Urgent need for consensus: international survey of clinical practice exploring use of platinum-etoposide chemotherapy for advanced extra-pulmonary high grade neuroendocrine carcinoma (EP-G3-NEC)

Background Platinum-etoposide (PE) chemotherapy (CH) is a globally established combination for extra-pulmonary high grade neuroendocrine carcinoma (EP-G3-NEC); the optimal schedule has not been established. Methods An international survey was designed, and completed by clinicians with an expertise in the field to assess consistency in clinical practice. Results Seventy-five replies were received (June-Nov’17). A minority of physicians (13; 17.6%) did not take Ki-67 or morphology (9; 12.0%) into consideration for selection of CH. Most (72; 96.0%) selected PE-CH as first-line treatment for EP-G3-NEC. CH schedules varied: cisplatin-based (37/71; 52.1%), carboplatin-based (34/71; 47.9%); intravenous etoposide (64/71; 90.1%), oral etoposide (7/71; 9.9%). Choice of second-line CH depended on time to progression on PE-based first-line: if > 6 months, re-challenge with PE was the preferred choice (34; 45.9%); if < 6 months, alternative combinations such as fluoropyrimidine/irinotecan (21; 29.2%) or temozolomide/capecitabine (22; 30.6%) were used. Conclusion Significant variation in PE regimen employed exists. Standardising clinical practice would facilitate clinical trial development.