Second-Line Chemotherapy of Advanced Colorectal Cancer: Predictive and Prognostic Factors

Background: Colorectal cancer progression presents a significant clinical problem. After its dissemination, the foundation of its treatment comprises of palliative chemotherapy.

Objectives: The aim of this study was to assess the predictive and prognostic value of clinical response to second line treatment (with capecitabine or with a two-drug regimen including irinotecan) and to analyze its relation to selected clinical and pathological variables with respect to time to disease progression.

Material and methods: The retrospective analysis of 164 patients with advanced colorectal cancer treated in 2001- -2008 included chosen clinical, pathological and follow-up data.

Results: Response to second-line chemotherapy was observed in 34 out of 164 patients: In 18/82 in the irinotecan group (22%) and in 16/82 in the capecitabine group (19.5%). The mean survival time to progression following the second line of treatment amounted to 5.85 and 6.2 months respectively. Statistically, a higher number of patients in good condition of 0 to 1 was documented in the group responding to treatment. Significant correlation was documented between primary stage of the disease and time to progression in patients treated with capecitabine (p = 0.0258). The recurrence of the disease was observed in 44/45 patients following operation with radical intention but with an insufficient number of excised lymph nodes. A significantly longer time to progression was observed in women treated with capecitabine. In logistic regression, lack of treatment response was found to be an independent factor affecting the time to disease progression. Patients who did not respond to the second line of treatment demonstrated a significantly shorter time to disease progression than patients who responded to it and they showed a significantly higher number of patients with leucopenia during treatment.

Conclusions: Clinical response to treatment in both treated groups is of significant importance for the probability of local recurrence of the disease, preservation of a good patient's condition and the higher level of leukocytes during treatment.