Trimodality treatment in Stage III nonsmall cell lung carcinoma: prrognostic impact of K-ras mutations after neoadjuvant therapy

Abstract

Background: In a trimodality treatment approach for Stage III nonsmall cell lung carcinoma (NSCLC), the prognostic impact of the ras mutation status in resection specimens was evaluated.

Methods: Forty patients with Stage III NSCLC underwent tumor resection after neoadjuvant treatment with two cycles of chemotherapy (ifosfamide, carboplatin, and etoposide) and subsequent twice-daily radiotherapy (45 grays [Gy]; 2 x 1.5 Gy/day) with concurrent carboplatin and vindesine. Assessment of K-ras codon 12 mutation status was performed in the paraffin embedded resection specimens by a two-step polymerase chain reaction followed by restriction fragment length polymorphism analysis.

Results: K-ras mutation status could be assessed in 28 cases. A K-ras codon 12 point mutation was found in 13 of 28 resection specimens (46%). The mutation was found independently of gender, age, tumor stage, and clinical response status and occurred more frequently in adenocarcinomas. Even after complete resection, the presence of a K-ras mutation was a significant predictor for a poor progression free survival (P = 0.005).

Conclusions: These data suggest that further evaluation of the K-ras codon 12 mutation status in trials on neoadjuvant and adjuvant therapy is warranted. This may contribute to the identification of stratification variables for future treatment approaches.