Patterns of Care and Outcomes of Patients with Small Gastrointestinal Stromal Tumors at a High-Volume Sarcoma Center.

BACKGROUND: The course of subclinical gastrointestinal stromal tumors (GISTs) is variable. The management of small GISTs is not well-defined. METHODS: Records of patients presenting with small GISTs with documented follow-up appointment at our institution between 2016 and 2022 were identified and reviewed. Comparative univariate analysis to compare patient and tumor characteristics and outcomes was performed. RESULTS: Eighty-six patients were followed for a median of 3.7 years (range 0.1-20 years). The median size at presentation was 1.7 (range 0.1-2.5) cm. A total of 51.2% (n = 44) underwent surgery before or immediately after initial presentation for pain (18.2%), bleeding (15.9%), or patient preference (6.8%). Another 17.4% (n = 15) had delayed surgery for tumor growth (40%), patient preference (2.7%), bleeding (6.7%), or pain (6.7%). The remaining 31.4% (n = 27) of patients never underwent surgery for reasons that included no growth/stability (44.4%), concomitant cancer diagnosis/treatment (29.6%), comorbidities (14.8%), and patient preference (3.7%). Patients who underwent surveillance without intervention compared with those who had delayed surgery were older (71.1 vs. 60.8 years, p < 0.001) with multiple comorbidities or a concurrent cancer diagnosis (70.3% vs. 20%, p = 0.005). There were no differences in survival or rate of distant metastases. Average time to surgery in the delayed group was 2 (range 0.1-10.3) years, and 86% of these patients underwent surgery by 5.5 years after diagnosis. CONCLUSIONS: In older patients with comorbidities or concurrent cancer diagnoses, opting out of surgery does not affect survival. Conversely, younger patients, free from significant comorbidities or other diagnoses, may consider surgery or active surveillance for up to 5 years, with comparable outcomes.

Re-excision After Unplanned Excision of Soft Tissue Sarcoma is Associated with High Morbidity and Limited Pathologic Identification of Residual Disease.

BACKGROUND: Patients with unplanned excision (UPE) of trunk and extremity soft tissue sarcoma (STS) present a significant management challenge for sarcoma specialists. Oncologic re-resection has been considered standard practice after UPE with positive or uncertain margins. A strategy of active surveillance or "watch and wait" has been suggested as a safe alternative to routine re-excision. In this context, the current study sought to evaluate short-term outcomes and morbidity after re-resection to better understand the risks and benefits of this treatment strategy. METHODS: A retrospective, single-institution study reviewed patients undergoing oncologic re-resection after UPE of an STS during a 5-year period (2015-2020), excluding those with evidence of gross residual disease. Short-term clinical outcomes were evaluated together with final pathologic findings. RESULTS: The review identified 67 patients undergoing re-resection after UPE of an STS. Of these 67 patients, 45 (67%) were treated with a combination of external beam radiation therapy (EBRT) and surgery. Plastic surgery was involved for reconstruction in 49 cases (73%). The rate of wound complications after re-resection was 45 % (n = 30), with 15 % (n = 10) of the patients experiencing a major wound complication. Radiation therapy and plastic surgery involvement were independently associated with wound complications. Notably, 45 patients (67%) had no evidence of residual disease in the re-resection specimen, whereas 13 patients (19 %) had microscopic disease, and 9 patients (13%) had indeterminate pathology. CONCLUSION: Given the morbidity of re-resection and limited identification of residual disease, treatment plans and discussions with patients should outline the expected pathologic findings and morbidity of surgery.

Evaluating the Impact of Surveillance Follow-Up Intervals in Patients Following Resection of Primary Well-Differentiated Liposarcoma of the Retroperitoneum.

BACKGROUND: Resection of recurrent retroperitoneal well-differentiated liposarcoma (RP-WDLPS) is unlikely to result in cure. Thus, most clinicians delay surgery after recurrence until symptom intolerance or increasing rate of disease progression. The aim of this study was to determine whether longer surveillance intervals in this population would impact outcomes or delay treatment in those who recur. METHODS: A retrospective review of patients with primary RP-WDLPS who underwent resection between April 1996 and April 2017 and surveillance at MDACC (n = 91) was performed. RESULTS: Median age at diagnosis of primary RP-WDLPS was 61 years; median tumor size was 30 cm. Complete resection was achieved in 85 (93.4%) patients. Among patients who underwent complete resection, recurrence occurred in 53 (60.2%) with median time to recurrence of 27.0 months. Thirty-six (69.6%) of these patients underwent resection of recurrent disease at a median 40.2 months from primary tumor resection. Surveillance imaging at 4-month (vs 3-month) intervals would not have impacted recurrence management in 84 (95.5%) patients; imaging at 6-month (vs 3-month) intervals would not have impacted management of recurrence in 80 (90.9%). CONCLUSIONS: Recurrence was common, often occurring beyond the early postoperative period following primary RP-WDLPS resection. More frequent surveillance imaging (q3-4 vs q6 months) in the first 2 years following primary RP-WDLPS resection may not significantly impact timing of surgery or systemic therapy for recurrence. If longer surveillance intervals were shown to be safe with equivalent outcomes in prospective studies, the resulting change in practice could lead to decreased anxiety and cost for patients and healthcare systems.

Management and outcomes of ruptured, perforated or fistulized tumors of mesenchymal origin.

BACKGROUND: Patients with ruptured, perforated or fistulized (RPF) sarcomas commonly have issues such as sepsis and malnutrition and are usually unsuitable for oncologic resection in the emergency setting. We present our approach for managing a series of patients and the outcomes which were achieved with multidisciplinary care. METHODS: We reviewed records of patients referred to the section of sarcoma surgical oncology. Clinicopathologic factors, preoperative and operative interventions as well as short-term oncologic outcomes were assessed. RESULTS: Sixteen patients were identified between 1 January 1998 to 31 December 2018. Median age was 42.8 years. Histologies were; Gastrointestinal stromal tumors (7), desmoid (4), spindle cell tumor (2), dedifferentiated liposarcoma (2), and nonseminomatous germ cell tumor (1). Five patients had preoperative sepsis, 8 received antimicrobials, and 50% required hospitalization with a median stay of 21 days. Total parenteral nutrition was administered to 5 (31.3%) patients. Median tumor size and estimated blood loss were 13.1 cm and 350 mL respectively. No perioperative mortality occurred. Two patients have expired at a median follow-up of 16.1 months. CONCLUSION: Preoperative optimization, including the use of percutaneous drains, and antibiotics to control sepsis, where necessary, can lead to eventual oncologic resection with acceptable morbidity and no short-term mortality for patients with RPF sarcomas.

Postoperative pancreatic fistula after distal pancreatectomy for non-pancreas retroperitoneal tumor resection.

INTRODUCTION: Short-term outcomes after distal pancreatectomy (DP) for retroperitoneal (RP) tumors are unknown. We sought to identify rates of postoperative pancreatic fistula (POPF) and morbidity after en bloc DP with RP tumor resection. METHODS: A retrospective review of 43 patients who underwent DP with RP tumor resection (1/2011-12/2017) was performed. RESULTS: Seventeen patients had RP sarcoma, 12 renal cell carcinoma, 11 gastrointestinal stromal tumor, and 3 adrenocortical carcinoma. Grade III-IV complications occurred in 7 patients. Grade B POPF occurred in 14 patients, grade C POPF in none, and biochemical leak in 6. Of 22 patients who developed radiographically evident peri-pancreatic fluid collections, 7 required percutaneous drainage. The 90-day readmission rate was 33%. CONCLUSIONS: DP with RP tumor resection is associated with high rates of clinically relevant POPF compared to historical results for DP for primary pancreatic tumors. Multi-center studies to identify targetable predictors and risk mitigation strategies for POPF in this rare high-risk population are needed.