Comparison of anthracycline plus platinum versus other platinum-based regimens as first-line chemotherapy for untreated thymoma: A retrospective cohort study (NEJ023B).

BACKGROUND

Optimal management of advanced thymoma remains uncertain. We compared the efficacy of first-line platinum-anthracycline chemotherapy with other platinum-based regimens in a large Japanese cohort.

METHODS

We retrospectively analyzed 157 patients with unresectable or recurrent thymoma treated at 39 institutions (2000-2020). Regimens were categorized as platinum-anthracycline (n = 104) or non-anthracycline platinum (n = 53). Propensity score matching (PSM) balanced baseline characteristics (46 pairs). The primary endpoint was overall response rate (ORR); secondary endpoints were real-world progression-free survival (rwPFS) and overall survival (OS).

RESULTS

Median age was 58 years (24-79) and 53% were male; 62% had recurrent disease. Before PSM, ORR was higher with platinum-anthracycline than with non-anthracycline platinum (57% vs 31%; p = 0.0024), while rwPFS (median 15.0 vs 13.4 months; HR 1.07; p = 0.72) and OS (median 84.9 vs 111.9 months; HR 1.36; p = 0.24) did not differ. After PSM, ORR remained higher (58% vs 32%; p = 0.0014) with comparable rwPFS (12.1 vs 11.7 months; HR 0.98; p = 0.98) and OS (93.8 vs 113.5 months; HR 1.41; p = 0.31). Overall, 70% of patients received subsequent local therapy. Among fatal cases, paraneoplastic syndromes occurred in 50%, and infections and cardiovascular events were frequent causes of death in addition to tumour progression.

CONCLUSIONS

Although platinum-anthracycline regimens achieved higher response rates, this did not translate into longer rwPFS or OS. Non-anthracycline platinum regimens may be reasonable for selected patients, particularly when treatment tolerability is a priority, within individualized multidisciplinary long-term management.

TRIAL REGISTRATION: UMIN000048181.