Abstract 1172P
Background
Extra-pulmonary (EP) neuroendocrine carcinomas (NECs) patients (pts) are mostly treated with cis/carboplatinum (CDDP/CBCDA) plus etoposide (E) regimen assuming a similar biologic behaviour to small-cell lung cancers (SCLCs) but they seem to be a category of more heterogenous neoplasms than expected. We provided the outcomes of EP-NECs pts and explored the potential correlation with clinical/biological factors.
Methods
Clinical and biological data of EP-NECs pts treated at the European Institute of Oncology (Milan) between 2001 and 2019 were retrospectively analysed.
Results
Primary sites among a 133 pts were 47% gastro-entero-pancreatic (GEP), 20% urinary (u) and 14% gynaecologic (g) tract, 3% head&neck (H&N), 3% other-NECs (including thymus and adrenal gland) and 10% unknown-primary (UP) origin. Males were 50%, 38% of pts had concomitant/previous other neoplasms (74% in u-NECs subcategory), 62% of pts had synchronous metastases. Median (m) age was 58 years (yrs) (16-89). Pts ≤50 yrs represented 26% of the sample and they mostly had g-NECs. Eighty-one percent received CDDP/CBCDA+E (60% as first line treatment), 52% non-NECs oriented regimens (65% as second or further lines). Whole population m-overall survival (OS) was 15.6 months (range 8.4-30). At the univariate analysis, a significantly better OS was reported only for surgery of the primary (p=0.002). At the multivariate analysis, male gender and synchronous metastases were associated to a significantly worse prognosis (p=0.026 and p<0.001 respectively). EP-NECs with Ki-67 <55% (“NEC-low”) were 16%, mostly from GEP and unknown origin. Low and “high-NECs” (NECs with Ki-67 ≥55%) did not significantly differ in terms of OS, progression-free survival (PFS) and objective response rate to first line CDDP/CBCDA + E.
Conclusions
The retrospective analysis suggested that Ki-67 55% cut-off, unlike previous reports about GEP-NECs pts, did not influence the prognosis of a more heterogenous EP-NECs population. Our analysis generated interesting hypotheses to be prospectively validated in a more homogeneous NECs population.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.