Efficacy and safety of irinotecan-based chemotherapy in poor risk patients suffering from metastatic colorectal cancer

Abstract

14581 Background: Irinotecan (CPT11) combination chemotherapy has provided a significant advancement in the management of patients with metastatic colorectal cancer (MCRC). However, there was some data indicating that poor risk cases might not benefit from longer survival with CPT11-based chemotherapy, mainly due to higher regimen toxicity. Purpose: To evaluate the hypothesis, whether CPT-11- based chemotherapy can produce similar TTP and OS in a group of poor risk MCRC patients in comparison to standard risk MCRC cases. Patients and Methods: Out of 170 CRC patients treated in our departments between 2002 - 2006, 36 poor risk MCRC patients (poor risk group was defined as 2 or more criteria being fulfilled, i.e. PS >1, and/or elevated serum LDH, and/or >1 metastatic site, and/or prior adjuvant chemotherapy), were chosen for this analysis and compared retrospectively with our standard risk MCRC cases. The poor risk arm consisted of 9 females and 27 males, in age between 40–76 [median 63,5]. All the patients were treated with CPT11-based chemotherapy, according to either AIO or de Gramont regimen. Results: In the analyzed poor risk group the confirmed RR (CR+PR) after six months of the treatment was 25,0% what was much lower than in standard risk group (RR = 40%), however did not reach the statistical significance; additional 52,8% of patients achieved SD; 8 patients (22,2%) progressed during therapy. The median TTP was 9 months and the median OS was 15 months, what were not statistically different from the standard risk group; 2-year survival obtained 27,8% of patients. No grade (G) 4 toxicity was observed. The most common adverse events (AE) were diarrhea [25% - 9 pts] and neutropenia [11.1% - 4 pts], but G3 AE were noted only in 2 and 1 person respectively. Conclusions: This analysis showed, that CPT11-based chemotherapy is an effective and safe treatment option even for poor risk patients suffering from MCRC. Although the RR was lower in comparison to standard risk cases it did not translate into shorter TTP as well as OS. Similar to ours results were published in various scientific papers. To define a precise role of various optimization strategies of CPT11-based chemotherapy in MCRC, randomized prospective multicenter studies are mandatory. No significant financial relationships to disclose.