Background: The objective of this study was to analyze prognostic factors for survival and to assess the applicability of Kohne's classification in patients treated with irinotecan- or oxaliplatin-based first-line chemotherapy.
Patients and methods: One hundred forty-two consecutive cases from a single center were retrospectively reviewed. Median patient age was 62 years. Sixty percent were men. Eastern Cooperative Oncology Group (ECOG) performance status (PS) was 0/1 in 88%. Primary tumor resection (PTR) was performed in 80.6% of patients who initially had stage IV disease. Chemotherapy consisted of fluoropyrimidines or raltitrexed plus irinotecan (50.5%), oxaliplatin (38.5%), or both (11%). Univariate and multivariate analyses for survival were performed using pretreatment patient characteristics.
Results: Median follow-up was 33.9 months and median overall survival was 15.9 months. Significantly unfavorable prognostic factors were PTR not being performed, disease involvement of >1 organ, liver metastases, undifferentiated histology, EGOG PS>1, increased serum carcinoembryonic antigen and cancer antigen 19.9 levels, hypoalbuminemia, leucocytosis, and elevated alkaline phosphatase and lactate dehydrogenase (LDH) levels. Only ECOG PS, PTR, increased LDH level, no hypoalbuminemia, and number of organs involved retained prognostic value in the multivariate analysis. The incidence and median survival for Kohne's prognostic groups were as follows: good (54.2%; 20 months), intermediate (26.8%; 15.7 months), and poor (19%; 6.8 months). For patients with stage IV disease at presentation, PTR was associated with a significantly longer survival, mainly in patients with an ECOG PS of 0/1.
Conclusion: Eastern Cooperative Oncology Group PS, PTR, serum albumin, increased LDH levels, and organ involvement were the main prognostic indicators in our series. Kohne's prognostic groups, developed in the era of 5-fluorouracil treatment, also seem to be applicable to patients treated with combination chemotherapy. Primary tumor resection should always be considered, especially in patients with an ECOG PS of 0/1. However, the benefit of PTR and multiple-agent chemotherapy is questionable in patients with an ECOG PS of >1.