3500 - Randomised phase 2 trial of first-line docetaxel, carboplatin, capecitabine (CTX) and epirubicin, oxaliplatin, capecitabine (EOX) in advanced esophagogastric adenocarcinoma (SEED)

Background

Chemotherapy is associated with a survival benefit in advanced gastric cancer. Several options exist, including EOX. The regimen docetaxel, cisplatin and 5-fluorouracil (DCF) is toxic and modifications have been developed. In our institution CTX was a standard treatment from 2004 to 2012 when it was replaced by EOX. Afterwards, a randomised trial with CTX was conducted.

Methods

SEED was a prospective, single-center, phase 2 trial in unresectable HER2-negative esophagogastric adenocarcinoma. Patients were randomised to either docetaxel 60 mg/m², carboplatin AUC5 and capecitabine 1000 mg/m² bd for 14 days q4w (CTX) or epirubicin 50 mg/m², oxaliplatin 130 mg/m² and capecitabine 625 mg/m² bd for 21 days q3w (EOX). Treatment continued until progression, intolerance or a maximum of 9 cycles. The primary endpoint was 1-year-survival for patients treated with CTX. The trial sought to accept (lower boundary 55%) or reject (higher boundary 40%) CTX for further study without making direct comparisons to EOX. Secondary endpoints included OS, PFS and grade 3/4 toxicities.

Results

From 2014 to 2019 a total of 98 patients were randomised (49 in each arm). The median age was 63 (36 - 79). Male/female: 79/19; ECOG PS (0/1): 46/52; oesophageal/GEJ/gastric: 29/44/25; metastatic/non-metastatic: 96/2. As of 26 April 2019, 85 patients had died. The estimated 1-year survival was 32% (95% CI 19 - 46) for CTX and 39% (95% CI 25 - 52) for EOX. The median PFS and OS was 6.2 months (95% CI 5.2 - 7.2) and 9.2 months (95% CI 7.2 - 11.2), respectively, for CTX, and 5.2 months (95% CI 3.5 - 7.0) and 10.2 months (95% CI 7.9 - 12.4), respectively, for EOX. Grade 3/4 related toxicities in > 5% were neutropenia (78%), febrile neutropenia (25%), diarrhoea (8%) and fatigue (6%) for CTX, and neutropenia (49%), febrile neutropenia (10%), peripheral neuropathy (8%) and nausea (8%) for EOX. There were no treatment-related deaths.

Conclusions

CTX resulted in a 1-year-survival rate of 32% and so is rejected for further study. Also, CTX had a high rate of febrile neutropenia. CTX is not recommended for patients with esophagogastric cancer, except selected patients intolerant of other standard therapies, and then only with G-CSF support.

Clinical trial identification

NCT02177552.

Editorial acknowledgement

Legal entity responsible for the study

Lene Baeksgaard.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.