Real-world use of sunitinib in Japanese patients with pancreatic neuroendocrine tumors: results from a post-marketing surveillance study.
BACKGROUND
Sunitinib is approved for the treatment of progressive, well-differentiated pancreatic neuroendocrine tumors (pNETs) in patients with unresectable, locally advanced or metastatic disease. Safety and efficacy data in Japanese patients are limited. We report outcomes from a post-marketing surveillance study of sunitinib treatment in Japanese patients.


METHODS
Sunitinib 37.5 mg once daily was orally administered in Japanese patients aged ≥ 15 years with pNETs. The primary endpoints included adverse events (AEs) occurring during the observation period of 168 days and objective response rate (ORR).


RESULTS
Sunitinib was administered in 62 patients with pNETs. The median duration of treatment was 165 days. At 168 days from the start of treatment, 31 patients were still receiving sunitinib treatment and treatment continuation rate was 50.0%. Of the 31 patients who discontinued treatment, 18 (58.1%) discontinued because of AEs and 16 (51.6%) patients discontinued due to insufficient clinical effect. Of the 18 patients who discontinued due to AEs, 10 did so within 42 days of treatment initiation. The most common all-grade AEs were platelet count decreased (33.9%), diarrhea (29.0%), neutrophil count decreased (27.4%), hypertension (24.2%), and palmar-plantar erythrodysesthesia syndrome (24.2%). In the 51 patients eligible for the efficacy analysis, ORR was 13.7% (95% confidence interval, 5.7-26.3) and clinical benefit rate was 70.6%.


CONCLUSIONS
There were no new safety concerns in real-world use of sunitinib in Japanese patients with pNETs. The short treatment duration likely led to low tumor response. Appropriate AEs management through dose interruption/reduction is essential for sunitinib treatment success in this patient population.
['Sato|Kazuo|K|', 'Toyoshima|Yasuharu|Y|', 'Moriyama|Shiho|S|', 'Endo|Yutaka|Y|', 'Ito|Tetsuhide|T|', 'Ohki|Emiko|E|']
D000328:Adult D000368:Aged D000970:Antineoplastic Agents D064420:Drug-Related Side Effects and Adverse Reactions D005260:Female D005500:Follow-Up Studies D006801:Humans D015994:Incidence D007564:Japan D008297:Male D008875:Middle Aged D009362:Neoplasm Metastasis D018358:Neuroendocrine Tumors D011358:Product Surveillance, Postmarketing D011379:Prognosis D000077210:Sunitinib
Sunitinib Pancreatic neuroendocrine tumors Safety Objective response rate Japan