Efficacy and safety of high-dose prednisone for patients with advanced thymoma: a retrospective study

Background: Chemotherapeutic treatments for advanced thymoma have limited efficacy and a high rate of adverse events, while it has been reported that glucocorticoids (GCs) may be effective in this context. This study aimed to retrospectively analyze the efficacy and safety of high-dose prednisone for patients with advanced thymoma in a single center in order to determine the optimal application scenarios for GCs in the treatment of these patients.

Methods: Patients with previously treated advanced tumor-node-metastasis (TNM) (8^th edition) stage III–IV thymomas that received treatment with high-dose prednisone (0.5–1 mg/kg/day) in Shanghai Chest Hospital were included. Clinical characteristics, response to prednisone, type of subsequent treatment, and adverse events were analyzed.

Results: A total of 26 patients were included, with 15 (57.7%) having primary stage III–IV diseases and 11 (42.3%) having pleural recurrent stage IV diseases. The objective response rate (ORR) of prednisone was 57.7% (15/26), with 2 cases of complete response (CR) and 13 cases of partial response (PR). Ten (38.5%) patients had stable disease (SD), and 1 (3.8%) had progressive disease (PD). All patients had type B thymomas. The ORR was relatively higher in type B1 tumors than in the other subtypes (71.4% vs. 37.5%, P=0.19). Of the 26 patients, 16 (61.5%) received subsequent surgery and complete resection of the visible tumors, 5 (19.2%) received radiotherapy, 2 received long-term treatment of prednisone, and 3 were scheduled for follow-up. Three cases of pneumonia and one case of hypertension and diabetes were recorded during the treatment. After prednisone treatment, patients with PR or CR had significantly better progression-free survival (PFS) than did those with SD or PD (P=0.045).

Conclusions: High-dose prednisone is effective and safe for the treatment of advanced thymoma. It might be particularly effective in induction therapy before surgery or in creating the opportunity for radiotherapy. The long-term administration of prednisone should be selected with careful consideration of its potential side effects.