The Small Round Blue Cell Tumors of Sinonasal Tract: Pathologists Grey Zone.

Background: One of the most challenging diagnostic categories in the sinonasal tract includes small-blue-round-cell tumors. These are malignant tumors which show many overlapping histomorphology and immunohistochemistry (IHC) findings. Limited, small biopsy of these not completely excisable tumors adds to the diagnostic confusion. Materials and Methods: A cross-sectional study was done for 2 years (January 2018-December 2020) in a tertiary care institute, which included 70 cases of tumors of which 49 cases were malignant. All paraffin-embedded blocks were subjected to hematoxylin and eosin stain and IHC followed by molecular study wherever needed. Results: Of the total cases, small-blue-round-cell tumor constituted the major category comprising 20 rare and interesting cases which included sinonasal undifferentiated carcinoma (4 cases), malignant lymphoma (2 cases of diffuse large B-cell lymphoma and 2 cases of extranodal natural killer/T-cell lymphoma), rhabdomyosarcoma (2 cases), olfactory neuroblastoma (2 cases), malignant melanoma (2 cases), plasmacytoma (2 cases), atypical Ewing's sarcoma (EWS) (1 case), EWS (1 case), nuclear protein in testis (NUT) carcinoma (1 case), and small-cell neuroendocrine carcinoma (1 case). Conclusion: Tumors of the sinonasal tract are very diverse, more so in small-round-cell tumor which present with a undifferentiated morphology. Thus, accurate diagnosis needs clinicoradiological parameters and special ancillary techniques such as IHC and molecular study in addition to histopathology for early diagnosis and therapy to prevent significant morbidity and mortality caused in these tumors.

Expression of Gata Binding Protein 3 as a Prognostic Factor in Urogenital Lesions and Its Association With Morphology.

BACKGROUND: Urogenital malignancies, encompassing urinary bladder cancer, prostate cancer, and renal cell carcinoma, pose significant diagnostic challenges due to overlapping histopathological features. GATA binding protein 3 (GATA3), a transcription factor associated with urothelial tissue, has shown promise as a potential diagnostic marker. This study aimed to investigate the incidence of these malignancies, explore GATA3's involvement in urothelial cancer (UC), and determine its role in distinguishing urogenital malignancies. MATERIALS AND METHODS: A cross-sectional, retro-prospective, hospital-based study was conducted from May 2019 to April 2021. The surgical samples of patients who underwent transurethral resection of bladder tumour (TURBT), transurethral resection of the prostate (TURP), radical cystoprostatectomy, total and partial radical nephrectomy specimens during the study period were reviewed. Patients diagnosed with urinary bladder neoplasm and high-grade prostate neoplasm along with chromophobe, oncocytic, sarcomatoid variant and clear cell carcinoma, renal cell carcinoma were included. Immunohistochemical analysis of GATA3 expression was performed, with scoring based on nuclear staining intensity and percentage of tumor cells labeled. RESULTS: The study included 64 patients, predominantly males over 60 years. Personal habits revealed a high prevalence of smoking (85.9%). The most prevalent symptom was hematuria (75.0%), followed by hematuria with urgency (20.3%). The most common site of lesion was posterolateral (31.3%). Urothelial cancer was the most common malignancy, primarily high-grade. Strong positive GATA3 expression was significantly associated with high-grade UC (p=0.01) and invasion (p=0.01). However, low-grade UC and papillary urothelial neoplasm of low malignant potential exhibited moderate GATA3 expression. GATA3 demonstrated potential for distinguishing UC from other histological types. CONCLUSION: GATA3 expression correlates with high-grade urothelial cancer and invasive behavior, suggesting its utility as a diagnostic marker in challenging cases.

Imprint Cytology Can Be a Better Option for Diagnosis of Mammary Paget's Disease!!!: A Case Report with Review.

Mammary Paget's disease (MPD) is a rare form of pruritic eczematous skin lesion involving the nipple areola complex usually associated with an underlying in-situ or invasive carcinoma of breast, accounting ≤ 4% of overall breast carcinoma. The patient may present with nipple discharge, eczema, plaque, or nipple destruction with or without a lump which is resistant to common remedies. Diagnosis of MPD is usually accomplished by a punch biopsy, but imprint cytology is found to be an effective modern technique yet less explored. Cytological diagnosis is advantageous over surgical excisional biopsy; advantages being easy practicability, cost-effective, quick non-invasive, and above all can lead the physician for breast-preserving surgeries in selective cases rather than more aggressive standard mastectomies. We report one such case of MPD in a 52-year-old female diagnosed on imprint cytology with the aim to emphasize that imprint cytology can be a better option to improve the treatment protocol.

An Unusual Presentation of Extra-Oral Plasmablastic Lymphoma With Unique Cytomorphology.

Plasmablastic lymphomas are high-grade lymphomas most commonly observed in the oral cavity. Their association with HIV-infected patients is now well-known. The occurrence of plasmablastic lymphomas in extra-oral sites in immunocompetent patients is exceedingly rare. We aim to document such a rare case in a 69-year- old female in the gastrointestinal tract along with lymphomatous effusion of the pleural cavity. The discussed case also needs a mention for its unique cytomorphological features. The diagnosis was confirmed by immunohistochemical stains, which play a vital role in the accurate diagnosis of plasmablastic lymphomas and their distinction from other anaplastic non-Hodgkin lymphomas.

Nasopharyngeal carcinoma ex-pleomorphic adenoma (noninvasive): A report of a rare case.

Pleomorphic adenoma (PA) is the most common type of benign tumors of minor salivary glands. A carcinoma ex-pleomorphic adenoma (CXPA) is a malignant epithelial neoplasm originating from either a primary or recurrent benign PA. The nasopharynx is an extremely uncommon location for this tumor. A 32-year-old male had complaints of nasal blockage. In noncontrast computed tomography, a soft-tissue mass was present in the nasopharynx. Histopathological and immunohistochemical examination of the endoscopically excised mass revealed features of CXPA, noninvasive in nature. Careful histopathological examination is the key to identify this uncommon entity. To the best of our knowledge, <20 cases have been published so far.

Metastatic hobnail variant of papillary thyroid carcinoma: A diagnostic challenge in cell block preparation.

Hobnail variant of papillary thyroid carcinoma (HV-PTC) is an unusual entity recently included in WHO classification of endocrine tumors (2017) and proposed as an aggressive variant of PTC. Compared to patients of classical counterparts, HV-PTC frequently has extrathyroidal extension, exhibits nodal or distant metastasis, and responds poorly to radioiodine treatment, leading to increased mortality. We hereby describe the cytohistological and immunohistochemical features of a metastatic HV-PTC in 55-year-old male, previously diagnosed as poorly differentiated papillary thyroid carcinoma in thyroidectomy specimen. Five years after total thyroidectomy with radical neck dissection the patient presented with gross pleural effusion showing multiple lung parenchymal and pleural based lesions with complete collapse of lung on computed tomography scan. The conventional cytology of pleural fluid showed dyscohesive cells arranged in micropapillary form gave the suggestion of metastatic papillary carcinoma. But the cell block preparation highlighted >30% hobnail cells arranged in micropapillary pattern showing increased atypical mitosis and occasional pseudoinclusions. Supplemented with immunohistochemistry (CK19, TTF-1, and p53), final diagnosis HV-PTC was made.

Intracranial Solitary Fibrous Tumor/Hemangiopericytoma: A Clinicoradiological Poorly Recognized Entity- An Institutional Experience.

AIM: Intracranial solitary fibrous tumors (SFTs) and hemangiopericytomas (HPCs) are rare nonmeningothelial mesenchymal tumors sharing fusion of NGF1-A binding protein 2 (NAB2) and signal transducers and activators of transcription (STAT6.).The WHO classification of central nervous system (CNS) tumors (2016) highlights that molecular confirmation of NAB2/STAT6 fusion or immunohistochemical nuclear expression of STAT6 is mandatory for the diagnosis of SFT/HPC.Herein, we present a series of four cases of SFT/HPC of the brain, which mimicked other CNS tumors both clinically and radiologically. MATERIAL AND METHODS: This is a retrospective study over a period of two and a half years. Out of the 156 operated cases of brain tumors, four patients (2.56%) were diagnosed with SFT/HPC. The clinicoradiological details with the surgical procedure were retrieved from the archived hospital records. RESULTS: All cases were males, of which three were in their 5th decade while one was a 14-month-old baby. Two cases were primary and the rest were recurrent.The location of tumors was extra-axial left cerebellotentorial,clivaldural-based,left cerebellar, and in the left frontoparietal region,respectively. The clinical impression was meningioma in three cases,while it was primitive neuroectodermal tumor (PNET) /atypical teratoid/rhabdoid tumor (ATRT) in one case.With the detailed histomorphology and immunohistochemistry, the final diagnosis was anaplastic hemangiopericytoma(WHO grade III) for all the cases. During our follow-up, one patient died with the disease, while the rest are doing well. CONCLUSION: SFT/HPC should be kept in the differential diagnosis of all dura-based hypervascular masses, especially in recurrent cases, due to its aggressiveness and high recurrence rate.