Experience with carboplatin and etoposide maintenance chemotherapy in patients with extensive stage small cell lung cancer

Amaan Siddiqi¹, Huzefa Bahrain², Michael Auerbach^1,2
1Georgetown University School of Medicine, ²Auerbach Hematology and Oncology, Baltimore, MD, USA

Purpose: To determine whether maintenance therapy with carboplatin and etoposide improves progression-free and overall survival in patients with extensive stage small cell lung cancer, compared to the standard four to six cycles of cisplatin and etoposide.
Methods: Forty-two patient records (25 males and 17 females) were retrospectively reviewed in a single community practice. All patients were over the age of 18, with pathologically and radiographically proven extensive stage small cell lung carcinoma (SCLC). The starting doses of chemotherapy were carboplatin, AUC (area under the curve) of 6 IV day 1, and etoposide, 100 mg/m² IV days 1–3. The regimen was administered every 3 weeks and increased to every 4 to 5 weeks as tolerated or until documented progression occurred. Varying second-line chemotherapies were used.
Results: Median overall survival was 17 months from diagnosis, with a progression-free survival of 15 months. Seventy-nine percent of the patients survived more than 10 months. The 1- and 2-year overall survival (OAS) rates were 0.74 (31 patients) and 0.31 (13 patients), respectively. The 1- and 2-year progression free survival (PFS) rates were 0.50 (21 patients) and 0.21 (9 patients), respectively.
Conclusion: The improved overall and progression-free survival compared to the current standard in this small single center cohort suggests that maintenance therapy with carboplatin and etoposide to progression may be a prudent area for further investigation in a properly powered randomized, controlled trial.

Keywords: progression-free survival, maintenance therapy, overall survival, metastasis