Endocrine Abstracts (2019) 68 P12 | DOI: 10.1530/endoabs.68.P12

Systemic chemotherapy for inoperable Goblet Cell Adenocarcinomas (GCAs)

Jorge Barriuso1, Angela Lamarca1, Amy Martin2, Bipasha Chakrabarty1, Hamish Clouston1,3, Saifee Mullamitha4, Mairéad McNamara1, Francisca Marti-Marti4, Richard Hubner1, Mark Saunders4, Sarah O’Dwyer1,3, Michael Braun4 & Juan Valle1

1The Christie ENETS Centre of Excellence, Manchester, UK; 2Beatson West of Scotland Cancer Centre, Glasgow, UK; 3The Christie Colorectal and Peritoneal Oncology Centre, Manchester, UK; 4The Christie NHS Foundation Trust, Manchester, UK

Background: Appendiceal GCAs (previously known as Goblet Cell Carcinoids) are considered to have an unpredictable behaviour; even in node-negative patients, metastases mainly local to the adjacent peritoneum are seen. The systemic chemotherapy (scx) is often borrowed from colon cancer regimens. We designed a retrospective study with the aim of describing the use of scx in these rare malignancies in our institution.

Methods: Data from all consecutive cases of inoperable GCAs treated at The Christie ENETS Centre of Excellence were collected. Statistical analysis was performed using IBM SPSS 19. Univariate survival analysis was performed using Kaplan–Meier curves, log-rank text and univariate (UV) / multivariable (MV) Cox regression.

Results: Thirty-seven patients were elegible. Median follow up was 22 months (ms). Median age was 53 years range 26–70. The female:male ratio was 3:2. The stage at diagnosis was IV for 26 (70.3%) patients (pts). All were stage-IV before initiating scx. The majority were Tang B or C (83.8%). R0 resection at the initial surgery was achieved for 75% of pts. The performance status at the initiation of the scx was ECOG 0 or 1 in 83.3%. Nine pts (24.3%) received prior adjuvant treatment with scx. First line treatment was based on oxaliplatin in 69.7% of the pts. The median overall survival (OS) for the full cohort was 22 ms, 95% CI: 14.3–29.8. The median progression free survival (PFS) was 5.8 ms, 95% CI: 4.4–7.1. No complete responses (CR) were observed. The overall response rate was 24%, 95% CI: 12%–43%. The disease control rate (partial response plus stable disease) was 80%, 95% CI: 60%–91%. There were no differences in PFS or OS between oxaliplatin based scx vs others, P=0.76 and P=0.70 respectively. The stage at diagnosis was a statistically significant in the log-rank test for OS and PFS, P=0.033 and P=0.014 respectively. No other factor was significant in the UV analyses and when adjusted for Tang or resection margins the stage did not retain its statistically significance for OS and PFS.

Conclusion: Patients with GCAs benefited from systemic chemotherapy when relapse after the initial surgery occurred and a surgical operation could not be performed.