10 Years' Experience of Transplant Oncology in the Management of Unresectable Desmoid Tumor: One-staged or Two-staged Approach

Background: There has been a growing interest in Transplant Oncology to achieve maximal debulking of neoplasms not amenable to conventional surgical resection. However, the surgical strategy and timing of desmoid tumor resection using visceral transplantation (VTx) remains controversial. Methods: Retrospective chart review identified 25 patients who received radical resection of mesenteric and pelvic desmoid tumor in our intestinal transplant program for the last 10 years. Surgical strategy was classified into three groups: 1) no VTx group with aggressive tumor resection, 2) one-staged tumor removal at time of VTx, and 3) two-staged approach with an initial debulking surgery followed by VTx as a second stage. Surgical strategy was determined with the following factors: salvageability of intestine, growth rate of tumors, tumor proximity to pancreas and duodenum, Spigelman classification of duodenal polyposis, ureter involvement, and transplant candidacy. For one-staged VTx, to minimize cold ischemic time, recipient surgery was started before donor operation, anticipating a good quality of organ. Only perfect donors were accepted for this setting. Results: The mean age of patients was 37.5 years (range 21-68) with 72 % male. The median time from diagnosis to referral was 12 years and number of previous surgeries was 3 (range 2-10). enterocutaneous fistulae and ureteric involvement were present in 9 (36%) and 12 patients (48%), respectively. Without preparing VTx, 14 patients underwent radical tumor resection with ureteric reconstruction in 7 patients with lengthy operative time of 11 hours. Six of the 14 (43%) developed tumor recurrence and required further resections. One-staged VTx was performed in 4 patients using isolated intestinal grafts. The tumors were in central mesentery without involvement of retroperitoneum/pelvic structures or upper abdominal organs. Cold ischemic time was managed in the range of 3-5.9 hours despite challenging tumor dissection. Two-staged VTx was done in 7 patients and associated with more organs’ involvement that required lengthy debulking in the initial surgery and required full- or modified multivisceral organ replacement at the second stage. Waiting time for organ was significantly longer in two-staged group compared to one-staged group (240 days vs 17 days, p<0.01). Tumor recurrence after transplant was limited to 2 patients and didn’t affect the patient’s survival. Four patients died after full-or modified MVTx due to infection, PTLD or GVHD. Intention-to-treat survival in the entire cohort was 77% at 5 years. No VTx group and one-staged group had an excellent 2-year survival of 90 % and 100 %, respectively. Conclusions: Radical resection of unresectable mesenteric tumor can be done with organ replacement with favorable outcome for cases with lower tumor burden. Two-staged VTx remains a valid option for patients who have high tumor burden and no other alternatives.