Adding Paclitaxel May Improve Survival in Limited-Disease SCLC

NEW ORLEANS—The addition of paclitaxel (Taxol) to etoposide plus cisplatin (Platinol), with concurrent thoracic radiotherapy, may improve survival in patients with limited-disease small-cell lung cancer (SCLC), according to preliminary results from the RTOG 96-09 Intergroup trial. David S. Ettinger, MD, of Johns Hopkins Oncology Center, presented the study at the 36th Annual Meeting of the American Society of Clinical Oncology (ASCO).

The aim of this trial was to improve upon the results of a prior Intergroup study (N Engl J Med 340:265-271, 1999), which showed a 1-year survival of 70% and median survival of 23 months for etoposide/cisplatin and concurrent radiotherapy.

The phase II study included 55 patients with limited-disease SCLC treated with cisplatin (60 mg/m² on day 1), oral etoposide (80 mg/m² on days 2 and 3), and paclitaxel (135 mg/m² on day 1 given over 3 hours) every 3 weeks for four cycles of therapy.

Thoracic radiotherapy was given concurrently with cycle 1 (1.5 Gy fractions twice a day for 5 days a week for 3 weeks for a total dose of 45 Gy). For cycles 2 to 4, the dose of paclitaxel was increased to 175 mg/m² with etoposide and cisplatin given as in cycle 1.

Of 51 evaluable patients, 41 (80%) achieved a complete response with this regimen. The 1-year survival was 83%, progression-free survival 51%, and median survival 24.4 months, he said.

In the discussion session of the moderated poster session, Richard Gralla, MD, of Columbia University, labeled this trial “a phase II study with particularly attractive results” and “a surprisingly high response rate.”

Dr. Gralla offered a note of caution, however, in interpreting the results, based on the fact that the study population was relatively young (median age, 56) and about half were females. “This is not what we really expect to see in everyday practice . . . [although] this study does look interesting,” he noted.

The major hematologic toxicities were as follows: neutropenia grade 3 (32%) and grade 4 (43%); thrombocytopenia grade 3 (4%) and grade 4 (4%); anemia grade 3 (9%). Nonhematologic toxicity included esophagitis grade 3 (32%) and grade 4 (4%); nausea and vomiting grade 3 (15%) and grade 4 (4%); lung toxicity grade 3 (9%); and neurologic toxicity grade 3 (6%).

There were two treatment-related deaths and one late fatal pulmonary event. The investigators noted that toxicity in this regimen was similar to regimens without paclitaxel.

Dr. Ettinger said that more time must pass before a definitive statement can be made regarding improvement in survival with the addition of paclitaxel to the standard regimen.

A phase III study comparing concurrent hyperfractionated thoracic radiotherapy with either cisplatin/etoposide/paclitaxel (PET) or etoposide/cisplatin (EP) in patients with limited-disease SCLC is planned.