EORTC LCCG Phase II study of topotecan in combination with cisplatin as second line chemotherapy of sensitive and refractory small cell lung cancer (SCLC)

Treatment of relapsed small-cell lung cancer--a focus on the evolving role of topotecan

Despite the high response rates to chemotherapy, small-cell lung cancer (SCLC) is among the most lethal malignancies. Long-term survival is anecdotal for patients with extensive disease; 5-years survival is < or =5% for those with limited disease. All patients with extensive disease and most patients with limited disease will experience disease progression and become candidates for second-line therapy. Although a number of agents have demonstrated antitumor activity in relapsed SCLC, including paclitaxel, docetaxel, etoposide, cisplatin, and carboplatin, topotecan is the only single agent currently approved in the United States for the treatment of recurrent disease. Topotecan is a novel topoisomerase I inhibitor with established antitumor activity in recurrent SCLC and has a predictable, noncumulative toxicity profile. Furthermore, topotecan has been shown to provide symptom improvement in this predominantly palliative setting. Evidence also suggests that topotecan readily penetrates the blood-brain barrier and might be active in the relatively large subset of SCLC patients who experience brain metastases. This article reviews the clinical utility of topotecan in recurrent SCLC, including its efficacy, tolerability, and quality-of-life effect, when used as monotherapy and in novel combination regimens.

Chemotherapy as treatment of primary and recurrent small cell lung cancer

Chemotherapy is the treatment of choice in metastatic stage of small-cell lung cancer (SCLC). Radiation therapy, surgery and other forms of therapy are only included in special treatment situations, particularly for different local problems. A wide range of chemotherapeutic agents have proven to be effective in SCLC, including carboplatin, cisplatin, cyclophosphamide, doxorubicin, epirubicin, etoposide, ifosfamide, teniposide and vincristine. However, treatment results could not be improved over the last 10 years and the median survival of patients with metastatic disease is limited to 7-10 months. New agents like docetaxel, gemcitabine, irinotecan, paclitaxel, topotecan and vinorelbine have shown promising results in phase-II investigations. Yet, no evidence is provided from randomized trials to employ these drugs in first line treatment. Clearly, polychemotherapy is superior to single agent treatment. Compared to the combination of cisplatin and etoposide, no other combination has clearly shown improved results in large phase-III randomised trials, yet. The combination of cisplatin and irinotecan has also shown promising results in a single randomised trial with the need to be confirmed in larger settings. Neither extending the initial treatment beyond the median number of six cycles, nor maintenance treatment have-so far-resulted in any increase in survival results for patients with metastasised SCLC. Nor has dose-intensification, which causes significantly higher toxicities in patients, shown a clear impact on the overall survival of these patients. Brain metastases represent a high frequent complication associated with SCLC. In these cases, the combination of chemotherapy and whole brain radiation therapy is advocated. Second-line treatment should always be considered in patients with relapse or failure to first-line therapy. In addition to a rechallenging with the prior drug combination or selecting a different potentially non-cross resistant one, monotherapy with topotecan proved to be effective as well. In summary, up to now, no standard chemotherapy combination exists for metastatic SCLC. The individual therapy strategy can only be selected by considering the clinically relevant conditions of the patient.