PGY2 Oncology Pharmacy Resident Emory University Hospital Midtown, Winship Cancer Institute Atlanta, Georgia, United States
Poster Abstract:
Background: Soft tissue sarcoma (STS) is a rare and heterogenous type of sarcoma, with various histological subtypes and differences in staging, clinical course, and management. Anthracycline-based chemotherapy (single-agent or combination) is the mainstay of treatment for metastatic STS, though significant toxicities occur. Gemcitabine-based regimens may be used as initial treatment in patients who cannot tolerate anthracycline-based regimens.[1,2] The combination of gemcitabine plus vinorelbine has limited evidence in advanced STS, though may show response in up to 25% of patients.[2] The purpose of this study is to assess efficacy and safety of gemcitabine plus vinorelbine in STS.
Objectives: The primary objective of the study is progression free survival. Secondary objectives include incidence of treatment-related adverse events, clinician assessed clinical benefit, and comparison of efficacy and safety data to historical cohorts of doxorubicin and docetaxel plus gemcitabine.[3]
Methods: A single-center, retrospective cohort study of STS patients was conducted between 01/01/2010 to 5/1/2023. Subjects were included if they were at least 18 years old; had histology confirmed, unresectable, locally advanced, or metastatic STS; received at least one dose of combination gemcitabine plus vinorelbine; and had no other active malignancy. Patients were excluded if they were on clinical trial or had concomitant use of other chemotherapy agents during the intervention regimen.
Results: One-hundred patients met inclusion criteria. Most patients were diagnosed with leiomyosarcoma (48%), and the median number of previous therapy lines was 1 (range 0 to 8). Sixteen (16%) patients had a therapy change due to toxicity; any-grade hematologic and non-hematologic toxicities occurred in 95 (95%) and 64 (64%) patients, respectively. Grade 3 or 4 hematologic toxicities of anemia, neutropenia, leukopenia and thrombocytopenia occurred in 17 (17%), 16 (16%), 6 (6%) and 5 (5%) patients, respectively. The most common any-grade nonhematologic toxicities were fatigue (31 patients [31%]), nausea/vomiting (24 [24%]), infection without neutropenia (21 [21%]), and constipation (12 [12%]). Grade 3 or 4 non-hematologic toxicities occurred in 8 (8%) patients. Final efficacy results are pending.
Discussion/
Conclusion: The gemcitabine plus vinorelbine chemotherapy combination was well tolerated among a patient population with advanced STS that received prior therapy. Incidence of grade 3 or 4 hematologic toxicities was similar to incidence reported in other studies, though grade 3 or 4 neutropenia was lower in this study.[2,3] Further analysis will add to the literature for the efficacy of the gemcitabine and vinorelbine regimen.
References (must also be included in final poster): [1] Demetri GD, Baker LH, Beech D, Benjamin R, Casper ES, Conrad EU 3rd, DeLaney TF, Ettinger DS, Heslin MJ, Hutchinson RJ, Kiel K, Kraybill WG, Letson GD, Neff J, O'Donnell RJ, Paz IB, Pollock RE, Randall RL, Schupak KD, Tyler DS, von Mehren M, Wayne J; National Comprehensive Cancer Network. Soft tissue sarcoma clinical practice guidelines in oncology. J Natl Compr Canc Netw. 2005 Mar;3(2):158-94. PMID: 19817028; PMCID: PMC5788173. [2] Dileo P, Morgan JA, Zahrieh D, et al. Gemcitabine and vinorelbine combination chemotherapy for patients with advanced soft tissue sarcomas: results of a phase II trial. Cancer. 2007;109(9):1863-1869. doi:10.1002/cncr.22609 [3]Seddon B, Strauss SJ, Whelan J, et al. Gemcitabine and docetaxel versus doxorubicin as first-line treatment in previously untreated advanced unresectable or metastatic soft-tissue sarcomas (GeDDiS): a randomised controlled phase 3 trial. Lancet Oncol. 2017;18(10):1397-1410. doi:10.1016/S1470-2045(17)30622-8
