Gemcitabine in patients previously treated with platinum-containing chemotherapy for refractory thymic carcinoma: radiographic assessment using the RECIST criteria and the ITMIG recommendations

The key drugs for chemotherapy of thymic carcinoma are gradually being revealed in phase II and conventional retrospective studies. Gemcitabine is regarded as one of these key drugs according to the findings of clinical trials in which it was combined with capecitabine. However, the activity of single-agent gemcitabine concerning refractory thymic carcinoma remains unclear. We conducted a retrospective review of the medical records of refractory thymic carcinoma patients previously treated with platinum-containing chemotherapy between 1980 and 2014. Of all 11 patients in this study, the objective response rate regarding gemcitabine was 36.4 % [95 % confidence interval (CI) 15.2-64.6] using the RECIST criteria and the response criteria proposed by the ITMIG. The median progression-free survival time was 4.3 months (95 % CI 0.7-11.0). The survival time from the start of gemcitabine treatment was 28.5 months (95 % CI 5.5-47.8), and from the start of first-line chemotherapy was 46.5 months (95 % CI 7.3-47.8). Gemcitabine achieved a moderate response and has the potential to be used as a key drug for thymic carcinoma. Some patients treated with gemcitabine demonstrated prolonged cancer control even in later lines of chemotherapy.