between incomplete response and pCR. KEY POINTS: Dynamic contrast enhanced (DCE) MRI provides perfusion characteristics of tumours. These objective quantitative measures may be more helpful than subjective imaging alone Some parameters differed markedly between completely responding and incompletely responding rectal cancers. Thus DCE-MRI can potentially offer treatment-altering imaging biomarkers.

XELOX vs FOLFOX-4 as first-line therapy for metastatic colorectal cancer: NO16966 updated results.

BACKGROUND: We report updated overall survival (OS) data from study NO16966, which compared capecitabine plus oxaliplatin (XELOX) vs 5-fluorouracil/folinic acid plus oxaliplatin (FOLFOX4) as first-line therapy in metastatic colorectal cancer. METHODS: NO16966 was a randomised, two-arm, non-inferiority, phase III comparison of XELOX vs FOLFOX4, which was subsequently amended to a 2 × 2 factorial design with further randomisation to bevacizumab or placebo. A planned follow-up exploratory analysis of OS was performed. RESULTS: The intent-to-treat (ITT) population comprised 2034 patients (two-arm portion, n=634; 2 × 2 factorial portion, n=1400). For the whole NO16966 study population, median OS was 19.8 months in the pooled XELOX/XELOX-placebo/XELOX-bevacizumab arms vs 19.5 months in the pooled FOLFOX4/FOLFOX4-placebo/FOLFOX4-bevacizumab arms (hazard ratio 0.95 (97.5% CI 0.85-1.06)). In the pooled XELOX/XELOX-placebo arms, median OS was 19.0 vs 18.9 months in the pooled FOLFOX4/FOLFOX4-placebo arms (hazard ratio 0.95 (97.5% CI 0.83-1.09)). FOLFOX4 was associated with more grade 3/4 neutropenia/granulocytopenia and febrile neutropenia than XELOX, and XELOX with more grade 3 diarrhoea and grade 3 hand-foot syndrome than FOLFOX4. CONCLUSION: Updated survival data from study NO16966 show that XELOX is similar to FOLFOX4, confirming the primary analysis of progression-free survival. XELOX can be considered as a routine first-line treatment option for patients with metastatic colorectal cancer.

Efficacy of capecitabine versus 5-fluorouracil in colorectal and gastric cancers: a meta-analysis of individual data from 6171 patients.

BACKGROUND: To compare the effects of oral capecitabine-containing chemotherapy regimens with i.v. 5-fluorouracil (5-FU)-containing chemotherapy regimens on overall survival in patients with gastrointestinal cancers. METHODS: A meta-analysis, based on individual patient data from six randomised non-inferiority trials, was carried out at the request of regulatory authorities to compare the effects of single-agent capecitabine or capecitabine-containing chemotherapy versus matched 5-FU-based regimens in terms of overall survival in patients with stage III colon, metastatic colorectal or advanced gastric cancer. RESULTS: Data from a total of 6171 patients with stage III colon cancer (n = 1987), metastatic colorectal cancer (n = 3868) or advanced gastric cancer (n = 316) were included. A total of 3097 patients were treated with capecitabine-containing chemotherapy and 3074 patients with 5-FU-containing chemotherapy. The unadjusted hazard ratio for overall survival for capecitabine-containing chemotherapy versus 5-FU-containing chemotherapy was 0.94 (95% confidence interval 0.89-1.00; P = 0.0489). CONCLUSIONS: Oral capecitabine is at least equivalent to i.v. 5-FU in terms of overall survival in patients with gastrointestinal cancers. Capecitabine and 5-FU can be used interchangeably in these patient populations.

Two or three year disease-free survival (DFS) as a primary end-point in stage III adjuvant colon cancer trials with fluoropyrimidines with or without oxaliplatin or irinotecan: data from 12,676 patients from MOSAIC, X-ACT, PETACC-3, C-06, C-07 and C89803.

BACKGROUND: The ACCENT group previously established disease-free survival (DFS) with 2 or 3 years median follow-up to predict 5 year overall survival (5 year OS) in stage II and III colon cancer. ACCENT further proposed (1) a stronger association between DFS and OS in stage III than II, and (2) 6 or 7 years necessary to demonstrate DFS/OS surrogacy in recent trials. The relationship between end-points in trials with oral fluoropyrimidines, oxaliplatin and irinotecan is unknown. METHODS: Associations between the treatment effect hazard ratios (HRs) on 2 and 3 years DFS, and 5 and 6 years OS were examined in 6 phase III trials not included in prior analyses from 1997 to 2002. Individual data for 12,676 patients were analysed; two trials each tested oxaliplatin, irinotecan and oral treatment versus 5-FU/LV. FINDINGS: Overall association between 2/3 year DFS and 5/6 year OS HRs was modest to poor (simple R² measures: 0.58-0.76, model-based R²: 0.17-0.49). In stage III patients, the association increased (model-based R² ≥ 0.79). Observed treatment effects on 2 year DFS accurately 5/6 year OS effects overall and in stage III patients. INTERPRETATION: In recent trials of cytotoxic chemotherapy, 2 or 3 years DFS HRs are highly predictive of 5 and 6 years OS HRs in stage III but not stage II patients. In all patients the DFS/OS association is stronger for 6 year OS, thus at least 6 year follow-up is recommended to assess OS benefit. These data support DFS as the primary end-point for stage III colon cancer trials testing cytotoxic agents.

Surgery with curative-intent in patients treated with first-line chemotherapy plus bevacizumab for metastatic colorectal cancer First BEAT and the randomised phase-III NO16966 trial.

BACKGROUND: Complete resection of metastases can result in cure for selected patients with metastatic colorectal cancer. METHODS: First BEAT evaluated the safety of bevacizumab with first-line chemotherapy in 1914 patients. Prospectively collected data from 225 patients who underwent curative-intent surgery were analysed, including an exploratory comparison of resection rate in patients treated with different regimens. NO16966 compared efficacy of oxaliplatin-based chemotherapy plus bevacizumab or placebo in 1400 patients. A retrospective analysis of resection rate was undertaken. RESULTS: In First BEAT, 225 out of 1914 patients (11.8%) underwent curative-intent surgery at median 64 days (range 42-100) after the last dose of bevacizumab. R0 resection was achieved in 173 out of 225 patients (76.9%). There were no surgery-related deaths and serious post-operative complications were uncommon, with grade 3/4 bleeding and wound-healing events reported in 0.4% and 1.8%, respectively. Resection rates were highest in patients receiving oxaliplatin-based combination chemotherapy (P=0.002), possibly confounded by patient selection. In NO16966, 44 out of 699 patients treated with bevacizumab (6.3%) and 34 out of 701 patients treated with placebo (4.9%) underwent R0 metastasectomy (P=0.24). CONCLUSIONS: The rate of serious post-operative complications in First BEAT was comparable to historical controls without bevacizumab. In NO16966, there were no statistically significant differences in resection rates or overall survival in patients treated with bevacizumab vs placebo.

A phase I study of erlotinib in combination with gemcitabine and radiation in locally advanced, non-operable pancreatic adenocarcinoma.

PURPOSE: To determine the maximum tolerated dose (MTD) of erlotinib when administered concurrently with twice weekly gemcitabine and radiation therapy (RT) for locally advanced pancreatic cancer, assess the safety and toxicity profile of this combination and secondarily evaluate response, time to tumor progression and overall survival. METHODS: Patients with untreated locally advanced pancreas cancer were treated with daily erlotinib in combination with gemcitabine 40 mg/m(2)/30 min twice weekly and RT delivered at 180 cGy/day in 28 fractions over 5.5 weeks for a total of 5040 cGy. Erlotinib was dose escalated in successive cohorts (100 mg, 125 mg). When the MTD was determined, the cohort was expanded to better define toxicity and preliminarily efficacy. All patients were surgically staged. After chemoradiation, patients received maintenance weekly gemcitabine 1000 mg/m(2) on days 1 and 8 of a 21 day cycle and daily erlotinib for four cycles. RESULTS: Three patients were treated at dose level 1 (erlotinib 100 mg) without limiting toxicity. Two of six patients at dose level 2 (erlotinib 125 mg) had dose-limiting toxicities, neutropenia and thrombocytopenia, causing dose delay and elevated liver enzymes. The MTD for erlotinib in combination with twice weekly gemcitabine-based chemoradiation was 100 mg/day. Eleven additional patients were treated at dose level 1. All twenty patients were assessable for toxicity. Seventeen patients were assessable for response. The partial response rate was 35% and 53% had stable disease. The median survival for all patients was 18.7 months. CONCLUSION: In combination with fixed dose gemcitabine at 40 mg/m(2) twice weekly and radiation at 180 cGy/day, the MTD of erlotinib was found to be 100 mg/day. This is a relatively well tolerated, biologically active combination in a poor prognostic cancer.

Neuroendocrine carcinomas of the colon and rectum.

PURPOSE: This study was designed to review experience with neuroendocrine carcinomas of the colon and rectum at a single institution, with emphasis on the pathology and clinical characteristics of this uncommon malignancy. METHODS: A study group of patients was identified from a prospective colorectal service database. Pathology was reviewed and neuroendocrine tumors were classified by a single pathologist. Medical records were retrospectively reviewed. RESULTS: From March 1975 to September 1998, 38 patients with neuroendocrine carcinomas were identified from the colorectal service database comprising 6495 patients (0.6 percent). These neuroendocrine carcinomas did not include carcinoid tumors. Average patient age was 57 years (range, 29-86 years). There were 17 males (44.7 percent) and 21 females (55.3 percent). Tumors were located as follows: 17 colon, 14 rectum, 6 anal canal, and 1 appendix. The diagnosis of neuroendocrine carcinoma was suggested preoperatively from tissue biopsy in 59.3 percent (16/27) of patients evaluable. Pathology was reviewed and tumors were categorized as small cell carcinoma (n = 22) or large cell neuroendocrine carcinoma (n = 16). Most tumors (20/25 evaluable, 80 percent) stained positive by means of immunohistochemistry for neuroendocrine markers, including chromogranin (18/19), synaptophysin (10/15), and/or neuron-specific enolase (14/15). Metastatic disease was detected at the time of diagnosis in 69.4 percent of the patients (25/36). Tumors were advanced at the time of diagnosis, with American Joint Committee on Cancer (AJCC) Stage I (n = 6), Stage III (n = 7), and Stage IV (n = 25) tumors. As a group, these tumors had a poor prognosis, with a median survival of 10.4 months. One-year, two-year, and three-year survival was 46 percent, 26 percent, and 13 percent, respectively. There was no significant difference in survival based on pathologic subtypes. Median follow-up time was 9.4 months (range, 0.6-263.7 months). CONCLUSIONS: Neuroendocrine carcinomas of the colon and rectum are uncommon, comprising less than 1 percent of colon and rectal cancers. Pathologically, these tumors are poorly differentiated carcinomas with distinctive cytoarchitectural features and are often immunoreactive for markers of neuroendocrine differentiation. The prognosis for high-grade neuroendocrine carcinomas is poor, as most patients have metastatic disease at the time of diagnosis.

Phase I study of weekly oxaliplatin plus irinotecan in previously treated patients with metastatic colorectal cancer.

BACKGROUND: In vitro synergy between Oxal (oxaliplatin) and CPT-11 (irinotecan) has been reported. Oxaliplatin exerts its antineoplastic activity through the formation of platinum-DNA adducts. Resistance to oxaliplatin is through repair of these adducts, which is inhibited by irinotecan. PATIENTS AND METHODS: Oxaliplatin and irinotecan were administered weekly for 4 weeks followed by a 2-week rest period. The dose of oxaliplatin was escalated first, starting at 30 mg/m(2). Once a dose of 60 mg/m(2) was attained, the weekly dose of irinotecan was escalated, from 40 mg/m(2) to 85 mg/m(2). A total of 49 previously treated patients with metastatic colorectal cancer were entered in order to establish the maximum tolerated dose. Pharmacokinetics of oxaliplatin and irinotecan were analyzed. RESULTS: Forty-nine patients were evaluable for toxicity. The recommended phase II doses for this combination are oxaliplatin 60 mg/m(2) and irinotecan 50 mg/m(2), weekly x 4 q 6 weeks. Diarrhea was the most common dose-limiting toxicity. No pharmacological interactions were noted between oxaliplatin and irinotecan. Twelve of the 47 evaluable patients (26%) achieved a partial response. CONCLUSION: Weekly combination of oxaliplatin and irinotecan appears to be a well tolerated and active regimen in patients previously treated for metastatic colorectal cancer. Further investigations of this regimen are warranted.

A phase II trial of farnesyl protein transferase inhibitor SCH 66336, given by twice-daily oral administration, in patients with metastatic colorectal cancer refractory to 5-fluorouracil and irinotecan.

BACKGROUND: ras genes encode Ras proteins that are important for signal transduction in cancer cells. Farnesyl protein transferase (FPTase) is an enzyme that is responsible for a critical post-translational modification of Ras. PATIENTS AND METHODS: We report the results of a phase II trial of SCH 66336, an FPTase inhibitor, in patients with metastatic colorectal cancer. This is the first reported experience of an FPTase inhibitor in this disease. All patients were considered refractory to first- and second-line therapy. A total of 21 evaluable patients were treated with a starting dose of 200 mg b.i.d. given continuously. RESULTS: The major side-effects were fatigue (grade 1 in 42%, grade 2 in 42% and grade 3 in 14%), diarrhea (grade 1 in 23% and grade 3 in 42%) and nausea (grade 2 in 16%). Elevations in serum creatinine (grade 2 or 3) were observed in 19% of patients and appeared to be related to dehydration induced by diarrhea. Significant hematological toxicity was not observed (only grade 1 thrombocytopenia in 19% and grade 2 or 3 anemia in 28%). Pharmacological studies revealed adequate mean pre-dose plasma concentrations in this group of patients on day 15 of therapy. No objective responses were observed, although stable disease was seen in three patients for several months. Administration of SCH 66336 was accompanied by gastrointestinal toxicity. CONCLUSIONS: Future development of this compound cannot be recommended as monotherapy in this disease.

Safe and cost effective use of alteplase for the clearance of occluded central venous access devices.

PURPOSE: To determine whether cryopreserved solutions of the thrombolytic agent alteplase could be used as a safe, effective, and economically reasonable alternative to urokinase in patients presenting with occluded central venous access devices (CVADs). MATERIALS AND METHODS: Alteplase has been reported as an efficacious alternative to urokinase for treatment of occluded CVADs. However, the practicality of using alteplase as the thrombolytic of choice for this indication remained conjectural. To make this approach economically feasible, alteplase was diluted to 1 mg/mL and 2.5-mL aliquots were stored at -20 degrees C until use. A need to confirm that the cryopreserving and thawing of the reconstituted solution did not compromise the safety and efficacy reported from prior trials was recognized. A quality assessment initiative was undertaken to concurrently monitor the safety and efficacy of this approach. Patients presenting with occluded CVADs received a sufficient volume of the thawed alteplase solution to fill the occluded catheter(s). Data, including efficacy, adverse reactions, dwell time, and catheter type, were collected over a 5-month period. RESULTS: One hundred twenty-one patients accounting for 168 attempted clearances were assessable for safety and efficacy. One hundred thirty-six (81%) of the 168 catheter clearance attempts resulted in successful catheter clearance (95% confidence interval, 74% to 86%). No adverse events were reported. CONCLUSION: Cryopreserved 1-mg/mL aliquots of alteplase are safe and effective in the clearance of occluded CVADs when stored at -20 degrees C for 30 days. The ability to cryopreserve alteplase aliquots makes it an economically reasonable alternative to urokinase in the setting of CVAD occlusion.

Phase I study of topoisomerase I inhibitor exatecan mesylate (DX-8951f) given as weekly 24-hour infusions three of every four weeks.

Exatecan mesylate (DX-8951f) is a topoisomerase I inhibitor that has increased solubility and antitumor activity compared with other topoisomerase I inhibitors. The purpose of this study was to establish a safe dose of DX-8951f given as a weekly 24-h infusion 3 of every 4 weeks. DX-8951f was administered as a 24-h continuous infusion in escalating doses. Twenty-seven patients were treated with 81 courses of the drug. Dose-limiting toxicities included neutropenia, thrombocytopenia, and inability to administer all three doses in the first cycle. In minimally pretreated patients, a dose of 0.8 mg/m(2) was tolerable. In patients who were heavily pretreated, a slightly lower dose, 0.53 mg/m(2), was tolerated without any severe toxicities. Nonhematological toxicities were mild and consisted of mild diarrhea, asthenia, mild nausea, and constipation. Pharmacokinetic parameters could be well described with a one-compartment model in most patients, although the application of the one-compartment model probably resulted in an underestimated elimination half-life. In conclusion, the recommended Phase II dose for DX-8951f administered as a weekly 24-h infusion on a 3-of-4 week schedule is 0.8 mg/m(2) in minimally pretreated patients and 0.53 mg/m(2) in patients who are heavily pretreated.