Medical Management of Colorectal Carcinomas

Potential regional differences for the tolerability profiles of fluoropyrimidines

PURPOSE

We conducted a retrospective analysis of safety data from randomized, single-agent fluoropyrimidine clinical trials (bolus fluorouracil/leucovorin [FU/LV] and capecitabine) to test the hypothesis that there are regional differences in fluoropyrimidine tolerability.

METHODS

Treatment-related safety data from three phase III clinical studies were analyzed by multivariate analysis: two comparing capecitabine with bolus FU/LV in metastatic colorectal cancer (MCRC) and one comparing capecitabine plus oxaliplatin (XELOX) with bolus FU/LV as adjuvant treatment for colon cancer. The United States (US) was compared with non-US countries (all three studies) and with the rest of the world and East Asia (adjuvant study).

RESULTS

In the MCRC studies (n = 1,189), more grade 3/4 adverse events (AEs; relative risk [RR], 1.77), dose reductions (RR, 1.72), and discontinuations (RR, 1.83) were reported in US versus non-US patients. Likewise, in the adjuvant colon cancer study (n = 1,864), more grade 3/4 AEs (RR, 1.47) and discontinuations (RR, 2.09) were reported in US versus non-US patients. After further dividing non-US patients into those in East Asia and the rest of the world, differential RRs for related grade 3/4 AEs, grade 4 AEs, and serious AEs were again observed, with East Asian patients having the lowest and US patients the highest RR.

CONCLUSION

Regional differences exist in the tolerability profiles of fluoropyrimidines. More treatment-related toxicity was reported in the US compared with the rest of the world for bolus FU/LV and capecitabine in first-line MCRC and adjuvant colon cancer. In the adjuvant setting, a range of fluoropyrimidine tolerability was observed, with East Asian patients having the lowest, and US patients the highest, RR.

Results of a Phase II Open-Label Study of Capecitabine in Combination with Irinotecan as First-Line Treatment for Metastatic Colorectal Cancer

BACKGROUND

Between July 2001 and September 2002, 49 eligible patients were enrolled in an open-label phase II study to assess the efficacy and safety of first-line treatment with capecitabine/irinotecan in metastatic colorectal cancer.

PATIENTS AND METHODS

Patients received capecitabine (1000 mg/m2 twice daily) on days 1-14 and irinotecan (240 mg/m2) on day 1 of a 21-day cycle. Patients enrolled had a median age of 64.5 years, and 6% of patients had an Eastern Cooperative Oncology Group performance status of 2. Fifty-seven percent of patients were male.

RESULTS

Forty-two patients were evaluable for response. There was 1 complete response (2%), 18 partial responses (43%), 20 cases of stable disease (48%), and 3 cases of disease progression (7%), for an overall response rate of 45% (95% CI, 30%-60%). The median duration of response was 5.7 months (range, 2.5-II.3 months). Median survival was 13.4 months (range, 1.2-28.8 months) and median progression-free survival was 6.2 months (range, 1.2-17.5 months). At 1 year, the estimated survival rate was 54% and the estimated progression-free survival rate was II%. The median number of cycles received was 6 (range, 1-18 cycles), and most patients (80%) required a dose modification because of diarrhea, nausea, and/or neutropenia. Grade 1/2 hand-foot syndrome occurred in 8 patients (16%). Grade 3/4 toxicities experienced by > or = 5% of patients included diarrhea (20%), neutropenia (12%), dehydration (10%), nausea (10%), anemia (6%), fatigue (6%), pain (6%), and vomiting (6%).

CONCLUSIONS

First-line capecitabine/ irinotecan is an active combination for the treatment of metastatic colorectal cancer and feasible for use in the community-based setting. Despite significant toxicity with the regimen, the treatment was manageable with dose reduction or delay and should be investigated in phase III trials.

Major colorectal cancer resection should not be denied to the elderly

AIMS

Adjuvant therapy after surgery for colorectal cancer is often denied to the elderly for various reasons. This study was to determine morbidity and mortality risk after surgery in the elderly and whether this is affected by adjuvant therapy.

METHODS

Data were collected prospectively and entered on a database for all patients undergoing resection of colorectal cancer between January 1994 and July 2000. A total of 304 patients were included, 65 aged 80 years and over.

RESULTS

There were 84 deaths, 21 (30%) in the over 80s, and 63 (26%) in the under 80s (P=0.51). The 'in-hospital' mortality was 10.1% in the over 80s and 3.8% in the under 80s (P=0.056). In the over 80s the colon was more affected than the rectum (P=0.002). The over 80s were less likely to be offered adjuvant therapy, 7.2% vs 42.1% (P<0.001). The 5 year survival (all-cause mortality) in the over 80s was 58.5% and 47.6% in the under 80s (P=0.25). Cox's regression analysis of all patients identified the following factors to be independently related to overall survival: age>80 years, post-operative leak, increasing Dukes stage and distant recurrence of disease.

CONCLUSION

This study has demonstrated that surgery should not be denied to elderly patients with colorectal cancer as despite a higher post-operative morbidity and mortality rate and with the absence of adjuvant therapy, favourable long-term outcome can be achieved by resectional surgery alone.