The histologic outcomes of indeterminate thyroid nodules with rat sarcoma mutations: A case series.

Molecular testing is an adjunct test for thyroid fine needle aspirations with indeterminate diagnoses, with certain mutations showing a greater risk of malignancy (ROM). Rat sarcoma (RAS) point mutations are the most common alterations in indeterminate thyroid nodules. While they can have a high ROM, they are also found in benign disease. This study describes the histologic outcomes of indeterminate nodules with RAS mutations. Bethesda III and IV thyroid nodules with ThyroSeq results showing RAS mutations (NRAS, KRAS, and HRAS) were identified between November 1, 2018 and February 28, 2023. Baseline patient characteristics, ThyroSeq results, and surgical diagnoses were collected. We identified 18 nodules with RAS mutations from 17 patients. Fourteen were NRAS (isolated NRAS in 6; NRAS with other abnormalities [NRAS+] in 8); one was isolated KRAS; and three were HRAS with other abnormalities (HRAS+). NRAS Q16R was the most common amino acid change. Twelve cases had follow-up. Two were malignant, a minimally invasive follicular carcinoma (NRAS+) and a papillary thyroid carcinoma, follicular variant (HRAS+). Three were noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP), 2 HRAS+ and 1 NRAS+. Four were follicular adenomas, one being atypical (3 NRAS+ and one isolated NRAS). One was an oncocytic adenoma (isolated NRAS). Two were nodular hyperplasias (isolated NRAS and NRAS+, respectively). Twenty-eight percent of our RAS-mutated nodules were malignant or NIFTP. All three HRAS-mutated nodules were malignant or NIFTP. The three isolated RAS mutations with follow up were benign (adenomas or nodular hyperplasia). These findings were in line with the literature.

Cyst of Hattori: A Rare Cyst in the Posterior Mediastinum.

Sixteen years since their initial description in the literature, posterior mediastinal Mullerian cysts - otherwise known as cysts of Hattori, after their discoverer - remain rare, with only 40 patients reported as of 2020. We report a 43 year old obese female that presented with a 2.6 cm cyst found in the posterior mediastinum by endoscopic ultrasound (EUS) and previously by chest magnetic resonance imaging (MRI) originally diagnosed as a congenital enteric duplication cyst of the esophagus radiologically. Upon surgical excision via a DaVinci thoracoscopy, the cyst was confirmed to be of Mullerian origin by PAX8, WT1, and ER staining. It is possible that the majority of cysts of Hattori remain unrecognized and undiagnosed, given their rarity and resemblance to other pathologies. It is important that this entity become a part of every pathologist's differential for a posterior mediastinal cyst in a female.

Cytologic analysis of a glomus tumor in the left second toe: Case report.

We present a 66-year-old female with a glomus tumor diagnosed by fine-needle aspiration (FNA) at the subungual region of her left second toe. Cytologic findings include cohesive clusters of round, uniform cells with scant cytoplasm. Nuclei were monotonous with fine chromatin. No cellular atypia, nuclear inclusions, mitotic figures, nor nucleoli were identified. Cells were surrounded by thick wisps of magenta colored myxoid material reminiscent of a pleomorphic adenoma. Few spindle shaped cells could be seen near the border of the tumor clusters. Staining was positive for alpha-smooth muscle actin. This case report presents one of few FNA diagnosed glomus tumors.

Laparoscopic Right Hemicolectomy to Curatively Treat Primary Leiomyosarcoma at the Ileocecal Valve.

Primary leiomyosarcomas of the colon (PLC) are rare tumors, representing 0.12% of all colon malignancies. We report a 59-year-old man with weight loss, mild anemia, and rectal bleeding. Colonoscopy revealed a 3.2 × 2.6-cm mass at the ileocecal valve. Histopathological examination of the biopsy showed a spindle cell neoplasm that stained positive for smooth muscle actin, caldesmon, and desmin. A diagnosis of PLC was made. Subsequently, a laparoscopic right hemicolectomy was performed, and no local recurrence was noted 6 months after the resection. Given the rarity of PLC, more studies on the clinical features and treatments of this tumor are warranted.

Metastatic pheochromocytoma to the pancreas diagnosed by endoscopic ultrasound-guided fine needle aspiration: A case report and review of literature.

Pancreatic pheochromocytomas are rare and typically diagnosed by local resection. We present the first reported case of metastatic pheochromocytoma to the pancreas diagnosed by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and cytology. A 67-year-old female presented with 2 to 3 months of abdominal pain. A CT scan showed a large mass in the head of the pancreas engulfing the superior mesentery artery and vein, along with a large mass in the left adrenal gland. An EUS-FNA was performed on the pancreatic mass with a 22-gauge needle, yielding an adequate sample. Papanicolaou stain, Diff-Quik, and cell block showed loosely cohesive clustered tumor cells and singly dispersed pleomorphic naked tumor nuclei with anisonucleosis and cytoplasmic vacuolization. Tumor cells stained positive for synaptophysin, chromogranin A, and CD56 and negative for CK AE1/3 and CK AE1/3-CAM5.2 cytokeratin cocktail. Because of cytokeratin negativity, diffusely positive neuroendocrine markers, and the presence of an adrenal mass, a metastatic malignant pheochromocytoma was suspected. Additional testing showed elevations in plasma metanephrines and normetanephrines, urine metanephrine-to-creatinine and normetanephrine-to-creatinine ratios, and serum chromogranin A. An iodine123 -metaiodobenzylguanidine (MIBG) scan was obtained, which showed significantly increased MIBG uptake in the left adrenal lesion. A diagnosis of metastatic malignant pheochromocytoma was made. Surgical oncology was consulted, who recommended against resection of the adrenal mass in favor of outpatient management. Metastatic pheochromocytoma to the pancreas are rare tumors that may yield diagnostic material by EUS-FNA with a 22-gauge needle.

Primary pancreatic leiomyosarcoma with metastasis to the liver diagnosed by endoscopic ultrasound-guided fine needle aspiration and fine needle biopsy: A Case Report and Review of Literature.

Primary pancreatic leiomyosarcomas are rare tumors of the pancreas that are usually diagnosed after resection or by biopsy. One case in the literature has utilized endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) cytology. We report a second case of a primary pancreatic leiomyosarcoma that yielded diagnostic material on EUS-FNA cytology. A 72-year-old female presented with 3-4 months of abdominal pain. A CT scan showed a large heterogeneous, lobulated pancreatic head and uncinate mass and multiple hypoattenuating liver lesions. An EUS-FNA was performed on one of the liver lesions with a 25-gauge needle, yielding an adequate sample with lesional cells. The initial read was a spindle cell neoplasm. A subsequent endoscopic ultrasound-guided fine needle biopsy with a 22-gauge needle was performed on the pancreatic head mass to rule out two primaries and to provide tissue for a mitotic index in the case of gastrointestinal tumor. Both the cell block of the EUS-FNA and the core biopsy were equally cellular and showed interlacing spindle cells that stained positive for SMA and negative for DOG-1, CD 117, and CD34. In addition, the core biopsy of the pancreas stained positive for Desmin. A diagnosis of a primary pancreatic leiomyosarcoma was made and the patient was started on systemic chemotherapy. Primary pancreatic leiomyosarcomas are rare pancreatic tumors that may yield diagnostic material by EUS-FNA with a 25-gauge needle. Diagn. Cytopathol. 2016;44:1070-1073. © 2016 Wiley Periodicals, Inc.

A phacoemulsification chopping technique that attacks the posterior plate

Surgical Technique: The technique involves creating a central crater, flipping the nucleus out into the supracapsular space, and creating another crater through the posterior surface that will eventually connect with the anterior crater to produce a central hole. The donut-shaped nucleus is then chopped and the fragments are aspirated with greater ease. Results: The technique was performed successfully in seven eyes of six patients with only minor problems. Phacoemulsification times were longer than usual because of the additional sculpting, but clinical results were not adversely affected. Conclusion: For dense or hard cataracts for which the surgeon anticipates a tough posterior plate, this technique is a safe alternative to the usual chopping techniques.