Improved artificial intelligence discrimination of minor histological populations by supplementing with color-adjusted images.

Despite the dedicated research of artificial intelligence (AI) for pathological images, the construction of AI applicable to histopathological tissue subtypes, is limited by insufficient dataset collection owing to disease infrequency. Here, we present a solution involving the addition of supplemental tissue array (TA) images that are adjusted to the tonality of the main data using a cycle-consistent generative adversarial network (CycleGAN) to the training data for rare tissue types. F1 scores of rare tissue types that constitute < 1.2% of the training data were significantly increased by improving recall values after adding color-adjusted TA images constituting < 0.65% of total training patches. The detector also enabled the equivalent discrimination of clinical images from two distinct hospitals and the capability was more increased following color-correction of test data before AI identification (F1 score from 45.2 ± 27.1 to 77.1 ± 10.3, p < 0.01). These methods also classified intraoperative frozen sections, while excessive supplementation paradoxically decreased F1 scores. These results identify strategies for building an AI that preserves the imbalance between training data with large differences in actual disease frequencies, which is important for constructing AI for practical histopathological classification.

Cytological Features of Carcinosarcoma ex Pleomorphic Adenoma of the Parotid Gland: A Case Report.

BACKGROUND: Carcinosarcoma of the salivary gland is an extremely rare tumor composed of carcinomatous and sarcomatoid components. This report describes the cytological and pathological findings of a case of carcinosarcoma ex pleomorphic adenoma arising in the right parotid gland. CASE: A 47-year-old female visited a hospital with swelling of the right parotid region, slight pain and facial palsy. Fine-needle aspiration smears showed both clustered epithelium-like cells and singly scattered cells in a necrotic background. The cells, especially the latter, exhibited significant cellular pleomorphism and had irregularly shaped nuclei. Myxoid stroma-like cell clusters without cellular atypism were also seen. The right parotid gland was resected, and the tumor tissue was histologically diagnosed as carcinosarcoma ex pleomorphic adenoma. CONCLUSION: The cytological findings of carcinosarcoma ex pleomorphic adenoma have been reported in very few cases. In the present case, various components, including the presence of atypical epithelium-like cell clusters and singly scattered atypical cells with stromal components on cytological specimens, led to consideration of the diagnosis of carcinosarcoma ex pleomorphic adenoma.

Collagenous spherulosis associated with adenomyoepithelioma of the breast: a case report.

BACKGROUND: Collagenous spherulosis (CS) associated with an adenomyoepithelioma (AME) of the breast is rare. This report describes a case of CS associated with an AME of the right breast, including the cytologic and histopathologic findings. CASE: A 51-year-old female presented with a slow-growing left breast mass that had been present for 5 months. A preoperative core needle biopsy showed the presence of layers or sheaths of myoepithelial cells around epithelial-lined spaces. Imprint cytology of the surgical material showed the presence of bundles of spindle cells with an admixture of epithelial cells. Spherical structures were also found. They were translucent or slightly light green with Papanicolaou staining and metachromatic with Giemsa staining. Grossly, the 1.5-cm lesion was solid and embedded within the breast parenchyma. Microscopically, it was composed of spindle or polygonal cells with eosinophilic cytoplasm and an epithelium lining spaces with many spherical structures. The spindle or polygonal cells were positive for myoepithelial markers and the epithelium was positive for epithelial markers by immunohistochemistry. CONCLUSION: There is no previous report describing the cytologic findings of CS associated with an AME of the breast. AMEs should therefore be considered an underlying pathology of CS of the breast.

Imprint cytologic features in renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusion in an adult: a case report.

BACKGROUND: Adult-onset renal cell carcinoma (RCC) associated with Xp11.2 translocation/TFE3 gene fusion is a very rare tumor. To date, there are no reports on immunocytochemical study of the primary tumor. We describe such a case that we diagnosed by immunocytochemistry of imprint cytology material. CASE: A 46-year-old man was found to have a mass in the lower pole of the right kidney. Magnetic resonance imaging (MRI) T2-weighted images showed a hypointense area in the tumor, and papillary RCC was suspected. Imprint cytology showed tumor cells that were isolated or arranged in large or small papillary clusters. Irregularly shaped large oval nuclei, finely granular chromatin and a single large nucleolus were noted. Cytoplasm was abundant and admixed with clear and granular eosinophilic patterns and scattered large vacuolated cells. Almost all tumor cells diffusely expressed immunocytochemical reactivity to TFE3 protein. Hyaline nodules were observed in the stroma. Ultrastructurally, neoplastic cells contained rhomboid crystals identical to those of alveolar soft part sarcoma. CONCLUSION: The immunocytochemistry of TFE3 protein may be a powerful tool for accurate diagnosis when RCC associated with Xp11.2 translocation/TFE3 gene fusion is suspected by imprint cytology even in adult-onset cases, and cytotechnologists should accurately recognize cytologic findings of this tumor.

Chromophobe renal cell carcinoma: useful diagnostic application of imprint cytology and fluorescence in situ hybridization of chromosomes 10 and 21 in two cases of typical and eosinophilic variants.

Chromophobe renal cell carcinoma (RCC) is subdivided into typical and eosinophilic variants. We report such two cases with focus on imprint cytology and fluorescence in situ hybridization (FISH). The first case is a 53-year-old Japanese man and the second is a 76-year-old Japanese man. Histologically, the diagnosis of typical and eosinophilic variants of chromophobe RCC was suspected. In imprint cytology, irregularity of nuclear membrane, binucleation, perinuclear halo, and thick cell border were observed. Immunohistochemically, neoplastic cells of both tumors were positive for cytokeratin 7, E-cadherin, c-kit, and CD10. In FISH study, both tumors revealed the monosomy of chromosomes 10 and 21. Additionally, FISH study in eosinophilic variant of chromophobe RCC showed the disomy of chromosomes 7 and 17. In conclusion, we suggest that the combination study of imprint cytology and FISH of chromosomes 10 and 21 as well as routine histology may contribute to the accurate diagnosis of chromophobe RCC.

Paranuclear blue inclusions of small cell carcinoma of the stomach: report of a case with cytologic presentation in peritoneal washings.

BACKGROUND: Primary gastric small cell carcinoma is a rare but important entity. We describe a case that we diagnosed by peritoneal washing cytology. CASE: A 70-year-old male presented with upper abdominal discomfort and underwent endoscopic evaluation. Gastric endoscopy revealed a diffuse, infiltrating tumor from the body to the antrum. Total gastrectomy with lymph node dissection and intraoperative peritoneal washing cytology were carried out. Peritoneal washing cytology showed the presence of many undifferentiated malignant small cells with a necrotic background. The tumor cells were small and round, with naked, hyperchromatic nuclei and finely granular chromatin. Some tumor cells contained paranuclear blue inclusions (PBls) in the cytoplasm. The tumor cells were positive for neuron-specific enolase and synaptophysin on immunocyto-chemistry. Carcinoembryonic antigen, alpha-fetoprotein (AFP) and leukocyte common antigen were negative. Pathologic diagnosis after the operation was moderately to poorly differentiated adenocarcinoma and small cell carcinoma containing AFP-positive cells. CONCLUSION: The prognosis of primary gastric small cell carcinoma is usually poor. Our patient died of multiple liver metastases and peritonitis carcinomatosa 69 days after surgery. When a gastric small cell carcinoma is suspected in peritoneal washings, immunocytochemical demonstration of neuroendocrine differentiation is required to arrive at the final diagnosis.

Primary pulmonary leiomyosarcoma. Report of a case diagnosed by fine needle aspiration cytology.

BACKGROUND: Primary pulmonary leiomyosarcoma is a rare but important entity. We report a case diagnosed by fine needle aspiration cytology. CASE: A 73-year-old male presented with an asymptomatic, right, pulmonary, subpleural nodule detected by computed tomography during follow-up for chronic obstructive pulmonary disease. Fine needle aspiration cytology showed cellular smears with numerous single or loosely cohesive groups of spindle-shaped to round cells. The tumor cell nuclei were blunt ended (cigar shaped), with fine to fine-granular chromatin, prominent nucleoli and an irregular nuclear rim. The tumor cells were positive for desmin and negative for cytokeratin and S-100 protein by immunocytochemistry. Right upper lobectomy with lymph node dissection was performed. Pathologic diagnosis after microscopic, immunohistochemical and electron microscopic studies was leiomyosarcoma. CONCLUSION: To our knowledge, this is the first reported case of primary pulmonary leiomyosarcoma arising in the subpleural region diagnosed by fine needle aspiration cytology. Immunocytochemistry was useful in establishing the diagnosis in this case.