Metastatic choriocarcinoma of the kidney in the absence of existing primary uterine tumor: A rare presentation.

Gestational choriocarcinomas are malignant neoplasms generally arising in the uterus in women of childbearing age. These are aggressive tumors with a high incidence of metastasis to vascular organs such as the lung, liver, and brain. Renal metastasis is extremely rare with low incidence rate and very few cases have been reported in literature. Hereby, we report a rare case of metastatic choriocarcinoma to the kidney in a 29-year-old female 10 years after resection of a hydatidiform mole. The histopathological diagnosis was made on a nephrectomy specimen. Pelvic and abdominal scan did not show any abnormal radiological findings. She was started on first-line chemotherapy and showed a complete response. In conclusion, gestational or primary nongestational choriocarcinomas should always be considered as a differential diagnosis in young females of reproductive age group presenting with flank abdominal pain, unexplained hematuria, and atypical renal tumor histology.

Correlation NKX2.2 IHC and EWSR1 break-apart FISH in the diagnosis of Ewing sarcoma: Can combined NKX2.2 and CD99 immunoexpression obviate or minimize the need of FISH testing? First assessment study from Indian tertiary cancer care center.

Context: Ewing sarcoma (ES) are malignant small round cell tumors (MSRCT) characterized by rearrangements of EWSR1 gene. Although gold standard for diagnosis is detection of specific fusion genes by molecular testing, these ancillary tests are costly and only available in limited number of settings. There is a persuasive evidence for reliability of NKX2.2 immunohistochemistry (IHC) as a surrogate marker for EWSR1 gene rearrangement in ES. Aims: The aim of this study is to correlate the NKX2.2 immuno-expression with genetically confirmed ES cases and also to assess the reliability and accuracy of NKX2.2 along with combined positivity of NXX2.2 and CD99 in diagnosing ES and differentiating it from other relevant histological mimics. Settings and Design: The present study is a retrospective study conducted over a period of 6-year duration in a tertiary cancer care center. Methods and Material: We evaluated NKX2.2 immunoexpression in 35 genetically confirmed cases of ES and also in pertaining differential entities (n = 58) of ES including rhabdomyosarcoma (n = 20), lymphoblastic lymphoma (n = 14), Wilms tumor (n = 10), poorly differentiated synovial sarcoma (n = 4), small-cell osteosarcoma (n = 4), neuroblastoma (n = 5), and mesenchymal chondrosarcoma (n = 1). CD99 was performed in the category of MSRCTs showing NKX2.2 positivity to evaluate combined specificity for the diagnosis of ES. Results: Of the 35 genetically confirmed cases of ES, 29 cases (83%) showed NKX2.2-positive expression (83% sensitivity). Compared to ES, NKX2.2 was positive in only 05% cases (3/58 cases) of non-ES MSRCT. Only two of five cases of neuroblastomas and one case of mesenchymal chondrosarcoma showed NKX2.2 positivity. CD99 positivity was seen in 100% of ES and in the single case of mesenchymal chondrosarcoma. All five cases (100%) of neuroblastoma were negative for CD99. Conclusions: The presented study, which is the first from an Indian oncology center, showed NKX2.2 IHC is quite reliable in diagnosis of ES in the right clinicopathological context. With remarkable sensitivity and specificity of NKX2.2 IHC for diagnosis of ES, we propose that combined positivity of CD99 and NKX2.2 IHC can obviate or minimize the need of EWSR1 gene rearrangement molecular testing for diagnosis of ES.

Reclassification of Salivary Gland Aspirates Based on "The Milan System for Reporting Salivary Gland Cytology": A Five-Year Retrospective Study.

Introduction: The Milan System for reporting salivary gland cytopathology helps standardize reporting systems across institutions, improve communication between clinicians and pathologists and guide the clinical management of patients. Aims: This study was undertaken to evaluate the utility of the Milan system classification in cytology reporting. Settings and Design: The present study is a retrospective study conducted over a period of five years in tertiary care centre. Methods and Materials: All the cases of salivary gland aspirates were reviewed and reclassified into six diagnostic categories according to the Milan system of reporting salivary gland cytology (MSRSGC). Cytological diagnosis was correlated with the histopathological diagnosis wherever available. Results: A total of 258 cases were classified using the Milan system as non-diagnostic (20.9%), non-neoplastic (26.3%), atypia of undetermined significance (4.7%), neoplasm benign (37.5%), neoplasm of uncertain malignant potential (3.5%), suspicious for malignancy (0.4%), and malignancy (6.6%). Cytohistological discordance was noted among 8/76 cases (10.5%). The sensitivity and specificity of FNAC were 75% and 98.5%, respectively. The risk of malignancy was 14.2% for Category I, 9% for II, 50% for III, zero for IVA and IVB, and 83.3% for category VI. Conclusions: The new classification system helps pathologists to standardize reporting leading to better clinical and surgical management.

Intraventricular metastasis from carcinoma breast masquerading as choroid plexus neoplasm: A case report.

Metastatic tumors in the brain represent the most common type of intracranial neoplasm, comprising 8-10% of all brain tumors. 30% of such tumors are primarily of breast origin in females. Brain parenchymal metastasis is the more common presentation. Intraventricular spread is rare, seen in less than 5% of cases in a metastatic scenario. Here, we report a case of 41-year-old female presenting with intraventricular brain metastasis in a follow-up case of carcinoma breast. Five years post-surgery, the patient presented with complaints of headache. On evaluation, magnetic resonance imaging (MRI) brain showed an intraventricular lesion in the fourth ventricle. She was operated on for the same and the biopsy revealed a tumor with a complex papillary pattern resembling choroid plexus papilloma. On immunohistochemistry (IHC), the tumor cells were positive for cytokeratin 7 (CK7), Epithelial membrane antigen (EMA), GATA3, and mammaglobin favoring a metastasis from breast origin. Hence, a possibility of brain metastasis should be kept in mind in patients presenting with solitary ventricular masses due to the lack of definite radiological characteristics in such locations and histological overlap. Also, organ-specific IHC is a must in today's evidence-based era as is reflected in our case.

Adamantinoma-like Ewing Sarcoma of the Nasal Cavity: A Rare Clinical Presentation with Deceptive Histopathologic Features.

Ewing sarcoma (ES) is a malignant round cell tumour (MRCT) that usually involves bone and soft tissue of young and paediatric populations. ES of the head and neck region is uncommon. Adamantinoma-like Ewing sarcoma (ALES) is a rare variant of ES that shows complex epithelial differentiation on histopathology and immunohistochemistry (IHC). It demonstrates a t(11;22) translocation and EWSR1- FLI1 fusion. Most documented cases of ALES of the head and neck region were initially misdiagnosed as epithelial tumours. We present a rare case of ALES of the nasal cavity in a young female. The patient subsequently underwent chemotherapy and showed an excellent response. Awareness of this entity is important for pathologists and oncologists due to its distinct therapeutic and prognostic implications. We propose performing upfront NKX2.2 and CD99 IHC studies, as well as other lineage specific IHC markers, in any poorly differentiated MRCT of head and neck region.