Understanding and Overcoming the Pitfalls in Cytopathological Diagnosis of Hyalinizing Trabecular Tumor of Thyroid.

Hyalinizing trabecular tumor (HTT), a rare low-malignant-potential thyroid neoplasm, is usually treated with conservative surgery. However, cytomorphological diagnosis of HTT is challenging due to the significant overlap of nuclear features with more common malignancies such as papillary thyroid carcinoma (PTC), which usually requires more radical surgical intervention. To avoid unnecessary overtreatment, a precise diagnosis of HTT is therefore essential. Advances in molecular diagnostics provide the opportunity to overcome the limitations of cytological analysis. We present a case of HTT in a 71-year-old male who was initially suspected to be PTC based on cytopathology. However, further molecular analysis revealed PAX8::GLIS3 gene fusion, classifying the lesion as HTT and preventing surgical overtreatment. We discuss the diagnostic pitfall of cytopathology in HTT and suggest using emerging molecular genetic tools to avoid it.

A 65-Year-Old Male With Classic Cardiac Sarcoidosis: Case Report and Review of the Literature.

Sarcoidosis is a systemic disease characterized by the formation of non-necrotizing granulomas, primarily involving the lungs and other organs such as the heart. The diagnosis of cardiac sarcoidosis can be difficult. The last set of diagnostic guidelines for diagnosis and treatment of cardiac sarcoidosis was published in 2019 by the Japanese Circulation Society (JCS). We describe a case of classic cardiac sarcoidosis and review the literature on clinical presentation, imaging, and management.

Adjuvant I-131 therapy for T0-3 N1b M0 differentiated thyroid cancer with many (≥ 5) positive nodes.

Background: In patients with well-differentiated thyroid cancer, there is controversy about the prognostic importance of a large number of positive neck nodes and the potential value of radioiodine therapy. The purpose of this study was to evaluate this issue in the group of patients for whom it is most clinically important - those with classic histology and favorable T and M stage. Materials and methods: Twenty-five patients met the following inclusion criteria: classic histology of papillary or follicular thyroid carcinoma treated with total thyroidectomy and neck dissection followed by adjuvant I-131 treatment in our department between January 1, 2003, and December 31, 2013; adult age of > 21 years; and American Joint Committee on Cancer (AJCC ) stage (8th edition) of T0-3, N1b with ≥ 5 positive nodes, and M0. Results: The median positive node number was 10 (range, 5-31). The median adjuvant I-131 dose was 158 mCi (range, 150-219 mCi). The median follow-up in patients without recurrence after treatment was 7.3 years. The 10-year actuarial rates were favorable: overall survival, 100%; freedom from visible recurrence, 82%; and visible or biochemical recurrence, 72%. Conclusion: Recurrence was infrequent in our study population with ≥ 5 positive nodes following moderate-dose adjuvant I-131 treatment. These results are valuable in directing initial adjuvant therapy and follow-up intensity. Our results do not inform the question of the use of postoperative thyroglobulin (Tg) level to select N1b patients for low-dose I-131 treatment.

Secretory Carcinoma of the Oral Cavity: A Retrospective Case Series with Review of Literature.

Secretory carcinoma (SC) is an uncommon salivary gland neoplasm of the oral cavity that microscopically may mimic acinic cell carcinoma (ACC) and mucoepidermoid carcinoma (MEC). This study describes a series of SC in minor glands with a literature review. We performed a retrospective search for oral SC, within the archives of the University of Florida, Oral Pathology and Surgical Pathology Biopsy services from 2010 to 2018. A total of 10 SCs were identified in the oral and maxillofacial region, four of which were in the minor salivary glands. The demographic, clinical, histological, and molecular findings were aggregated for all 4 cases. Patient age varied from 30 to 60 years, with an average of 45 years. Two cases each were in female and male patients. Two cases presented on the labial mucosa, and one each on the hard and soft palate. Immunohistochemical (IHC) staining showed mammaglobin positivity in all cases, GATA3 positivity in two cases, S100 positivity in three cases, and SOX10 positivity in only one case. Fluorescence in situ hybridization demonstrated positivity for ETV6-NTRK3 fusion in 4 cases. Although oral SC is rare, pathologists should be aware of the histologic overlap between the SC and other salivary gland neoplasms such as ACC and MEC. A judicious application of IHC staining would aid in diagnosis. SC should be considered in the differential diagnosis for intraoral salivary gland tumors.

Primary cardiac low-grade neuroendocrine tumor: a case report and review of the literature.

Primary tumors of the heart are uncommon; even rarer are primary cardiac neuroendocrine tumors. To our knowledge, only two cases have been described to date, both being high-grade tumors. We report a solitary low-grade neuroendocrine tumor of the heart, unexpectedly discovered during aortic valve repair for infectious bacterial endocarditis on the wall of the right ventricle in a 44-year-old man with a history of balloon valvulotomy as a child. Frozen section was sent intraoperatively and demonstrated a plasmacytoid neoplasm. Final pathology of the biopsies showed a tumor composed of both cohesive and discohesive plasmacytoid cells separated by a vascular network and strands of fibrosis. The tumor showed strong reactivity for AE1/3, synaptophysin, and CDX2 with focal reactivity for chromogranin-A and CD56. Neither necrosis nor a mitotic rate of greater than 2 mitoses per 2 mm2 was seen. A colonoscopy was performed and demonstrated only a tubular adenoma. An esophagogastroduodenoscopy was unremarkable. PET-CT DOTATATE, performed after complete resection of the tumor, demonstrated no abnormal radiotracer uptake. The patient continues to do well at present, 1 year later, and reports no symptoms attributable to carcinoid syndrome or disease progression. The patient was assigned by medical oncology to yearly follow-up and imaging, and is considered to have no evidence of disease.

Carcinosarcoma Arising from Inverted Papilloma in a Patient with History of Radiotherapy for Sinonasal Squamous Cell Carcinoma.

BACKGROUND Carcinosarcoma of the sinonasal tract is an extremely rare malignant neoplasm; it is often designated as carcinoma with spindle cell or sarcomatoid features. We report a case of carcinosarcoma arising in a pre-existing inverted Schneiderian papilloma in the left maxillary antrum and nasal cavity of a 72-year old male patient. CASE REPORT The patient had a significant history of radiotherapy for squamous cell carcinoma in the sinonasal area, 3 decades ago. The patient presented with chief complaints of left nasal blockage, nasal discharge, anosmia, and occasional epistaxis. Computed tomography scan displayed a lobular soft tissue mass resulting in narrowing of the nasopharyngeal airway with massive destruction of palatal tissue. The lesion was resected via endoscopic surgery. Macroscopically, a white fleshy appearance with necrosis was noted in the submitted specimen. Microscopically, the tumor was composed of pleomorphic epithelial and spindle cells with numerous mitoses and remarkable tissue necrosis. Residual inverted papilloma (IP) with high-grade dysplasia, and minimal foci of moderately differentiated squamous cell carcinoma (SCC) component was present at the tumor margin. A distinct zone of transition of SCC to spindle cell carcinoma (SpSCC) was noted and confirmed by focal positivity of p63 in epithelial and sacromatoid components. The pleomorphic sarcomatoid tumor was positive for vimentin with Ki67 highlighting 70% of tumor cells. A final diagnosis of sinonasal spindle cell carcinoma associated with residual inverted papilloma was rendered. CONCLUSIONS Due to the rarity of such cases, the prognosis and response to treatment is unclear. No effective directed treatment has been developed. Unfortunately, the patient refused any further treatment and died of persistent disease. To the best of our knowledge, only one case of sinonasal carcinosarcoma arising from dysplastic inverted papilloma has been reported. The distinct possibility of previous radiotherapy contributing to development of sarcomatoid features in this neoplasm should also be considered.

p16INK4a as a proliferation marker unrelated to HPV expression in odontogenic cysts and tumors.

INTRODUCTION: p16INK4a is a tumor suppressor protein that retards cell cycle progression from G1 to S phase. Prior studies have evaluated p16INK4a expression in odontogenic keratocyst and ameloblastoma, but data regarding other odontogenic cysts and tumors have been sparse. METHODS: With IRB approval, cases from the following entities were identified from archives of the UF Oral Pathology Biopsy Service (2005-2015): benign incidental odontogenic rest, dentigerous cyst, lateral periodontal cyst, calcifying odontogenic cyst, glandular odontogenic cyst, odontogenic keratocyst, orthokeratinized odontogenic cyst, adenomatoid odontogenic tumor, calcifying epithelial odontogenic tumor, and ameloblastoma. All cases were submitted for p16INK4a immunohistochemical testing. RESULTS: Results were scored as follows: nuclear and cytoplasmic staining of <5% cells (score 0), 5%-25% (score 1), 25%-50% (score 2), >50% (score 3). No significant difference in p16INK4a staining was noted between odontogenic cysts and the listed odontogenic tumors (chi-square, P = .540). When comparing lesions with higher recurrence rates (over 25% as reported in the literature) versus lesions with low recurrence rates (under 25%), higher recurrence correlated to significantly higher p16INK4a positivity (chi-square, P = .001). Follow-up testing was performed on 18 cases with "2" or "3" p16INK4a expression scores for high-risk HPV strains through HPV in situ hybridization (ISH) messenger RNA testing with no cases exhibiting a positive result. CONCLUSION: This study exhibits an association between increased p16INK4a positivity and odontogenic lesions with higher recurrence rates and highlights the role of p16INK4a as a progression marker unrelated to HPV expression in this group of pathologic entities.

Cancer Genes Mutations in Benign Metastasizing Leiomyoma: A Case Report.

Benign metastasizing leiomyoma is a very uncommon clinicopathologic entity with unknown molecular pathogenesis. We present a case of a 40-year-old woman who has a history of surgical resection of a large uterine leiomyoma and then subsequently presented with benign metastasizing leiomyomas to her lungs. Due to her tumor being estrogen receptor (ER) positive and progesterone receptor (PR) positive, she was empirically treated with anastrozole with sustained clinical benefit. Molecular studies with Foundation One testing showed low mutational burden and mutational variants in five known cancer genes. Our findings have important clinical and pathogenetic implication for metastasizing uterine leiomyoma.

Positive Surgical Margins in Favorable-Stage Differentiated Thyroid Cancer.

OBJECTIVE: The significance of positive margin in favorable-stage well-differentiated thyroid cancer is controversial. We report outcomes of positive-margin patients with a matched-pair comparison to a negative-margin group. MATERIALS AND METHODS: A total of 25 patients with classic-histology papillary or follicular carcinoma, total thyroidectomy +/- node dissection, stage T1-3N0-1bM0, positive surgical margin at primary site, adjuvant radioactive iodine (I-131), and age older than 18 years were treated between 2003 and 2013. Endpoints were clinical and biochemical (thyroglobulin-only) recurrence-free survival. Matched-pair analysis involved a 1:1 match with negative-margin cases matched for overall stage and I-131 dose. RESULTS: Recurrence-free survival in positive-margin patients was 71% at 10 years. No patient was successfully salvaged with additional treatment. Only 1 patient died of thyroid cancer. Recurrence-free survival at 10 years was worse with a positive (71%) versus negative (90%) margin (P=0.140). CONCLUSIONS: Cure with a microscopically positive margin was suboptimal (71%) despite patients having classic-histology papillary and follicular carcinoma, favorable stage, and moderate-dose I-131 therapy.

Merkel Cell Carcinoma with Distant Metastasis to the Clivus Causing Symptoms Mimicking Tolosa-Hunt Syndrome: A Case Report and Literature Review.

Merkel cell carcinoma (MCC) is an uncommon but highly malignant neuroendocrine tumor of the skin. MCC can metastasize, but involvement of the central nervous system is rare. Here, we report a case of rapidly progressing metastatic MCC to the clivus and bilateral cavernous sinus in an immunocompromised patient. This case is unique in that it is the first case report showing MCC metastasis to the clivus from a distant site. It also demonstrates that a MCC metastasis can masquerade with symptoms of Tolosa-Hunt syndrome. A literature review on MCC with CNS metastasis is presented.

Favorable Outcome of Hurthle Cell Carcinoma of the Thyroid Treated With Total Thyroidectomy, Radioiodine, and Selective Use of External-Beam Radiotherapy.

OBJECTIVES: There is controversy about the prognosis of Hurthle cell carcinoma of the thyroid. The purpose of this project is to report the outcome of a well-defined group of patients treated at a single institution in the modern era. METHODS: Sixteen patients met the following inclusion criteria: Treatment with curative intent at our institution between January 1, 1997, and December 31, 2010. Primary treatment with total thyroidectomy with or without neck dissection. Age >18 years at the time of thyroidectomy. Confirmation by a pathologist of the diagnosis of a primary Hurthle cell carcinoma of the thyroid based on ≥75% Hurthle cells with extension through the tumor capsule. No areas of poorly differentiated (insular) or undifferentiated (anaplastic) carcinoma. Stage T1-3, NX-1b, M0. All patients received radioiodine immediately after thyroidectomy (remnant ablation, n=14) or as adjuvant for a recurrence (n=2). External-beam radiotherapy to the neck as adjuvant therapy after thyroidectomy was used in 2 patients and after resection of a neck recurrence in 1 patient. RESULTS: Five-year actuarial rates with a median 6 years of follow up on surviving patients were as follows:Overall and cancer-specific survival: 92% (1 death from Hurthle cell carcinoma). Relapse-free survival (no visible tumor and unstimulated thyroglobulin ≤1.0): 65%. CONCLUSIONS: Our experience suggests that the outcome of Hurthle cell carcinoma of the thyroid is favorable in adults with stage T1-3 NX-1b M0 disease who are managed with total thyroidectomy, radioiodine, and-in selected cases-external-beam radiotherapy. We do not have the ability to compare our results to other management strategies.

Hemangioblastoma in the lung: metastatic or primary lesions?

Hemangioblastoma primarily occurs in the CNS, most commonly in the posterior fossa. Extracranial locations are less common, and metastatic tumor involving the lung is exceedingly rare with only three cases previously reported. Two were autopsy studies in patients who died of complications of the CNS hemangioblastomas in 1943 and 1981, and the third was mentioned in a case report addendum providing follow-up information on hepatic hemangioblastoma in 1991. We report a case of a 48-year-old man who presented with multiple lung nodules treated by surgical excision. Pathological study revealed features classic for hemangioblastoma. The patient had a remote history of hemangioblastomas having been excised from the posterior fossa 7 and 20 years previously. This report details a fourth case of metastatic pulmonary hemangioblastoma. It is the first report on surgically resected hemangioblastomas from the lung of a living patient with histological and immunohistochemical characterization.

Smoothelin immunohistochemistry is a useful adjunct for assessing muscularis propria invasion in bladder carcinoma.

AIMS: To prospectively evaluate the utility of smoothelin immunohistochemical expression for the evaluation of muscularis propria (MP) in diagnostic transurethral resection of bladder tumour (TURBT) specimens and cystectomies. METHODS AND RESULTS: Smoothelin immunohistochemistry was performed on a total of 26 TURBT and cystectomy specimens. All but two cases (24/26) demonstrated strong (3+) or moderate (2+) immunoreactivity of the MP with smoothelin. Muscularis mucosae (MM) never displayed strong (3+) reactivity, and in only one case did the MM have moderate (2+) reactivity; in this case the MP had strong (3+) reactivity. MM intensity mirrored the intensity of reactivity of blood vessels in all cases (26/26). Using moderate or strong immunoreactivity as a cut-off, smoothelin had a sensitivity of 92% for detecting MP and a specificity of 97% for distinguishing between MP and MM. In all unequivocal MP-invasive and lamina proporia-invasive cases by haematoxylin and eosin (H&E), smoothelin immunohistochemistry confirmed the original light microscopic diagnosis. In four cases in which there was equivocal MP involvement by H&E, smoothelin helped establish MP invasion. CONCLUSIONS: Smoothelin immunohistochemistry has diagnostic utility in the evaluation of MP invasion in urothelial carcinoma. Smoothelin could be used as an adjunct to traditional H&E-stained light microscopy and may help reduce the number of equivocal diagnoses.

Clear cell adenocarcinoma of the bladder and urethra: cases diffusely mimicking nephrogenic adenoma.

Although clear cell adenocarcinoma have been described focally mimicking nephrogenic adenoma, we have identified a subset of clear cell adenocarcinoma that diffusely resembles nephrogenic adenoma (nephrogenic adenoma-like clear cell adenocarcinoma). Twelve classic clear cell adenocarcinomas of the bladder and urethra and 7 nephrogenic adenoma-like clear cell adenocarcinomas were compared to 10 nephrogenic adenomas. Classic clear cell adenocarcinomas and nephrogenic adenoma-like clear cell adenocarcinomas comprised 4 men and 15 women. The following features were seen in classic clear cell adenocarcinomas: nephrogenic adenoma-like clear cell adenocarcinomas: predominantly solid pattern (7/12:0/7), marked nuclear pleomorphism (7/12:1/7), prominent nucleoli (5/12:1/7), clear cytoplasm in 50% or greater of tumor (7/12:0/7), and necrosis (8/12:3/7), although the necrosis in nephrogenic adenoma-like clear cell adenocarcinomas was often focal and intraluminal. Both patterns of clear cell adenocarcinomas showed prominent hobnail features, although more pronounced in nephrogenic adenoma-like clear cell adenocarcinomas. Muscularis propria invasion was seen in 5 of 9 classic clear cell adenocarcinomas and 6 of 6 nephrogenic adenoma-like clear cell adenocarcinomas, where evaluable. Classic clear cell adenocarcinoma was associated with urothelial carcinoma (n = 2) and endometriosis (n = 1). The Ki-67 rate in clear cell adenocarcinomas ranged from 10% to 80% compared with 0% to 5% in nephrogenic adenoma. The following antibodies were not helpful in distinguishing nephrogenic adenoma-like clear cell adenocarcinoma from nephrogenic adenoma: CD10, estrogen receptor, p63, high-molecular-weight cytokeratin, and alpha-methylacyl coenzyme-A racemase. PAX2 expression was more frequent in nephrogenic adenoma (89%) compared to both patterns of clear cell adenocarcinoma (29%-32%). The key features discriminating between nephrogenic adenoma-like clear cell adenocarcinoma and nephrogenic adenoma include occasional clear cells, more prominent pleomorphism especially hyperchromatic enlarged nuclei, and extensive muscular invasion. Presence of mitoses and a high rate of Ki-67 expression in lesions resembling nephrogenic adenoma require clinical correlation, close follow-up, and repeat biopsy with more extensive sampling.

Characterization of papillary squamotransitional cell carcinoma of the cervix.

OBJECTIVE: Does papillary squamotransitional cell carcinoma (PSTCC) behave differently from conventional squamous cell carcinoma of the cervix and does PSTCC have true transitional cell differentiation? MATERIALS AND METHODS: Twenty cases of PSTCC were identified from archival files. Clinical data were compiled. Immunoperoxidase stains for uroplakin III, p63 and p16 were performed on available tissue blocks. RESULTS: Patients ranged in age from 27 to 85 years. Twelve patients were FIGO Stage I, 4 were Stage II, and 2 were Stage III. Thirteen patients had clinical follow-up ranging from 5 to 132 months. Three patients subsequently had more extensive disease than initial clinical staging indicated. Nine patients had no tumor progression, three had local recurrence and one had metastatic disease. Eight cases were strongly immunoreactive for p63 and p16 and 14 were negative for uroplakin III. CONCLUSIONS: PSTCC lacks true transitional cell differentiation and probably shares similar clinicopathologic features with conventional cervical squamous cell carcinoma.