Should extrapulmonary small cell cancer be managed like small cell lung cancer?
BACKGROUND
The aim of this study was to determine if extrapulmonary small cell carcinomas (EPSCC) should be managed using protocols similar to those for small cell lung cancer (SCLC).


METHODS
Treatment strategies, survival, patterns of failure, and prognostic factors for patients with EPSCC were analyzed retrospectively at a large cancer center. SCLC was excluded by thoracic computed tomography (75%) or chest radiography (25%).


RESULTS
Of 120 eligible patients, 70% had limited disease (LD). Treatment modalities included chemotherapy (n = 82; 68%), radiotherapy (RT) (n = 80; 67%), and surgery (n = 41, 34%). The median survival for patients with LD and extensive disease was 1.4 years and 0.7 years, respectively. Gynecologic (n = 31) and gastrointestinal (n = 28) were the most common primary tumor sites. Gynecologic and head and neck primary tumor sites had better 1-year survival than other sites (P = .019 and 0.005, respectively). Brain metastasis was the site of first distant failure in 4.1% of patients versus 35% for soft tissue metastases. The lifetime risk of brain metastasis was 13%. Definitive RT (P = .004), LD (P = .028), and prophylactic cranial irradiation (PCI) (P = .022) were found to be positive prognostic factors and weight loss (P < .001) was a negative prognostic factor on multivariate analysis.


CONCLUSIONS
Patients with EPSCC usually experienced short survival, often with early distant metastasis. Although PCI was associated with improved overall survival, brain metastasis was less frequent than in patients with SCLC, and therefore the potential benefit of PCI was less than in patients with SCLC. Definitive chemoradiotherapy was associated with better outcomes and should be delivered whenever feasible.
Brennan
Sinead M
SM
Department of Radiation Oncology, Peter MacCallum Cancer Centre, 12 St. Andrews Place, East Melbourne, Victoria, Australia. sineadbrennan09@gmail.com.
Gregory
Deborah L
DL
Stillie
Alison
A
Herschtal
Alan
A
Mac Manus
Michael
M
Ball
David L
DL
D001932:Brain Neoplasms / Q000517:prevention & control; D018288:Carcinoma, Small Cell / Q000401:mortality / Q000628:therapy*; D003131:Combined Modality Therapy; D016371:Cranial Irradiation; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000473:pathology; D005833:Genital Neoplasms, Female / Q000473:pathology; D006258:Head and Neck Neoplasms / Q000473:pathology; D006801:Humans; D008297:Male; D009382:Neoplasms, Unknown Primary / Q000473:pathology; D010166:Palliative Care; D011379:Prognosis; D012907:Smoking; D014565:Urogenital Neoplasms / Q000473:pathology*; D015431:Weight Loss