Dylan Bush1, Matt Skovgard1, Sanaa Raoof2, Antonios Sideris1, Xingzhe Li2, Hakeem Oufkir1, Michael Curry3, Kay See Tan3, Jose Araujo-Filho4, Eric Robinson1, David Jones1, Michelle Ginsberg4, Andreas Rimner2, Gregory Riely5, James Huang1
1Department of Surgery, Thoracic Service, Memorial Sloan Kettering Cancer Center, New York, NY, USA;
2Department of Radiation Oncology, Thoracic Radiation Oncology Service, Memorial Sloan Kettering Cancer Center, New York, NY, USA;
3Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, USA;
4Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA;
5Department of Medicine, Thoracic Oncology Service, Memorial Sloan Kettering Cancer Center, New York, NY, USA
Correspondence to: James Huang, MD. Department of Surgery, Thoracic Service, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New Yor, NY 10025, USA. Email: huangj@mskcc.org.
Background: Although surgery is generally considered to be the mainstay of treatment for thymic malignancies, some patients are deemed inoperable or are found to be unresectable. The benefits of an incomplete resection (IR) remain unclear. We sought to define the characteristics, reasons for unresectability, and long-term outcomes in patients with unresectable or inoperable thymic tumors.
Methods: Retrospective review of patients with unresectable or inoperable thymic tumors treated at Memorial Sloan Kettering Cancer Center between 1996–2023. Patients who had surgical exploration only (EO) without any resection, surgical exploration with incomplete (R2) resection, and patients who were deemed unresectable or inoperable and treated non-operatively were included in the study cohort. Descriptive statistics and Kaplan-Meier survival analyses were performed.
Results: Seventy-eight patients were treated over the study period, 43 with thymoma (55%), 31 with thymic carcinoma (40%) and 4 with thymic carcinoid (5%). Nineteen patients (24%) were treated non-surgically (NS) and underwent definitive radiotherapy or chemoradiotherapy alone, 22 (28%) patients had surgical EO without resection, and 37 (47%) patients had surgical exploration with IR. Among patients who underwent exploration (EO and IR), the most common intraoperative finding precluding complete macroscopic resection was invasion of the great vessels or myocardium (n=41/59, 69%), and extent of pleural or pulmonary metastasis (n=12/59, 20%). Fifty-two patients (67%) developed progression, while 24 patients (31%) had stable disease during the study period. Two patients were lost to follow-up. Patients with thymoma had significantly longer overall survival (OS, P=0.01) compared to those with thymic carcinoma. The median OS for patients with thymoma was 7.7 years whereas the median OS for patients with thymic carcinoma was 4.6 years. There was no significant difference in OS (P=0.40) or progression-free survival (PFS, P=0.20) between IR and NS/EO patients. The median OS for IR patients was 6.0 years and 6.9 years for NS/EO patients.
Conclusions: Despite being unresectable or inoperable, patients with advanced thymic malignancies exhibited long-term survival regardless of the primary treatment modality. In our series, patients who underwent incomplete surgical resections did not appear to fare any better than patients who underwent EO or non-operative treatment.
Keywords: Unresectable; outcomes; thymoma; thymic carcinoma
