Metastatic thymic epithelial tumors: A regional cancer center experience

Abstract

Background: Thymic epithelial tumors (TET) are the most common tumors of the anterior mediastinum. Patients with advanced/metastatic disease are usually treated with palliative chemotherapy (CT). Unfortunately, even though various palliative CT regimens have been used for long time, there is a real scarcity of published Indian data regarding the experience of palliative CT in metastatic TET (mTET).

Materials and methods: This is a retrospective analysis of mTET patients treated between January 2010 and September 2017. Patients who received at least three cycles of first-line palliative CT were included for analysis of response rates, toxicity, and survival and prognostic factors.

Results: Of the 49 mTET patients, 27 (55.1%) were males. The median age at diagnosis was 52 years (range: 25-65). Eighteen patients (36.7%) had Masaoka Stage IVa disease, and the rest of the patients had IVb disease. The most common site of metastasis was pleuropericardium (n = 18), followed by lungs (n = 16) and lymph nodes (n = 9). The median progression-free survival and overall survival (OS) were 11.2 months (95% confidence interval [CI], 8.7-13.6) and 20.2 months (95% CI, 17.1-22.8), respectively, for the whole cohort (n = 49). The median OS of patients with Stage IVa disease was significantly better than that of the patients with Stage IVb disease (log-rank P = 0.000). Moreover, the "responders" to first-line CT had a significantly better median OS than the "nonresponders" (log-rank P = 0.000). Various first-line palliative CT regimens were well tolerated in our patients.

Conclusion: Adriamycin Cisplatin Vincristine Cyclophosphamide (ADOC), Cyclophosphamide Adriamycin Cisplatin, and paclitaxel + carboplatin all are viable first-line palliative CT options for mTET and showed a comparable survival in Indian patients. The present study suggested that "responders" to first-line CT and those with Stage IVa disease might have a better survival than "nonresponders" and those with Stage IVb disease, respectively.

Keywords: ADOC regimen; metastatic thymic epithelial tumors; palliative chemotherapy.