Yoshihiro Ohishi

Fibrin-associated large B cell lymphoma is a rare Epstein–Barr virus-positive lymphoma arising in restricted anatomical spaces, predominantly in immunocompetent individuals; its clinical behavior and pathophysiology remain unclear. We report two cases of fibrin-associated large B cell lymphoma that were incidentally detected in bulky uterine leiomyomas and ovarian fibromas. The first patient presented with limited-stage disease and showed an indolent clinical course, managed with surgery alone; the second presented with advanced-stage disease with malignant pleural effusion, requiring chemotherapy. Lymphoma cells in the pleural effusion shared an immunohistochemical staining profile with the primary site, and genomic analysis confirmed B cell clonality. Both patients shared an unusual Epstein–Barr virus latency pattern, possibly reflecting a locally immunosuppressed microenvironment. These cases broaden the recognized spectrum of fibrin-associated large B cell lymphoma and highlight that, although typically localized, the disease may present with concomitant involvement of multiple sites at diagnosis.

Objective: Gastrointestinal stromal tumors (GISTs) are often reported to coexist with other malignancies, mainly on the basis of postoperative pathological studies for GISTs or other malignancies. This preliminary study aimed to examine the preoperative clinical prevalence of synchronous malignancies and patient and tumoral features in patients with gastric GISTs preoperatively diagnosed using endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). Materials and Methods: 184 patients with gastric GIST diagnosed using preoperative EUS-FNA and postoperative histopathology were analyzed in this retrospective single-center observational study. Staging and assessment for synchronous malignancies was performed using preoperative esophagogastroduodenoscopy (EGD), total colonoscopy (TCS), and computed tomography (CT) of the chest, abdomen, and pelvis. Results: Ten gastric GIST patients had a single synchronous malignancy and two patients harbored two. Two of the 184 patients who underwent EGD exhibited synchronous upper gastrointestinal (GI) malignancy on EGD (1.1%): gastric intramucosal adenocarcinoma in one and superficial esophageal squamous cell carcinoma in the other. Five of the 150 patients who underwent TCS exhibited synchronous lower GI malignancy (3.3%): colorectal adenocarcinoma in three and submucosal carcinoid tumor in two. Extra-GI malignancy was found in a variety of organs in seven of 172 patients who underwent CT (4.1%). Patients with a synchronous malignancy were significantly older than those without (p = 0.02). Conclusion: Preoperative synchronous malignancy is relatively common in patients diagnosed with gastric GIST using EUS-FNA. Preoperative EGD, TCS, and CT of the chest to pelvis are desirable in these patients to assess for synchronous malignancies, as it may affect the treatment plan.

Background/Aims: The efficacy and safety of endoscopic submucosal dissection using a clutch cutter (ESD-CC) for subepithelial lesions within the esophagogastric submucosa (SELEGSM) has not been investigated. This study aimed to assess the efficacy and safety of ESD-CC for the treatment of SELEGSM.Methods: This prospective study included 15 consecutive patients with 18 SELEGSMs diagnosed by endoscopic ultrasonography. The primary outcomes were short-term outcomes including en bloc resection rate, R0 resection rate, procedure time, and complication rate. The secondary outcome was final histological diagnosis.Results: Among the participants, 18 lesions were identified: 12 in the stomach (nine patients) and six in the esophagus (six patients). The en bloc resection rate was 94.4% (17/18). The R0 resection rate was 88.9% (16/18). The median operating time was 39 min, and no instances of perforation or bleeding were observed. The final diagnoses of SELEGSM included six neuroendocrine tumors (33.3%), six granular cell tumors (33.3%), two ectopic pancreases (11.1%), one inflammatory fibroid polyp (5.6%), one leiomyoma (5.6%), one lipoma (5.6%), and one leiomyosarcoma (5.6%).Conclusions: ESD-CC appears to be a technically efficient and safe approach for SELEGSM resection, suggesting its potential as a valuable treatment option.

Background/Aims: For duodenal subepithelial lesions showing a hypoechoic mass on endoscopic ultrasound imaging, the utility of endoscopic ultrasound-guided fine-needle aspiration and the frequency of histological types have not been the focus of previous literature. This study aimed to clarify this. Materials and Methods: This prospective observational study enrolled 22 consecutive patients who underwent endoscopic ultrasoundguided fine-needle aspiration for duodenal subepithelial lesions with hypoechoic mass on endoscopic ultrasound. Immunohistochemical analysis was performed for all endoscopic ultrasound-guided fine-needle aspiration and surgically resected specimens. The main outcome measures were the technical results of endoscopic ultrasound-guided fine-needle aspiration and the frequency of histological types of duodenal subepithelial lesions with hypoechoic mass. Results: Thirteen fine-needle aspiration specimens were obtained from the duodenal bulb and eight from the descending duodenal region. The puncture was not performed because of intervening vessels in one patient. The diagnostic rate was 81% (95% confidence interval: 58.1-94.6, 17/21 patients). In 12 patients receiving surgical resection (excluding one cancellation of endoscopic ultrasoundguided fine-needle aspiration), the diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration was 75% (95% confidence interval: 42.8-94.5, 9/12 patients). No complications were observed. The histopathological diagnoses included 11 cases of gastrointestinal stromal tumor (50%), 2 cases of leiomyoma (9%), 2 cases of metastatic cancer (9%), 2 cases of benign inconclusive, and 1 case each of carcinoid, malignant lymphoma, leiomyosarcoma, gauzeoma, and aberrant pancreas (4.5% each). The frequency of malignant tumors in the duodenal subepithelial lesions with hypoechoic mass group was 73% (16/22 patients). Conclusions: Endoscopic ultrasound-guided fine-needle aspiration for duodenal subepithelial lesions with hypoechoic mass was safe and accurate. As duodenal subepithelial lesion with hypoechoic mass has a reasonably high possibility of containing malignant tumors, it is desirable to perform endoscopic ultrasound-guided fine-needle aspiration. Cite this article as: Akahoshi K, Akahoshi K, Shiratsuchi Y, et al. Endoscopic ultrasonography-guided fine-needle aspiration for duodenal subepithelial lesions showing a hypoechoic mass on endoscopic ultrasound imaging. Turk J Gastroenterol. 2023;34(11):1156-1162.