Surgical management and role of imatinib therapy in giant gist: a single-based cancer center series

Introduction: Gastrointestinal stromal tumors (GIST) represent 3% of all GIT tumors (Lech, Korcz et al., 2015) and 85% of all mesenchymal tumors of the gastrointestinal tract (GIT), their biological behavior ranges from borderline to malignant depending on the size and the mitotic activity, tumor site, tumor vascularization and infiltration (Lech, Korcz et al. 2015). Patients and methods: This is a retrospective observational study comprising 90 cases of Giant GIST in the National Cancer Institute during the period from 2010 to 2020. Results: All the giant GIST patients underwent surgical resection, including 77 cases (91.7%) of R0 resection, 5 cases (5.9%) of R1 resection and 2 cases (2.4%) of R2 resection, besides, 16 cases (19.2%) underwent multiorgan resection and 24 cases (28.6) underwent lymphadenectomy. Discussion: To our knowledge this is one of the largest series of published Giant GIST. Many case reports of giant rare subtypes of GISTS were published. The incidence of the large size of the tumors in this study is 40.4% which is high compared to the published data estimating that only 20% of GIST tumors present as giant GIST., this is because most of the GIST are diagnosed after reaching very large sizes causing symptoms(Kimura, Togawa et al. 2020). Conclusion: Complete surgical excision combined with targeted therapy imatinib can improve the prognosis significantly whether used in the neoadjuvant setting to downsize the tumor or in the adjuvant setting to decrease recurrences. Overall survival and DFS in this study are excellent and comparable to the literature