P. Paty

Assessing the predictive value of clinical complete response to neoadjuvant therapy for rectal cancer: an analysis of 488 patients

BACKGROUND Patients with transmural or node-positive rectal cancer benefit from the addition of chemoradiation to surgical resection. Administration of the chemoradiation (combined modality therapy) preoperatively has gained popularity in recent years. Some patients undergo apparent complete tumor regression after preoperative combined modality therapy, and controversy exists about the proper management of these patients. Some investigators have proposed that such patients should simply be observed and not undergo resection. STUDY DESIGN The purpose of this study was to determine the significance of clinical complete response to preoperative combined modality therapy. Specifically, we have attempted to determine the frequency with which a clinical complete response (based on the absence of detectable tumor on preoperative digital rectal examination and proctoscopy) correlates with a pathologic complete response (based on the absence of cancer cells in the resected specimen). A retrospective review of the clinical and pathologic characteristics of 488 patients from the Memorial Sloan-Kettering prospective colorectal database who received preoperative chemoradiation followed by resection for primary rectal cancer was performed. The indications for preoperative therapy included clinical or ultrasound T3 or T4 tumors or node-positive disease. RESULTS The clinical complete response rate to preoperative therapy was 19%. All patients underwent resection subsequent to preoperative therapy regardless of response. The pathologic complete response rate among all patients was 10%. The pathologic complete response rate among clinical complete responders was 25%. Clinical complete response was a significant predictive factor for pathologic complete response, but the majority (75%) of clinical complete responders had persistent foci of tumor that were not detectable on preoperative examination or proctoscopy. CONCLUSIONS Clinical complete response to preoperative therapy as determined by preoperative digital rectal examination and proctoscopy or EUA is not an accurate predictor of pathologic complete response. A significant percentage of clinical complete responders have persistent deep tumors or nodal involvement. We do not recommend making treatment decisions based solely on the absence of clinically palpable or visible tumor after chemoradiation. Our data suggest that all acceptable-risk patients with a diagnosis of primary rectal cancer should undergo resection, regardless of their response to preoperative therapy.

Outcome of Primary Tumor in Patients With Synchronous Stage IV Colorectal Cancer Receiving Combination Chemotherapy Without Surgery As Initial Treatment

CRA4030 The full, final text of this abstract will be available in Part II of the 2009 ASCO Annual Meeting Proceedings, distributed onsite at the Meeting on May 30, 2009, and as a supplement to the June 20, 2009, issue of the Journal of Clinical Oncology. [Table: see text].PURPOSE The purpose of this study was to describe the frequency of interventions necessary to palliate the intact primary tumor in patients who present with synchronous, stage IV colorectal cancer (CRC) and who receive up-front modern combination chemotherapy without prophylactic surgery. PATIENTS AND METHODS By using a prospective institutional database, we identified 233 consecutive patients from 2000 through 2006 with synchronous metastatic CRC and an unresected primary tumor who received oxaliplatin- or irinotecan-based, triple-drug chemotherapy (infusional fluorouracil, leucovorin, and oxaliplatin; bolus fluorouracil, leucovorin, and irinotecan; or fluorouracil, leucovorin, and irinotecan) with or without bevacizumab as their initial treatment. The incidence of subsequent use of surgery, radiotherapy, and/or endoluminal stenting to manage primary tumor complications was recorded. RESULTS Of 233 patients, 217 (93%) never required surgical palliation of their primary tumor. Sixteen patients (7%) required emergent surgery for primary tumor obstruction or perforation, 10 patients (4%) required nonoperative intervention (ie, stent or radiotherapy), and 213 (89%) never required any direct symptomatic management for their intact primary tumor. Of those 213 patients, 47 patients (20%) ultimately underwent elective colon resection at the time of metastasectomy, and eight patients (3%) underwent this resection during laparotomy for hepatic artery infusion pump placement. Use of bevacizumab, location of the primary tumor in the rectum, and metastatic disease burden were not associated with increased intervention rate. CONCLUSION Most patients with synchronous, stage IV CRC who receive up-front modern combination chemotherapy never require palliative surgery for their intact primary tumor. These data support the use of chemotherapy, without routine prophylactic resection, as the appropriate standard practice for patients with neither obstructed nor hemorrhaging primary colorectal tumors in the setting of metastatic disease.

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 highgrade neuroendocrine carcinomas is poor, as most patients have metastatic disease at the time of diagnosis.

Phase I Study of Hepatic Arterial Infusion of Floxuridine and Dexamethasone With Systemic Irinotecan for Unresectable Hepatic Metastases From Colorectal Cancer

PURPOSE To determine the maximum-tolerated dose (MTD) and dose-limiting toxicities of concurrent systemic irinotecan and hepatic arterial infusion (HAI) of floxuridine (FUDR) and dexamethasone in patients with unresectable hepatic metastases from colorectal cancer, to determine the safety of this combination in patients who have undergone cryosurgery, and to evaluate the pharmacokinetic effects of HAI FUDR on the metabolism of irinotecan. PATIENTS AND METHODS Forty-six previously treated patients with unresectable liver metastases and no known extrahepatic disease were treated concurrently with intravenous irinotecan weekly for 3 weeks and with HAI of FUDR and dexamethasone for 14 days (both were recycled in 28 days). Parallel cohorts of patients treated with or without cryosurgery were entered at escalating dose levels. RESULTS The MTD for patients who did not undergo cryosurgery was 100 mg/m2 of irinotecan weekly for 3 weeks every 4 weeks with concurrent HAI FUDR (0.16 mg/kg/d x pump volume/flow rate) plus dexamethasone for 14 days of a 28-day cycle. The dose-limiting toxicities were diarrhea and neutropenia. The response rate (complete and partial) among all patients who did not undergo cryosurgery was 74%. All patients in the cryosurgery group responded, and seven of the eight cryosurgery patients developed normal positron emission tomography scans after chemotherapy. HAI FUDR had no effect on the metabolism of irinotecan. CONCLUSION Combination therapy with HAI FUDR and dexamethasone plus systemic irinotecan may be safely administered to patients with unresectable hepatic metastases from colorectal cancer. The MTD has been reached for patients with unresectable disease, and we continue to investigate the MTD for patients who have undergone cryosurgery. Although the main objective of this study was to evaluate the toxicity of the combined regimen, a high response rate (74%) was observed.

Expression of L1-CAM and ADAM10 in human colon cancer cells induces metastasis.

L1-CAM, a neuronal cell adhesion receptor, is also expressed in a variety of cancer cells. Recent studies identified L1-CAM as a target gene of beta-catenin-T-cell factor (TCF) signaling expressed at the invasive front of human colon cancer tissue. We found that L1-CAM expression in colon cancer cells lacking L1-CAM confers metastatic capacity, and mice injected in their spleen with such cells form liver metastases. We identified ADAM10, a metalloproteinase that cleaves the L1-CAM extracellular domain, as a novel target gene of beta-catenin-TCF signaling. ADAM10 overexpression in colon cancer cells displaying endogenous L1-CAM enhanced L1-CAM cleavage and induced liver metastasis, and ADAM10 also enhanced metastasis in colon cancer cells stably transfected with L1-CAM. DNA microarray analysis of genes induced by L1-CAM in colon cancer cells identified a cluster of genes also elevated in a large set of human colon carcinoma tissue samples. Expression of these genes in normal colon epithelium was low. These results indicate that there is a gene program induced by L1-CAM in colon cancer cells that is also present in colorectal cancer tissue and suggest that L1-CAM can serve as target for colon cancer therapy.

T3N0 rectal cancer: results following sharp mesorectal excision and no adjuvant therapy☆

Adjuvant chemoradiation therapy following resection of T3N0 rectal cancer is recommended in order to reduce the incidence of local recurrence and improve survival. However, recent experience with rectal cancer resection utilizing sharp dissection and total mesorectal excision has resulted in a reduction in local recurrence rates to as low as 5% without adjuvant treatment. The purpose of this study was to determine if rectal cancer resection utilizing sharp mesorectal excision alone is adequate treatment for local control of T3N0 rectal cancer. Between July 1986 and December 1993, 95 patients with T3N0M0 rectal cancer underwent resection with sharp mesorectal excision and did not receive any adjuvant therapy. Various prognostic factors were analyzed for their association with local recurrence and survival. Seventy-nine patients had a low anterior resection, 10 of whom had a coloanal anastomosis, and 16 had an abdominoperineal resection. The median follow-up was 53.3 months. Six patients had local recurrence, 12 had distant recurrence, and three had local and distant recurrences. The overall local recurrence rate was 9% crude and 12% 5-year actuarial. The overall crude recurrence rate was 22%. The 5-year disease-specific survival rate was 86.6% with an overall survival of 75%. Postoperative complications occurred in 18 patients (19%). Five patients (6%) had a documented anastomotic leak. Perioperative mortality was 3%. No technical factors, including type of resection (low anterior vs. abdominoperineal), location of tumor, or extent of resection margin, were significant for determining local recurrence. The only histopathologic marker significant for determining local recurrence was lymphatic invasion (P <0.04). Sharp mesorectal excision with low anterior resection or abdominoperineal resection for T3N0M0 rectal cancer results in a local recurrence rate of less than 10% without the use of adjuvant therapy. Therefore, in select patients with T3N0M0 rectal cancer, the standard use of adjuvant therapy for local control may not be justified.

Signet-ring cell carcinoma of the colon and rectum: A matched control study

PURPOSE: There is little information comparing signet-ring cell carcinoma to common non-signet-ring cell colon and rectal cancers. The aim of this study was to better define the clinicopathologic differences between these two distinct entities. METHODS: Using a prospective database of 5,350 surgical patients with rectal cancers operated on at Memorial Sloan-Kettering Cancer Center between 1986 and 1997, 46 patients with signet-ring cell carcinoma were identified. Signet-ring cell carcinoma lesions were those in which signet-ring cells constituted more then 50 percent of the tumor. Six patients who presented with recurrent disease were excluded from the study. Control patients were matched for age, gender, TNM stage, primary site, procedure, and adjuvant therapy. Age, primary site of the tumor, stage at presentation, and survival times of patients with signet-ring cell carcinoma were also compared with 3,371 patients with primary non-signet-ring cell rectal cancers. Survival was calculated using Kaplan-Meier survival estimates. RESULTS: Mean age of the signet-ring cell carcinoma group was 59±12 years and median age was 61 (range, 20–91) years. Male-to-female ratio was 1.1:1. Lymphatic and peritoneal spread was more common among the signet-ring cell carcinoma group. Approximately one-third of signetring cell carcinoma patients presented with metastatic disease. Mean survival time of the signet-ring cell carcinoma group was 45.4 months (95 percent confidence interval, 26.9–63.8) compared with 78.5 months (95 percent confidence interval, 62.0–94.9) for the control patients group;P=0.02 by the log-rank test. The cumulative survival curve of patients with signet-ring cell carcinoma resembles that of patients with poorly differentiated rectal cancers. CONCLUSIONS: Patients with signet-ring cell carcinoma of the colon and rectum have a worse prognosis compared with matched controls with the same stage of disease.

Favorable short-term and long-term outcome after elective radical rectal cancer resection in patients 75 years of age or older

PURPOSE: Because the elderly population in Western countries is rapidly increasing, as is their life expectancy, studies aimed at determining the impact of major surgery for primary rectal cancer in this group are warranted. The purpose of this study was to compare perioperative morbidity and mortality and long-term disease-specific and overall survival in primary rectal cancer patients, older and younger than 75 years of age, subject to major pelvic surgery. METHODS: From September 1986 to December 1996, the Prospective Colorectal Service Database identified 1,120 consecutive patients who underwent major pelvic surgery for primary rectal cancer. Of these, 157 (15 percent) were 75 years of age or older and comprise the elderly group. From the remaining 963 patients younger than 75 years of age, a representative random sample of 174 was selected and constitutes the younger group. Data were obtained from computerized databases and confirmed via chart review and telephone interviews. RESULTS: Perioperative complications were observed in 53 (34 percent) elderly and 63 (36 percent;P=not significant) younger patients. Perioperative deaths occurred in two (1.3 percent) elderly and one (0.6 percent;P=not significant) younger patient. The median follow-up time was 48 months. Although the overall survival was lower in the elderly group (P=0.02; the 5-year overall survival rates were 51 and 66 percent), the disease-specific survival rate was similar in the two groups (P=0.75; the 5-year disease-specific survival rates were 69 and 71 percent). CONCLUSION: In select individuals 75 years of age or older, major pelvic surgery for primary rectal cancer can be done with perioperative morbidity and mortality rates comparable to those obtained in younger individuals, while achieving excellent disease-specific and overall long-term survival.

Functional and quality-of-life outcomes in patients with rectal cancer after combined modality therapy, Intraoperative radiation therapy, and Sphincter preservation

PURPOSE: Locally advanced primary and recurrent rectal cancers treated with external beam radiation therapy, intraoperative radiation therapy, and chemotherapy represent a complex group of patients in the setting of extensive pelvic surgery and sphincter preservation. We sought to define functional outcome and quality of life in this subset of patients. METHODS: We retrospectively reviewed our experience with locally advanced primary and recurrent rectal cancer patients who underwent intraoperative radiation therapy with either low anterior resection (n=12) or coloanal anastomosis (n=6) between 1991 and 1998. Current functional outcome and quality of life were evaluated by a detailed questionnaire. RESULTS: Median time from operation to assessment was 24 (range, 6–93) months. Using a standardized Sphincter Function Scale, incorporating the number of bowel movements per day and degree of incontinence, patients were graded as poor, fair, good, or excellent function. Of all patients, 56 percent reported unfavorable (poor or fair) function. Of the subset of patients with coloanal anastomosis or very low low anterior resection, 88 percent had unfavorable function as compared with 30 percent with standard low anterior resection. (P=0.02; Fishers exact probability test). A quality-of-life satisfaction score based on social, professional, and recreational restrictions demonstrated 56 percent of patients to be dissatisfied with their bowel function. CONCLUSIONS: The majority of patients with advanced rectal cancers who require external beam radiation therapy, extensive pelvic surgery, and intraoperative radiation therapy report unfavorable functional and quality-of-life outcomes after sphincter preservation. In this setting patients being considered for coloanal anastomosis or very low anterior resection may be better served by permanent diversion.

Young Age Influences Treatment but not Outcome of Colon Cancer

BackgroundEarly age at onset is often considered a poor prognostic factor for colon cancer. The aim of this study was to determine the association between age, clinicopathologic features, adjuvant therapy, and outcomes following colon cancer resection.MethodsA prospective database of 1327 surgical stage I–III colon cancer patients operated on from 1990–2001 was evaluated, and patients grouped by age.ResultsSixty-eight patients (5%) were diagnosed at age ≤40 years (younger) compared with 1259 patients diagnosed at age >40 (older). Younger patients were more likely to have left-sided tumors (66% vs 51%, P = .02), but no more likely to present with symptomatic lesions, more advanced tumors, or have worse pathologic features. Younger patients were noted to have more nodes retrieved in their surgical specimens than older patients (median 18 vs 14, P = .001), although the numbers of total colectomies were similar in both groups. Younger patients were also more likely to receive adjuvant chemotherapy, and this was most pronounced in the stage II cohort: 39% vs 14%, P = .003. With a median follow-up of 55 months, 5-year disease-specific survival (DSS) was similar in both study groups: 86% vs 87%, but 5-year overall survival (OS) was significantly higher in the younger patient cohort (84% vs 73%, P = .001).ConclusionYounger patients undergoing complete resection of stage I–III colon cancer had DSS similar to older patients. However, younger patients had more nodes retrieved from their specimens and were more likely to receive adjuvant therapy, especially for node-negative disease. These factors may have contributed to their overall favorable outcome.