A Case of Mesenteric Desmoid Tumor Causing Bowel Obstruction After Laparoscopic Surgery

Background: A desmoid tumor is a rare neoplasm that is derived from soft tissues. Although it shows benign characteristics pathologically, local recurrence can occur. Case report: We herein report the case of a patient with an intraabdominal desmoid tumor that developed 3 years after laparoscopic appendectomy for acute appendicitis. A 59-year-old male visited our emergency room with complaints of abdominal pain and fullness. Abdominal computed tomography revealed distention of the small intestine with a point of obstruction by an intraabdominal tumor-like region. Pathological findings showed that the tumor was compatible with desmoid fibromatosis. Conclusion: In cases with an intraabdominal tumor after laparoscopic surgery, it is important to consider the possibility of a desmoid tumor, since it is difficult to diagnose it accurately before surgery.

Background: Abdominal fibromatosis presenting as an abdominal mass is a rare occurrence in a gynecological setting. The diagnosis may not be suspected preoperatively and management may be challenging. Case: An 18-year-old girl with ovarian germ-cell malignancy was managed with staging-laparotomy and chemotherapy. She developed a large abdominal mass ten-months later. An abdominopelvic mass (40 × 20cm) was removed at laparotomy. The histopathological diagnosis was intraabdominal fibromatosis. A rapidly growing abdominal mass recurred postoperatively. After discussion with the tumor-board, chemotherapy with methotrexate and vinblastine was started. The tumor was not responsive and the patient succumbed after the second cycle of chemotherapy. Summary and conclusion: Abdominal fibromatosis should be considered among the differential diagnoses of a rapidly growing abdominal mass after resection of an ovarian germ cell tumor.

Background: Abdominal aggressive fibromatosis (AF) can be confounded with abdominal wall endomentriosis (AWE) because they share considerable similarity. Because of the different patient prognoses and treatment strategies available, accurate pre-operative diagnosis is important. Case Presentation: We here report two cases of abdominal masses presenting as periodic changes in tumor sizes, which occurred in correlation with the menstrual cycle. The clinical findings were highly suggestive of AWE. However, the final pathological findings revealed AF. The estrogen receptor and progesterone receptor expressions were negative in the two cases. The differences between the two diseases have been discussed in detail. Conclusion: A diagnosis of AWE should be scrutinized closely if the patient does not complain of cyclic pain. Fine-needle aspiration cytology is a suitable tool for pre-operative evaluation.

Xentuzumab is an insulin-like growth factor (IGF) ligand-neutralizing antibody. This phase 1 trial assessed xentuzumab in Japanese patients with solid tumors. Patients aged ?20 years old with solid tumors that were refractory or not amenable to standard therapy were enrolled. Patients received xentuzumab intravenously at a starting dose of 750 mg/week. Dose escalation used a 3+3 design with dose de-escalation. The primary endpoint was to determine the maximum tolerated dose (MTD) of xentuzumab. Safety, pharmacokinetics, pharmacodynamics and anti-tumor activity were also assessed. Fifteen patients received xentuzumab in the dose escalation part (750 mg/week [n = 6]; 1000 mg/week [n = 3]; 1400 mg/week [n = 6]). There were no dose-limiting toxicities at any dose; MTD of xentuzumab was not reached. Xentuzumab 1000 mg/week was recommended as the relevant biological dose. Six further patients received xentuzumab 1000 mg/week in an expansion cohort. Of 21 patients, 13 (61.9%) experienced a drug-related adverse event, most commonly fatigue (23.8%), neutropenia (19.0%), diarrhea, nausea, white blood cell count decreased, and muscle spasms (14.3% each). No relevant deviations from dose linearity of xentuzumab exposure were observed during dose escalation. Total IGF-1 and IGF-2 levels increased, and bioactive IGF levels decreased, from baseline to 24 hours after the first infusion in cycle 1. Partial response was observed in two (9.5%) patients with desmoid-type fibromatosis. Disease control was achieved in six (28.6%) patients (median duration 42.4 months). Xentuzumab monotherapy was well tolerated in Japanese patients and showed evidence of anti-tumor activity.

Desmoid tumors most commonly occur in the anterior abdominal wall in approximately 50% of cases and are locally aggressive. We describe a case of a 38-year-old lady who was investigated as a case of gastrointestinal tumor. Post-operative immunohistochemistry staining showed the presence of a synchronous desmoid in the abdominal wall and proximal ileum. Wide local excision remains the gold-standard of treatment with pharmacotherapeutics and radiotherapy serving as adjuvant or palliative treatment options.

Desmoid fibromatosis (DF) involving the gastrointestinal tract is extremely rare. Its intramural location and occasional expansile growth pattern within the bowel wall may mimic a gastrointestinal stromal tumor (GIST). Due to the different disease behaviors and management, it is important to make a correct diagnosis before further treatment. We present an extremely rare case of a gastric DF that on imaging appeared as a discrete intramural mass mimicking a GIST and that was preoperatively correctly diagnosed as a DF based on its cytomorphologic, immunohistochemical, and molecular profiles. The patient is a 71-year-old female who presented with dysphagia and unintentional weight loss. A mass was identified at the gastric fundus. Endoscopic ultrasound-guided fine-needle aspirate (FNA) and biopsy (FNB) were performed. The FNA showed a few small aggregates of cytologically bland spindle-shaped cells with elongated nuclei. The FNB yielded small fragments of tissue composed of bland spindle cells demonstrating nuclear and cytoplasmic immunostain for ?-catenin and focal stain for smooth muscle actin (SMA) and desmin. CD117, DOG1, CD34, caldesmon, S100, cytokeratin AE1/AE3, signal transducer and activator of transcription 6 (STAT6), MUC4, progesterone receptor (PR), and anaplastic lymphoma kinase (ALK) were negative, and MIB-1 showed a very low proliferation activity index. Molecular studies performed by targeted next-generation sequencing showed activating mutations in CTNNB1. These results excluded a GIST and confirmed the diagnosis of a gastric DF. Although it is very rare, DF must be included in the differential diagnosis of discrete intramural gastric spindle cell lesions. A definitive diagnosis can be made preoperatively if enough lesional material is available for appropriate immunohistochemical and molecular studies.