Prolonged Pemetrexed Infusion Plus Gemcitabine in Refractory Metastatic Colorectal Cancer: Preclinical Rationale and Phase II Study Results.

LESSONS LEARNED: Difficulties in translating in vitro results into clinical practice are inevitable.Further efforts to verify the efficacy of alternative schedules of pemetrexed in solid tumors are encouraged. BACKGROUND: We investigated the cytotoxic activity of pemetrexed in combination with several drugs (gemcitabine, carboplatin, vinorelbine, and mitomycin C) using different exposure schedules in three colon cancer cell lines. The best results were obtained with the following schedule: a prolonged pemetrexed exposure followed by a 48-hour wash-out and then gemcitabine. This combination was then advanced to a phase II clinical trial. METHODS: Patients with metastatic colorectal cancer in progression after standard treatment were included in the study. Adequate bone marrow reserve, normal hepatic and renal function, and an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2 were required. Treatment consisted of an 8-hour intravenous infusion of pemetrexed 150 mg/m2 on day 1 and a 30-minute intravenous infusion of gemcitabine 1,000 mg/m2 on day 3 of each cycle, repeated every 14 days. RESULTS: Fourteen patients were enrolled onto the study (first step). No objective responses were seen, and evidence of stable disease was observed in only one of the 12 evaluable patients. The most important grade 3-4 side effects were hematological toxicity (neutropenia 64.2%, thrombocytopenia 71.4%, anemia 28.7%), fatigue (50.0%), and stomatitis (21.5%). Median overall survival and time to progression were 5.8 months (95% confidence interval [CI]: 3.9-7.1) and 2.1 months (95% CI: 1.7-2.8), respectively. CONCLUSION: The experimental pemetrexed-gemcitabine combination proved to be inactive and moderately toxic.

Predictive role of multiple gene alterations in response to cetuximab in metastatic colorectal cancer: a single center study.

BACKGROUND: KRAS mutations negatively affect outcome after treatment with cetuximab in metastatic colorectal cancer (mCRC) patients. As only 20% of KRAS wild type (WT) patients respond to cetuximab it is possible that other mutations, constitutively activating the EGFR pathway, are present in the non-responding KRAS WT patients. We retrospectively analyzed objective tumor response rate, (ORR) progression-free (PFS) and overall survival (OS) with respect to the mutational status of KRAS, BRAF, PIK3CA and PTEN expression in mCRC patients treated with a cetuximab-based regimen. METHODS: 67 mCRC patients were enrolled onto the study. DNA was extracted from paraffin-embedded sections derived from primary or metastatic lesions. Exon 2 of KRAS and exon 15 of BRAF were analyzed by direct sequencing, PIK3CA was evaluated by pyrosequencing and PTEN expression by immunohistochemistry. RESULTS: BRAF and PIK3CA mutations were independently associated with worse PFS (p = 0.006 and p = 0.028, respectively) and OS (p = 0.008 and p = 0.029, respectively). No differences in clinical outcome were found between patients who were positive or negative for PTEN expression. Conversely, patients negative for KRAS, BRAF and PIK3CA mutations were characterized by significantly better ORR, PFS and OS than patients with at least one of these mutations. CONCLUSIONS: BRAF and PIK3CA mutations would seem to be independent predictors of anti-EGFR therapy effectiveness and could be taken into consideration during treatment decision making.

GEMOX plus tomotherapy for unresectable locally advanced pancreatic cancer.

BACKGROUND/AIMS: The aim of this prospective phase II study was to evaluate the effect of neoadjuvant GEMOX plus helical tomotherapy on the resectability of locally advanced pancreatic cancer. METHODOLOGY: Between November 2004 and July 2008, 33 enrolled patients received gemcitabine (GEM) 1000 mg/m2 on day 1, and oxaliplatin (OX) 100 mg/m2 on day 2, every two weeks for 3-4 cycles. This was followed by radiotherapy (25 Gy, 5 fractions), 15 days after completion of GEMOX. Patients then received a further 3-4 cycles of GEMOX, underwent restaging and were evaluated for surgery. Potentially resectable patients were submitted to surgery, while unresectable responders received further GEMOX and radiotherapy. RESULTS: Toxicity to GEMOX was similar to that reported elsewhere and radiotherapy was also well tolerated. After treatment, one patient achieved a complete response, 14 had a partial response, 11 showed a stable disease, 6 progressed, and one was not evaluable. Eight patients (24%) underwent surgical laparotomy (7 radical pancreatic resections and one explorative laparotomy). CONCLUSIONS: Our study shows the feasibility and potential efficacy of the GEMOX plus helical tomotherapy regimen in unresectable locally advanced pancreatic cancer.

Free DNA and carcinoembryonic antigen serum levels: an important combination for diagnosis of colorectal cancer.

PURPOSE: The identification of new molecular markers for the early detection of colorectal cancer has become an important objective. We compared the sensitivity and specificity of free circulating DNA with that of the more conventional carcinoembryonic antigen (CEA) and evaluated the two markers in combination. EXPERIMENTAL DESIGN: The study was carried out on 75 healthy donors and 75 colorectal cancer patients. Free DNA was determined in serum with quantitative PCR analysis. The diagnostic accuracy of each assay was calculated using receiver operating characteristic (ROC) curves. The diagnostic relevance of the two-marker combination was analyzed by the logistic regression model. RESULTS: Median free DNA concentration was approximately 5-fold higher in patients than in healthy donors (P < 0.001). The area under the ROC curve was 0.86, and when 12.5 ng/mL was used as cutoff, 81.3% sensitivity and 73.3% specificity were observed for the overall series. As CEA and free DNA provided independent diagnostic information, they were also considered in combination. ROC curve analysis of the combined CEA and free DNA algorithms showed a higher diagnostic capacity (area under the ROC curve, 0.92) than that of markers considered singly, with 84% sensitivity and 88% specificity. CONCLUSIONS: Free circulating DNA, especially when used in combination with CEA, represents a potentially useful tool for the diagnosis of early-stage colorectal cancer.

HER-2 expression and cell proliferation: prognostic markers in patients with node-negative breast cancer.

PURPOSE: We analyzed the clinical relevance of HER-2 expression, widely investigated in breast cancer but with contradictory results, in the largest case series of node-negative breast cancer patients investigated to date. PATIENTS AND METHODS: The pure prognostic value of HER-2 expression was investigated in 529 patients treated with locoregional therapy alone until early relapse. Proliferative activity was evaluated as [3H]thymidine labeling index and HER-2 expression by immunohistochemistry. All biologic determinations were conducted within the context of an intra- and interlaboratory National Quality Control Program. RESULTS: HER-2 expression was not related to relapse-free survival in the overall series but was a significant discriminant of prognosis in the subgroup of patients with rapidly proliferating tumors. Six-year rate of relapse was 40% for patients with highly (> or =30%) positive tumors and 26% for those with weakly HER-2-expressing tumors (P =.039). CONCLUSION: HER-2 expression in association with proliferative activity identifies a subgroup of node-negative breast cancer patients with the worst prognosis, who are candidates for specific intensive adjuvant therapy.

Hemangioblastoma of the gastrointestinal tract: a first case.

We present the first documented case of hemangioblastoma located in the left colon. A 75-year-old woman undergoing adjuvant chemotherapy for breast cancer experienced rectal bleeding. Colonoscopy revealed a roundish mass covered with normal mucosa in the sigmoid colon. Endoscopic ultrasound showed an isoechoic lesion originating from the third layer of the intestinal wall; underlying layers were normal. Endoscopic ultrasound features were not suggestive of either cancer or malignant stromal tumor. Left hemicolectomy was subsequently performed due to repeated episodes of lower gastrointestinal bleeding. Grossly, a circumscribed submucosal yellowish nodule (13 mm) was observed, which was not attached to any peripheral nerve. Histologically, the lesion was composed of large, atypical cells traversed by a network of blood vessels. Immunohistochemically, the cells showed positivity for inhibin and NSE and weak positivity for S-100. A diagnosis of hemangioblastoma was made. This case highlights that hemangioblastoma of the gastrointestinal tract can also occur.

Genomic alterations in rectal tumors and response to neoadjuvant chemoradiotherapy: an exploratory study.

BACKGROUND: Neoadjuvant chemoradiotherapy is the treatment of choice in advanced rectal cancer, even though there are many patients who will not benefit from it. There are still no effective methods for predicting which patients will respond or not. The present study aimed to define the genomic profile of rectal tumors and to identify alterations that are predictive of response in order to optimize therapeutic strategies. METHODS: Forty-eight candidates for neoadjuvant chemoradiotherapy were recruited and their pretherapy biopsies analyzed by array Comparative Genomic Hybridization (aCGH). Pathologic response was evaluated by tumor regression grade. RESULTS: Both Hidden Markov Model and Smoothing approaches identified similar alterations, with a prevalence of DNA gains. Non responsive patients had a different alteration profile from responsive ones, with a higher number of genome changes mainly located on 2q21, 3q29, 7p22-21, 7q21, 7q36, 8q23-24, 10p14-13, 13q12, 13q31-34, 16p13, 17p13-12 and 18q23 chromosomal regions. CONCLUSIONS: This exploratory study suggests that an in depth characterization of chromosomal alterations by aCGH would provide useful predictive information on response to neoadjuvant chemoradiotherapy and could help to optimize therapy in rectal cancer patients.The data discussed in this study are available on the NCBI Gene Expression Omnibus [GEO: GSE25885].

Primary tumor response to preoperative chemoradiation with or without oxaliplatin in locally advanced rectal cancer: pathologic results of the STAR-01 randomized phase III trial.

PURPOSE: To investigate oxaliplatin combined with fluorouracil-based chemoradiotherapy as preoperative treatment for locally advanced rectal cancer. PATIENTS AND METHODS: Seven hundred forty-seven patients with resectable, locally advanced (cT3-4 and/or cN1-2) adenocarcinoma of the mid-low rectum were randomly assigned to receive pelvic radiation (50.4 Gy in 28 daily fractions) and concomitant infused fluorouracil (225 mg/m(2)/d) either alone (arm A, n = 379) or combined with oxaliplatin (60 mg/m(2) weekly × 6; arm B, n = 368). Overall survival is the primary end point. A protocol-planned analysis of response to preoperative treatment is reported here. RESULTS: Grade 3 to 4 adverse events during preoperative treatment were more frequent with oxaliplatin plus fluorouracil and radiation than with radiation and fluorouracil alone (24% v 8% of treated patients; P < .001). In arm B, 83% of the patients treated with oxaliplatin had five or more weekly administrations. Ninety-one percent, compared with 97% in the control arm, received ≥ 45 Gy (P < .001). Ninety-six percent versus 95% of patients underwent surgery with similar rates of abdominoperineal resections (20% v 18%, arm A v arm B). The rate of pathologic complete responses was 16% in both arms (odds ratio = 0.98; 95% CI, 0.66 to 1.44; P = .904). Twenty-six percent versus 29% of patients had pathologically positive lymph nodes (arm A v arm B; P = .447), 46% versus 44% had tumor infiltration beyond the muscularis propria (P = .701), and 7% versus 4% had positive circumferential resection margins (P = .239). Intra-abdominal metastases were found at surgery in 2.9% versus 0.5% of patients (arm A v arm B; P = .014). CONCLUSION: Adding oxaliplatin to fluorouracil-based preoperative chemoradiotherapy significantly increases toxicity without affecting primary tumor response. Longer follow-up is needed to assess the impact on efficacy end points.