Angelena Crown1,2, Vlad V Simianu1,2, Hagen Kennecke1, Alexandra G Lopez-Aguiar3, Mary Dillhoff4, Eliza W Beal4, George A Poultsides5, Eleftherios Makris5, Kamran Idrees6, Paula Marincola Smith6, Hari Nathan7, Megan Beems7, Daniel Abbott8, James Barrett8, Ryan C Fields9, Jesse Davidson9, Shishir K Maithel3, Flavio G Rocha10,11. 1. Digestive Disease Institute, Virginia Mason Medical Center, Seattle, WA, USA. 2. Section of General, Thoracic and Vascular Surgery, Virginia Mason Medical Center, 1100 Ninth Av, Seattle, WA, 98101, USA. 3. Division of Surgical Oncology, Department of Surgery, Winship Cancer Institute, Emory University, Atlanta, GA, USA. 4. Division of Surgical Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA. 5. Department of Surgery, Stanford University Medical Center, Stanford, CA, USA. 6. Division of Surgical Oncology, Department of Surgery, Vanderbilt University Medical Center, Nashville, TN, USA. 7. Division of Hepatopancreatobiliary and Advanced Gastrointestinal Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI, USA. 8. Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA. 9. Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA. 10. Digestive Disease Institute, Virginia Mason Medical Center, Seattle, WA, USA. flavio.rocha@virginiamason.org. 11. Section of General, Thoracic and Vascular Surgery, Virginia Mason Medical Center, 1100 Ninth Av, Seattle, WA, 98101, USA. flavio.rocha@virginiamason.org.
Abstract
BACKGROUND: Appendiceal neuroendocrine tumors (A-NETs) are rare neoplasms of the GI tract. They are typically managed according to tumor size; however, the impact of surgical strategy on the short- and long-term outcomes is unknown. METHODS: All patients who underwent resection of A-NET at 8 institutions from 2000 to 2016 were analyzed retrospectively. Patient clinicopathologic features and outcomes were stratified according to resection type. RESULTS: Of 61 patients identified with A-NET, mean age of presentation was 44.7 ± 16.0 years and patients were predominantly Caucasian (77%) and female (56%). Mean tumor size was 1.2 ± 1.3 cm with a median of 0.8 cm. Thirty-one patients (51%) underwent appendectomy and 30 (49%) underwent colonic resection. The appendectomy group had more T1 tumors (87% vs 42%, p < 0.01) than the colon resection group. Of patients in the colon resection group, 27% had positive lymph nodes and 3% had M1 disease. R0 resections were achieved in 90% of appendectomy patients and 97% of colon resection patients. Complications occurred with a higher frequency in the colon resection group (30%) compared with those in the appendectomy group (6%, p = 0.02). The colon resection group also had a longer length of stay, higher average blood loss, and longer average OR time. Median RFS and OS were similar between groups. CONCLUSION: A-NET RFS and OS are equivalent regardless of surgical strategy. Formal colon resection is associated with increased length of stay, OR time, higher blood loss, and more complications. Further study is warranted to identify patients that are likely to benefit from more aggressive surgery.
BACKGROUND:Appendiceal neuroendocrine tumors (A-NETs) are rare neoplasms of the GI tract. They are typically managed according to tumor size; however, the impact of surgical strategy on the short- and long-term outcomes is unknown. METHODS: All patients who underwent resection of A-NET at 8 institutions from 2000 to 2016 were analyzed retrospectively. Patient clinicopathologic features and outcomes were stratified according to resection type. RESULTS: Of 61 patients identified with A-NET, mean age of presentation was 44.7 ± 16.0 years and patients were predominantly Caucasian (77%) and female (56%). Mean tumor size was 1.2 ± 1.3 cm with a median of 0.8 cm. Thirty-one patients (51%) underwent appendectomy and 30 (49%) underwent colonic resection. The appendectomy group had more T1 tumors (87% vs 42%, p < 0.01) than the colon resection group. Of patients in the colon resection group, 27% had positive lymph nodes and 3% had M1 disease. R0 resections were achieved in 90% of appendectomy patients and 97% of colon resection patients. Complications occurred with a higher frequency in the colon resection group (30%) compared with those in the appendectomy group (6%, p = 0.02). The colon resection group also had a longer length of stay, higher average blood loss, and longer average OR time. Median RFS and OS were similar between groups. CONCLUSION: A-NET RFS and OS are equivalent regardless of surgical strategy. Formal colon resection is associated with increased length of stay, OR time, higher blood loss, and more complications. Further study is warranted to identify patients that are likely to benefit from more aggressive surgery.