Postoperative thoracic paraspinal desmoid tumor: illustrative case.

BACKGROUND: Desmoid-type fibromatosis is a rare soft tissue tumor characterized by invasive growth within deep connective tissue without metastasis. The etiology is largely unknown, but several cases have been reported in the postoperative setting. The management is multidisciplinary and largely dependent on individual presentation. Here the authors report a postoperative case of a rapidly progressive and symptomatic paraspinal desmoid tumor (DT). ^p OBSERVATIONS: A 51-year-old female with a history of familial adenomatous polyposis and a previous L3-5 decompressive laminectomy and fusion presented to the neurosurgery clinic with complaints of a painful left posterior flank mass. Imaging disclosed a left posterior thoracic soft tissue mass originating at the T8-9 level and extending through the T11-12 level, suggestive of sarcoma. Pathological analysis from an open biopsy specimen confirmed desmoid-type fibromatosis. The patient underwent total resection. At 5 months postoperatively, she reported a progressive resolution of her symptoms without recurrence. ^p LESSONS: Paraspinal DTs are a rare occurrence that may be de novo in origin or arise following spinal surgery. These tumors have a predilection for middle-aged females and may present in any region of the spine. A biopsy is needed for definitive diagnosis. Management may be active surveillance, medical management, or surgical management. https://thejns.org/doi/10.3171/CASE25573.

In the phase III placebo-controlled DeFi trial (ClinicalTrials.gov identifier: NCT03785964) primary analysis, nirogacestat showed significant improvement versus placebo in progression-free survival (PFS), objective response rate (ORR), and patient-reported outcomes (PRO) in adult patients with progressing desmoid tumors (DT; median [range] exposure: 20.6 [0.3-33.6] months). Here, long-term nirogacestat efficacy and safety were evaluated in patients randomly assigned to nirogacestat and followed through the final data cutoff date of December 19, 2024. End points included PFS and ORR per RECIST v1.1, PRO, and safety. The median (range) duration of exposure was 33.6 (0.3-61.8) months. Median PFS was not reached. The ORR with up to 4 years of nirogacestat treatment was 45.7% (32 of 70), with three additional partial and three additional complete responses since the primary analysis. Further target tumor size reduction occurred in most patients. Benefits in PROs were sustained while on treatment. Frequently reported treatment-emergent adverse events (TEAEs) decreased in incidence and severity over time. Since the primary analysis, four patients discontinued nirogacestat because of TEAEs between years 2 and 4. In conclusion, long-term continuous nirogacestat treatment was associated with further tumor size reductions, durable objective responses, sustained PRO benefits, and a manageable safety profile consistent with the primary analysis.

Primary mesenteric tumors (PMTs) are rare, often presenting asymptomatically until large enough to compress adjacent structures. We present a case of a 36-year-old female with atypical post-cesarean abdominal pain. Imaging revealed an 11 × 10 cm mesenteric mass suggestive of sarcoma or desmoid tumor. Surgical exploration identified a mass involving the mesentery and ileum, necessitating resection of both, along with venous reconstruction of the superior mesenteric vein using a cadaveric graft. A postoperative complication due to venous stasis required a second operation with right colectomy and jejuno-transverse anastomosis. Final pathology confirmed desmoid-type mesenteric fibromatosis. The patient recovered well and remains disease-free and asymptomatic 12 months postoperatively. This case highlights the diagnostic and therapeutic challenges of PMTs, the importance of surgical expertise in vascular reconstruction, and the need for individualized treatment planning to achieve complete tumor resection while minimizing complications such as short bowel syndrome.

Desmoid tumor is a rare locally progressive tumor represented by fibroblasts. Unlike other malignancies, desmoids do not metastasize. However, they can cause serious problems due to local spread. These neoplasms can have different localization, but are most often diagnosed in anterior abdominal wall. Desmoids can pose specific clinical challenges for surgeons and patients. This disease is extremely rare. Thus, there are few randomized studies devoted to effectiveness of each treatment method. This circumstance necessitates further research in these patients to assess the effectiveness of treatment. The authors describe a patient with large desmoid fibroma of anterior abdominal wall. This clinical case represents a unique opportunity to analyze the features of diagnosis and treatment of desmoid tumor. This material will be especially useful for abdominal surgeons, oncologists and morphologists. [article is in russian]

INTRODUCTION AND IMPORTANCE: Desmoid-type fibromatosis (DF) is a rare, benign fibroblastic tumor arising from musculoaponeurotic structures. Despite lacking metastatic potential, it can be locally aggressive. Retroperitoneal DF is uncommon, and its presentation with obstructive jaundice is extremely rare. n CASE PRESENTATION: A 55-year-old male with no significant medical or family history presented with a six-month history of right upper quadrant abdominal pain and three weeks of progressive jaundice. Laboratory findings revealed a cholestatic pattern and elevated CA 19-9. Imaging, histopathological examination and immunohistochemistry were consistent with desmoid-type fibromatosis. The patient was managed with palliative chemotherapy and percutaneous transhepatic biliary drainage (PTBD) to relieve biliary obstruction. n CLINICAL DISCUSSION: Retroperitoneal DF is typically managed with surgical excision or watchful waiting, depending on the location and symptoms. While surgical resection is preferred, it is often not feasible in cases involving extensive invasion. In this case, chemotherapy served as the primary treatment modality due to the tumor’s unresectability. n CONCLUSION: This case highlights the importance of including retroperitoneal desmoid-type fibromatosis in the differential diagnosis of obstructive jaundice and underscores the need for larger studies and updated management guidelines.

Desmoid tumors (DTs), also known as aggressive fibromatosis, are rare neoplasms characterized by local invasiveness and a high risk of recurrence, despite their lack of metastatic potential. The management of these tumors remains challenging due to their unpredictable behavior and heterogeneous presentations. In this two-part study, we first provide a comprehensive review of the scientific evidence on diagnosis and emerging therapeutic strategies for DT. In the second part, we will present a retrospective analysis of our experience at a national reference center for sarcoma treatment, focusing on diagnostic strategies, therapeutic interventions, and clinical outcomes.