Sinonasal Neuroendocrine Carcinoma: 15 Years of Experience at a Single Institution

Abstract

Objectives Sinonasal neuroendocrine carcinomas (SNECs) are among the rarest paranasal sinus cancers. Consensus guidelines for therapy are difficult to develop due to limited data regarding the natural history and successful treatment of these tumors. This study presents 15 years of experience treating SNEC at a single institution and a review of the literature. Design Retrospective review. Setting Academic medical center in the United States. Participants Patients diagnosed with primary SNEC. Main Outcome Measures Overall survival. Results Thirteen patients were identified and included. Overall estimated survival was 74.6% at 5 years. Ten of 13 (76.9%) patients were diagnosed with high-grade neuroendocrine carcinoma and three (23.1%) with intermediate or low grade. All three patients with low- or intermediate-grade cancer survived more than 10 years from their initial diagnosis (median survival: 11.6 years) and are currently alive. The four patients who died had high-grade carcinoma, and estimated overall 5-year survival for all patients with high-grade carcinomas was 65.6%. Five patients, all with high-grade carcinoma, of seven who completed primary chemoradiation therapy (CRT) required salvage resection, and 60% are alive without disease. Conclusion This cohort has a higher overall rate of survival than many recent case series and reviews. There is consensus that multimodal therapy is preferred over monotherapy, but approaches to treatment vary widely. Our approach of surgical resection as primary therapy for low-grade tumors and primary CRT for high-grade SNEC has been successful, and could indicate hope for improved survival among these patients.

Poorly differentiated sinonasal neuroendocrine carcinoma with skull base invasion: A case report

“…Sinonasal undifferentiated NEC is relevant because the only current factor in response to treatment and survival is histological grade; suspicion is limited to nonspecific symptoms even in advanced stages, and the majority of cases (75.0–84.6%) are diagnosed at stage IV,[ 11 , 17 , 23 ] when there is already invasion to the skull base, orbit, or brain. Its prevalence peaks between the 5 th and 6 th decades of life, with a slight male predisposition;[ 11 ] however, there are no identified risk factors.…”

“…Regarding the treatment of persistent high-grade lesions, salvage resection has been shown to be a potentially curative option; one cohort demonstrated a disease-free survival of 60% following salvage surgery. [ 11 ]…”

“…Enasidenib is an anti-IDH2 agent that could be incorporated into the therapeutic regimen for recurrent lesions. [ 7 ] In addition, a recent cohort analysis found the use of octreotide, a somatostatin analog, as an effective antiproliferative treatment in residual low-grade lesions after surgery;[ 11 ] however, it has not yet been fully studied.…”

“…However, the low degree of histologic differentiation found has been associated with overall survival as low as 30.8–40.0% at 5 years in representative studies. [ 11 , 22 ] Some other negative prognostic factors reported are high TNM stage, lymph node metastasis, Ki-67> 55%, and skull base infiltration[ 18 ] which give greater relevance to the follow-up of this patient.…”

“…Sinonasal neuroendocrine differentiation accounts for only 5% of all neoplasms in this region; it was first described 30 years ago, and by 2016, only 242 published cases were found. [ 11 ]…”