An American Society of Clinical Oncology (ASCO) provisional clinical opinion (PCO), offers timely clinical direction to ASCO's oncologists following publication or presentation of potentially ...practice-changing data from major studies. This PCO addresses the utility of KRAS gene mutation testing in patients with metastatic colorectal carcinoma to predict response to anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibody (MoAb) therapy with cetuximab or panitumumab (see Note).
Recent results from phase II and III clinical trials demonstrate that patients with metastatic colorectal cancer benefit from therapy with monoclonal antibodies directed against the EGFR, when used either as monotherapy or combined with chemotherapy. Retrospective subset analyses of the data from these trials strongly suggest that patients who have KRAS mutations detected in codon 12 or 13 do not benefit from this therapy.
Five randomized controlled trials of cetuximab or panitumumab have evaluated outcomes for patients with metastatic colorectal carcinoma in relation to KRAS mutational status as no mutation detected (wild type) or abnormal (mutated). Another five single-arm studies have retrospectively evaluated tumor response according to KRAS status.
Based on systematic reviews of the relevant literature, all patients with metastatic colorectal carcinoma who are candidates for anti-EGFR antibody therapy should have their tumor tested for KRAS mutations in a CLIA-accredited laboratory. If KRAS mutation in codon 12 or 13 is detected, then patients with metastatic colorectal carcinoma should not receive anti-EGFR antibody therapy as part of their treatment.
ASCO's provisional clinical opinions (PCOs) reflect expert consensus based on clinical evidence and literature available at the time they are written, and are intended to assist physicians in clinical decision-making and identify questions and settings for further research. Due to the rapid flow of scientific information in oncology, new evidence may have emerged since the time a PCO was submitted for publication. PCOs are not continually updated and may not reflect the most recent evidence. PCOs cannot account for individual variation among patients, and cannot be considered inclusive of all proper methods of care or exclusive of other treatments. It is the responsibility of the treating physician or other health care provider, relying on independent experience and knowledge of the patient, to determine the best course of treatment for the patient. Accordingly, adherence to any PCO is voluntary, with the ultimate determination regarding its application to be made by the physician in light of each patient's individual circumstances. ASCO PCOs describe the use of procedures and therapies in clinical practice and cannot be assumed to apply to the use of these interventions in the context of clinical trials. ASCO assumes no responsibility for any injury or damage to persons or property arising out of or related to any use of ASCO's PCOs, or for any errors or omissions.
Three agents with differing mechanisms of action are available for treatment of advanced colorectal cancer: fluorouracil, irinotecan, and oxaliplatin. In this study, we compared the activity and ...toxicity of three different two-drug combinations in patients with metastatic colorectal cancer who had not been treated previously for advanced disease.
Patients were concurrently randomly assigned to receive irinotecan and bolus fluorouracil plus leucovorin (IFL, control combination), oxaliplatin and infused fluorouracil plus leucovorin (FOLFOX), or irinotecan and oxaliplatin (IROX). The primary end point was time to progression, with secondary end points of response rate, survival time, and toxicity.
A total of 795 patients were randomly assigned between May 1999 and April 2001. A median time to progression of 8.7 months, response rate of 45%, and median survival time of 19.5 months were observed for FOLFOX. These results were significantly superior to those observed for IFL for all end points (6.9 months, 31%, and 15.0 months, respectively) or for IROX (6.5 months, 35%, and 17.4 months, respectively) for time to progression and response. The FOLFOX regimen had significantly lower rates of severe nausea, vomiting, diarrhea, febrile neutropenia, and dehydration. Sensory neuropathy and neutropenia were more common with the regimens containing oxaliplatin.
The FOLFOX regimen of oxaliplatin and infused fluorouracil plus leucovorin was active and comparatively safe. It should be considered as a standard therapy for patients with advanced colorectal cancer.
With three available chemotherapy drugs for advanced colorectal cancer (CRC), response rate (RR) and survival outcomes have improved with associated morbidity, accentuating the need for tools to ...select optimal individualized treatment. Pharmacogenetics identifies the likelihood of adverse events or response based on variants in genes involved in drug transport, metabolism, and cellular targets.
Germline DNA was extracted from 520 patients on the North American Gastrointestinal Intergroup N9741 study. Three study arms were evaluated: IFL (fluorouracil FU + irinotecan IRN), FOLFOX (FU + oxaliplatin), and IROX (IRN + oxaliplatin). Information on adverse events, response, and disease-free survival was available. Thirty-four variants in 15 candidate genes for analysis based on previous associations with adverse events or outcome were assessed. Genotyping was performed using pyrosequencing.
All variants were polymorphic. The homozygous UGT1A1*28 allele observed in 9% of patients was associated with risk of grade 4 neutropenia in patients on IROX (55% v 15%; P = .002). Deletion in GSTM1 was associated with grade 4 neutropenia after FOLFOX (28% v 16%; P = .02). Patients with a homozygous variant genotype for GSTP1 were more likely to discontinue FOLFOX because of neurotoxicity (24% v 10%; P = .01). The presence of a CYP3A5 variant was significantly associated with RR on IFL (29% v 60%; P = .0074). Most previously published genotype-toxicity or -efficacy relationships were not validated in this study.
This study provides a platform to evaluate pharmacogenetic predictors of response or severe adverse events in advanced CRC. Pharmacogenetic studies can be conducted in multicenter trials, and our findings demonstrate that with continued research, clinical application is practical.
In this report, we update survival (OS) and time-to-progression (TTP) data for the Intergroup trial N9741 after a median 5 years of follow-up by using risk-stratified and prognostic factor analyses ...to determine if treatment outcomes differ in specific patient subgroups.
A total of 1,691 patients were randomly assigned to one of seven fluorouracil-, oxaliplatin-, and irinotecan-containing regimens. OS and TTP were calculated by treatment arm and baseline risk group (on the basis of WBC, performance status, number of sites of disease, and alkaline phosphatase). Multivariate prognostic factor analysis was used to assess clinical factors for their relationships to OS, TTP, response, and toxicity by using Cox and logistic regression models.
The observed 5-year survival with infusional fluorouracil, leucovorin, and oxaliplatin (FOLFOX) of 9.8% was better than with irinotecan plus bolus fluorouracil and leucovorin (IFL; 3.7%; P = .04) or with bolus irinotecan/oxaliplatin (IROX; 5.1%; P = .128). OS and TTP were significantly longer for FOLFOX (20.2 months and 8.9 months, respectively) than for IFL (14.6 months and 6.1 months, respectively; P < .001 for both) or for IROX (17.3 months and 6.7 months, respectively; P < .001 for both). OS differed by risk group: 20.7 months for low risk, 17.4 months for intermediate risk, and 9.4 months for high risk (P < .001). FOLFOX treatment was superior in all risk groups and was the most powerful prognostic factor for OS, TTP, response rate, and toxicity.
The 9.8% 5-year OS in patients with metastatic colorectal cancer who were treated with first-line FOLFOX sets a new benchmark. Neither baseline risk group nor any prognostic factor examined was predictive of treatment-specific outcome. However, treatment efficacy and patient longevity varied as a function of risk group.
Temsirolimus (CCI-779) is a small-molecule inhibitor of the mammalian target of rapamycin (mTOR) and represents a rational therapeutic target against glioblastoma multiforme (GBM).
Recurrent GBM ...patients with < or = 1 chemotherapy regimen for progressive disease were eligible. Temsirolimus was administered in a 250-mg intravenous dose weekly.
Sixty-five patients were treated. The incidence of grade 3 or higher nonhematologic toxicity was 51%, and consisted mostly of hypercholesterolemia (11%), hypertriglyceridemia (8%), and hyperglycemia (8%). Grade 3 hematologic toxicity was observed in 11% of patients. Temsirolimus peak concentration (Cmax), and sirolimus Cmax and area under the concentration-time curve were decreased in patients receiving p450 enzyme-inducing anticonvulsants (EIACs) by 73%, 47%, and 50%, respectively, but were still within the therapeutic range of preclinical models. Twenty patients (36%) had evidence of improvement in neuroimaging, consisting of decrease in T2 signal abnormality +/- decrease in T1 gadolinium enhancement, on stable or reduced steroid doses. Progression-free survival at 6 months was 7.8% and median overall survival was 4.4 months. Median time to progression (TTP) for all patients was 2.3 months and was significantly longer for responders (5.4 months) versus nonresponders (1.9 months). Development of grade 2 or higher hyperlipidemia in the first two treatment cycles was associated with a higher percentage of radiographic response (71% v 31%; P = .04). Significant correlation was observed between radiographic improvement and high levels of phosphorylated p70s6 kinase in baseline tumor samples (P = .04).
Temsirolimus is well tolerated in recurrent GBM patients. Despite the effect of EIACs on temsirolimus metabolism, therapeutic levels were achieved. Radiographic improvement was observed in 36% of temsirolimus-treated patients, and was associated with significantly longer TTP. High levels of phosphorylated p70s6 kinase in baseline tumor samples appear to predict a patient population more likely to derive benefit from treatment. These findings should be validated in other studies of mTOR inhibitors.
Mantle cell lymphoma (MCL) is characterized by a t(11;14) resulting in overexpression of cyclin D1 messenger RNA. This study tested whether temsirolimus (previously known as CCI-779), an inhibitor of ...the mammalian target of rapamycin kinase that regulates cyclin D1 translation, could produce tumor responses in patients with MCL.
Patients with relapsed or refractory MCL were eligible to receive temsirolimus 250 mg intravenously every week as a single agent. Patients with a tumor response after six cycles were eligible to continue drug for a total of 12 cycles or two cycles after complete remission, and were then observed without maintenance.
Thirty-five patients were enrolled and were assessable for toxicity; one patient had MCL by histology but was cyclin D1 negative and was ineligible for efficacy. The median age was 70 years (range, 38 to 89 years), 91% were stage 4, and 69% had two or more extranodal sites. Patients had received a median of three prior therapies (range, one to 11), and 54% were refractory to the last treatment. The overall response rate was 38% (13 of 34 patients; 90% CI, 24% to 54%) with one complete response (3%) and 12 partial responses (35%). The median time-to-progression in all patients was 6.5 months (95% CI, 2.9 to 8.3 months), and the duration of response for the 13 responders was 6.9 months (95% CI, 5.2 to 12.4 months). Hematologic toxicities were the most common, with 71% (25 of 35 patients) having grade 3 and 11% (four of 35 patients) having grade 4 toxicities observed. Thrombocytopenia was the most frequent cause of dose reductions but was of short duration, typically resolving within 1 week.
Single-agent temsirolimus has substantial antitumor activity in relapsed MCL. This study demonstrates that agents that selectively target cellular pathways dysregulated in MCL cells can produce therapeutic benefit. Further studies of this agent in MCL and other lymphoid malignancies are warranted.
Epidermal growth factor receptor (EGFR) amplification in glioblastoma multiforme (GBM) is a common occurrence and is associated with treatment resistance. Erlotinib, a selective EGFR inhibitor, was ...combined with temozolomide (TMZ) and radiotherapy (RT) in a phase I/II trial.
Adults not taking enzyme-inducing anticonvulsants after resection or biopsy of GBM were treated with erlotinib (150 mg daily) until progression. Erlotinib was delivered alone for 1 week, then concurrently with TMZ (75 mg mg/m(2) daily) and RT (60 Gy), and finally, concurrently with up to six cycles of adjuvant TMZ (200 mg/m(2) daily for 5 days every 28 days). The primary end point was survival at 1 year.
Ninety-seven eligible patients were accrued with a median follow-up time of 22.2 months. By definition, the primary end point was successfully met with a median survival time of 15.3 months. However, there was no sign of benefit in overall survival when comparing N0177 with the RT/TMZ arm of the European Organisation for Research and Treatment of Cancer/National Cancer Institute of Canada trial 26981/22981 (recursive partitioning analysis RPA class III, 19 v 21 months; RPA class IV, 16 v 16 months; RPA class V, 8 v 10 months, respectively). Presence of diarrhea, rash, and EGFRvIII, p53, phosphatase and tensin homolog (PTEN), combination EGFR and PTEN, and EGFR amplification status were not predictive (P > .05) of survival.
Although the primary end point was successfully met using nitrosourea-based (pre-TMZ) chemotherapy era historic controls, there was no sign of benefit compared with TMZ era controls. Analyses of molecular subsets did not reveal cohorts of patients sensitive to erlotinib. TMZ chemotherapy combined with RT resulted in improved outcomes compared with historical controls who received nitrosourea-based chemotherapies.
We conducted a cooperative group phase II study to assess antitumor activity and toxicity of sorafenib in patients with metastatic breast cancer (MBC) who had received prior treatment for their ...disease.
Patients were eligible if they had measurable disease and had previously received an anthracycline and/or a taxane in the neoadjuvant, adjuvant, or metastatic setting. The primary end point of the study was tumor response per Response Evaluation Criteria in Solid Tumors (RECIST). The study was designed in two stages. Sorafenib was administered as 400 mg twice daily on days 1 through 28 of each 4-week cycle.
Twenty-three patients were enrolled with a median age of 54 years (range, 37 to 70 years). Twenty-two (96%) had prior anthracycline treatment and 16 (70%) had prior taxane treatment. Patients received sorafenib for a median of two cycles (range, one to 15 cycles) with a median follow-up of 2.4 years (range, 2.2 to 2.6 years). There were no grade 4 toxicities and few grade 3 toxicities. Among the 20 patients eligible for efficacy analysis, no patients experienced a partial response or complete response per RECIST criteria. Thus, the trial stopped at the end of the first stage per study design. Two patients (10%; 90% CI, 1.8% to 28.3%) achieved stable disease lasting longer than 6 months.
Sorafenib as a single agent, although well tolerated, did not exhibit activity when measured by tumor shrinkage in patients with MBC who had received prior treatment. Further research should focus on combinations with standard therapy and end points more sensitive to effects of targeted agents, such as disease stabilization.
Previously, we reported results of Intergroup N9741, which compared standard bolus fluorouracil (FU), leucovorin, plus irinotecan (IFL) with infused FU, leucovorin, plus oxaliplatin (FOLFOX4) and ...irinotecan plus oxaliplatin in patients with untreated metastatic colorectal cancer. High rates of grade > or = 3 toxicity on IFL (resulting in some deaths) led us to reduce the starting doses of both irinotecan and FU by 20% (rIFL). This article compares rIFL with FOLFOX4.
The primary comparison was time to progression, with secondary end points of response rate (RR), overall survival, and toxicity.
Three hundred five patients were randomly assigned. The North Central Cancer Treatment Group Data Safety Monitoring Committee interrupted enrollment at a planned interim analysis when outcomes crossed predetermined stopping boundaries. The results were significantly superior for FOLFOX4 compared with rIFL for time to progression (9.7 v 5.5 months, respectively; P < .0001), RR (48% v 32%, respectively; P = .006), and overall survival (19.0 v 16.3 months, respectively; P = .026). Toxicity profiles were not significantly different between regimens for nausea, vomiting, diarrhea, febrile neutropenia, dehydration, or 60-day all-cause mortality. Sensory neuropathy and neutropenia were significantly more common with FOLFOX4. Approximately 75% of patients in both arms received second-line therapy; 58% of rIFL patients received oxaliplatin-based second-line therapy, and 55% of FOLFOX4 patients received irinotecan-based regimens as second-line therapy.
FOLFOX4 led to superior RR, time to progression, and overall survival compared with rIFL. The survival benefit for FOLFOX4 observed in the earlier stage of the study was preserved with equal use of either irinotecan or oxaliplatin as second-line therapy.
Three agents with differing mechanisms of action are available for treatment of advanced colorectal cancer: fluorouracil, irinotecan, and oxaliplatin. In this study, we compared the activity and ...toxicity of three different two-drug combinations in patients with metastatic colorectal cancer who had not been treated previously for advanced disease.
Patients were concurrently randomly assigned to receive irinotecan and bolus fluorouracil plus leucovorin (IFL, control combination), oxaliplatin and infused fluorouracil plus leucovorin (FOLFOX), or irinotecan and oxaliplatin (IROX). The primary end point was time to progression, with secondary end points of response rate, survival time, and toxicity.
A total of 795 patients were randomly assigned between May 1999 and April 2001. A median time to progression of 8.7 months, response rate of 45%, and median survival time of 19.5 months were observed for FOLFOX. These results were significantly superior to those observed for IFL for all end points (6.9 months, 31%, and 15.0 months, respectively) or for IROX (6.5 months, 35%, and 17.4 months, respectively) for time to progression and response. The FOLFOX regimen had significantly lower rates of severe nausea, vomiting, diarrhea, febrile neutropenia, and dehydration. Sensory neuropathy and neutropenia were more common with the regimens containing oxaliplatin.
The FOLFOX regimen of oxaliplatin and infused fluorouracil plus leucovorin was active and comparatively safe. It should be considered as a standard therapy for patients with advanced colorectal cancer.
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