Myofibroblastoma of the breast showing rare palisaded morphology and uncommon desmin- and CD34-negative immunophenotype: A case report.

Myofibroblastoma is a rare benign mesenchymal tumor typically arising in the breast. We report a diagnostically challenging case of myofibroblastoma of the breast showing a rare palisaded morphology and an uncommon desmin- and CD34-negative immunophenotype. A 73-year-old man underwent an excision for an 8 mm-sized breast mass. Histology revealed that the tumor was composed of fascicles of bland spindle cells showing prominent nuclear palisading and Verocay-like bodies. First, schwannoma, malignant peripheral nerve sheath tumor, and synovial sarcoma were suspected given the palisaded morphology. However, none of them was confirmed by immunohistochemical or molecular analyses. Next, a palisaded variant of myofibroblastoma was suspected by the morphology and coexpression of estrogen, progesterone and androgen receptors, BCL2 and CD10 in immunohistochemistry. However, the key diagnostic markers, desmin and CD34, were both negative. Finally, the diagnosis of myofibroblastoma was confirmed by detecting RB1 loss in immunohistochemistry and monoallelic 13q14 deletion (RB1 and FOXO1 loss) by fluorescence in situ hybridization assay. For the correct diagnosis of myofibroblastoma, it is important for pathologists to recognize the wide morphological spectrum, including a palisaded morphology, and the immunophenotypical variations, including desmin- and CD34-negative immunophenotypes, and to employ a comprehensive diagnostic analysis through combined histological, immunohistochemical and molecular evaluations.

Characteristic Cytological Findings of Lobular Endocervical Glandular Hyperplasia Associated with Adenocarcinoma of the Uterine Cervix.

OBJECTIVE: To investigate the cytological findings of lobular endocervical glandular hyperplasia (LEGH) associated with adenocarcinoma and to clarify its characteristics and the coexisting adenocarcinoma using histochemistry and immunohistochemistry. METHODS: Eighteen surgical cases of LEGH of the uterine cervix were retrospectively reviewed and classified into 3 groups: pure (pure type), atypical (atypical type), and LEGH with adenocarcinoma (mixed type). The mixed type is defined as LEGH or atypical LEGH with in situ or invasive adenocarcinoma. Cytological findings of conventional endocervical smear specimens (Papanicolaou stain) were analyzed. Histochemistry (periodic acid-Schiff reaction) and immunohistochemistry (M-GGMC-1, Muc-6 glycoprotein, and Ki-67) were performed using tissue specimens. RESULTS: Cytologically, the pure type (7 cases) is characterized by glandular cell clusters that tended to form monolayered sheets with uniformly small nuclei and contain golden-yellowish mucin, whereas atypical (5 cases) and mixed (6 cases) types are characterized by glandular cell clusters similar to those of the pure type, but with complex glandular structures and mucin localization on the surface of glandular cell clusters. Ki-67 labeling index was significantly higher in atypical and mixed types than that in the pure type. Gastric-type mucinous carcinoma (MC-G) was observed in 2 out of 6 cases with mixed type. CONCLUSIONS: LEGH is found to be associated with adenocarcinoma types other than MC-G. Complex glandular structures or mucin localization on the surface of glandular cell clusters may be useful cytological findings to detect atypical and mixed types of LEGH.

Clinical management of the status of atypical endometrial cells using the descriptive reporting format for endometrial cytology.

OBJECTIVE: We aimed to develop and reinforce a clinical management regimen for atypical endometrial cell (ATEC) categories within the descriptive reporting format for endometrial cytology. METHODS: Between January 2013 and December 2014, 215 samples, for which histological examination was performed immediately or within 3 months after cytology, were cytologically diagnosed as ATEC. For these samples, the medical records were retrospectively reviewed to identify risk factors for malignancy. RESULTS: Among 152 samples diagnosed as ATEC, of undetermined significance, 19 (12.5%) were malignant. In the younger group (age <55 years), the χ2 values of body mass index (BMI) ≥25 kg/m2 (5.85), gravidity (5.64) and parity (5.15) were relatively high, suggesting that these were risk factors for malignancy. Of the nulligravida patients, those with BMI ≥25 kg/m2 , 28% were diagnosed with malignant disease. In the older group (≥55 years), endometrial thickening (6.84), atypical genital bleeding (6.43) and BMI ≥25 kg/m2 (3.79) were found to be risk factors for malignancy. Of the patients with endometrial thickening and atypical genital bleeding, 67% were diagnosed with malignant disease. Among 63 samples diagnosed as ATEC, cannot exclude atypical endometrial hyperplasia or more, 35 (55.6%) samples were positive for malignancy. CONCLUSIONS: High-risk patients diagnosed with ATEC, of undetermined significance were identified. Endometrial biopsy should be considered for nulligravida patients aged <55 years with a BMI ≥25 kg/m2 .

Cytological Findings of Gastrointestinal Stromal Tumor-Derived Bone Metastasis.

OBJECTIVE: Procedures for diagnosing bone tumors should be rapid and minimally invasive. Thus, cytological examinations are more useful for such purposes than histological examinations. In order to identify cytomorphological findings that could be used to diagnose bone metastasis from gastrointestinal stromal tumors (GIST), previous cases were reviewed. STUDY DESIGN: Cytological samples of 7 lesions from 4 patients with GIST-derived bone metastasis, which were obtained from 2001 to 2017 at the JFCR Cancer Institute Hospital, were reviewed. RESULTS: The metastasis of GIST to the bone was clinically suspected before the cytological and histological examinations in all cases since they all involved other metastatic lesion(s), and characteristic osteolytic lesions were detected on radiological images. Although various cell shapes were encountered, spindle cell proliferation was seen in all cytological samples. No pleomorphism was apparent. Characteristic nuclear findings were observed. All of the cases could be diagnosed as GIST-derived bone metastasis. CONCLUSION: GIST-derived bone metastasis can be diagnosed by examining cytological samples.

Touch cytology smear of an inflammatory hepatocellular adenoma displaying an unusual pattern: A case report.

The cytological diagnosis of hepatocellular adenoma (HCA) is difficult since it is a very rare tumor and lacks characteristic cytological features. We have just reported a case of inflammatory HCA that displayed an unusual histological pattern (Clin J Gastroenterol 8:426-434, 2015). A touch cytology smear sample was obtained from the surgical specimen, and it also exhibited very unique features. A 56-year-old male underwent partial hepatectomy for an inflammatory HCA (diameter: 1.4 cm) in the right posterior lobe of the liver. The cytological sample displayed a characteristic two-cell pattern. One type of cells contained thick cytoplasm, a high nucleus/cytoplasmic (N/C) ratio, and well-defined cytoplasmic borders. The other type demonstrated small pyknotic nuclei and a lower N/C ratio. The immunohistochemical staining pattern of the histological specimen suggested that the latter cells might have been undergoing apoptosis. We report a case of inflammatory HCA with characteristic features. To diagnose this type of variant, it is important to recognize the unique pattern described in this study. Diagn. Cytopathol. 2016;44:1074-1077. © 2016 Wiley Periodicals, Inc.

Rhizobium-legume symbiosis in the absence of Nod factors: two possible scenarios with or without the T3SS.

The occurrence of alternative Nod factor (NF)-independent symbiosis between legumes and rhizobia was first demonstrated in some Aeschynomene species that are nodulated by photosynthetic bradyrhizobia lacking the canonical nodABC genes. In this study, we revealed that a large diversity of non-photosynthetic bradyrhizobia, including B. elkanii, was also able to induce nodules on the NF-independent Aeschynomene species, A. indica. Using cytological analysis of the nodules and the nitrogenase enzyme activity as markers, a gradient in the symbiotic interaction between bradyrhizobial strains and A. indica could be distinguished. This ranged from strains that induced nodules that were only infected intercellularly to rhizobial strains that formed nodules in which the host cells were invaded intracellularly and that displayed a weak nitrogenase activity. In all non-photosynthetic bradyrhizobia, the type III secretion system (T3SS) appears required to trigger nodule organogenesis. In contrast, genome sequence analysis revealed that apart from a few exceptions, like the Bradyrhizobium ORS285 strain, photosynthetic bradyrhizobia strains lack a T3SS. Furthermore, analysis of the symbiotic properties of an ORS285 T3SS mutant revealed that the T3SS could have a positive or negative role for the interaction with NF-dependent Aeschynomene species, but that it is dispensable for the interaction with all NF-independent Aeschynomene species tested. Taken together, these data indicate that two NF-independent symbiotic processes are possible between legumes and rhizobia: one dependent on a T3SS and one using a so far unknown mechanism.

Usefulness of intraoperative imprint cytology in ovarian germ cell tumors.

OBJECTIVE: This study retrospectively investigated the usefulness of intraoperative diagnosis based on imprint cytology and frozen sections for ovarian germ cell tumor. STUDY DESIGN: Intraoperative studies were reviewed for 23 cases with ovarian germ cell tumor treatment for which both frozen sections and imprint cytology were available. Final histopathologic diagnoses were compared with those based on intraoperative examinations. RESULTS: Underlying pathologies included dysgerminoma (n = 6), yolk sac tumor (n = 1), non-gestational choriocarcinoma (n = 1), mature cystic teratoma with malignant transformation (n = 1), immature teratoma (n = 11), and mixed germ cell tumor (n = 3). Discrepancies between intraoperative imprint cytology and definitive histologic diagnosis were seen in 6 of the 23 cases. Accuracy was 54.5% (6/11) for immature teratoma and 91.7% (11/12) for other tumors. Cytologic examination facilitated accurate diagnosis in both of our cases, and intraoperative diagnosis by frozen section proved inaccurate. CONCLUSION: These results demonstrate that intraoperative assessment based on imprint cytology for immature teratoma has a relatively lower sensitivity, but an acceptable sensitivity for other germ cell tumors. Diagnostic approaches combining frozen sections and imprint cytology are advisable to improve the yield for intraoperative diagnosis.

Discriminant analysis of malignant mesothelioma and reactive mesothelium using three-dimensional nuclear estimation.

OBJECTIVE: The cytological diagnosis of coelomic fluid is essential for examining malignant mesothelioma (MM). However, reactive mesothelium (RM), caused by various factors, is morphologically similar to MM and thus often complicates the differential diagnosis. Here, nuclear luminance and steric alterations were assessed for the discriminant analysis of MM and RM. STUDY DESIGN: Thirteen epithelial MM and 11 RM cases were included. One hundred alterations in the numbers of nuclear pixels and focus layers and the coefficient of variation of nuclear luminance among layers were determined for each case to conduct discriminant analysis using the Mahalanobis distance. RESULTS: A cutoff value of 0.072 allowed highly accurate discrimination of MM (89.5%) and RM (89.6%). Fifteen cells appeared in 6 agglomerates of indiscriminable MM cases. The 6 agglomerates were individually examined. Malignant cells were dominant in 3 agglomerates (50%), allowing the discrimination of malignant cases. CONCLUSION: Discrimination using nuclear luminance and steric alterations is useful for morphologically indiscriminable MM cases. Three-dimensional analysis of agglomerates will be further investigated to improve the diagnostic accuracy.

Implications for differential diagnosis of lung cancer-associated lymphadenopathy in lymphoepithelioid cell lymphoma (Lennert's lymphoma) arising simultaneously with lung cancer: a case report.

BACKGROUND: Lymphoepithelioid cell lymphoma (LCL) is a rare morphologic variant of peripheral T-cell lymphoma, and its cytologic features have not been well characterized. We describe details from fine needle aspiration cytology (FNAC) of LCL in a patient simultaneously suffering from lung cancer, in whom extensive lymph node metastasis was suspected clinically. CASE: A 54-year-old man had a lung nodule diagnosed as an adenocarcinoma by biopsy. 18F-fluoro-deoxyglucose positron emission tomography showed high uptake in the lung nodule as well as interlobar, supraclavicular and axillary lymph nodes. FNAC from interlobar and supraclavicular lymph nodes revealed abundant lymphoid cells intermingled with epithelioid cell clusters. Most lymphoid cells were small, with teardrop-shaped nuclei. Occasionally, large lymphoid cells with hyperconvoluted nuclei and prominent nucleoli were observed. An extensive sarcoid reaction was suspected on cytology, and lobectomy was performed. LCL with lung adenocarcinoma was diagnosed on the immunohistochemical findings. CONCLUSION: Detailed observation of lymphoid cells with FNAC is important even in patients with lung cancer and massive regional lymphadenopathy. Presence ofa teardrop nuclear shape and nuclear irregularities of lymphoid cells provides important information for cytologic diagnosis of LCL when epithelioid cell clusters are evident.

Discriminant model for cytologic distinction of large cell neuroendocrine carcinoma from small cell carcinoma of the lung.

BACKGROUND: To establish cytologic criteria for pulmonary large cell neuroendocrine carcinoma (LCNEC), we developed and evaluated a discriminant model for cytologic differential diagnosis between LCNEC and small cell lung carcinoma (SCLC). METHODS: Aspiration cytologic and/or imprint smears from 29 LCNEC cases were reviewed in comparison with 26 SCLC cases. We selected the following parameters for assessment: background, cellular arrangement, cell clusters, cell cohesion, arrangements, cell dimensions areas, the presence of cytoplasm and/or prominent nucleoli, nuclear features, mitosis, naked nuclei, and nuclear streaking. To demonstrate the utility of differences in frequencies of cytologic parameters for LCNECs and SCLCs, a discriminant model was developed and evaluated. RESULTS: Among the cytologic parameters investigated, large clusters (consisting of >or=60 tumor cells) with tight cohesion and small tumor cells (showing

[Simultaneous detection of both non-Hodgkin's lymphoma cells and breast cancer cells in pleural effusion--a case report].

A 55-year-old woman underwent breast-conserving surgery with irradiation for Stage IIB (T2 N1 M0) breast cancer of her right breast. Thereafter, she was treated orally with oral UFT and tamoxifen. Three years following surgery, she was diagnosed as having a non-Hodgkin's lymphoma. She underwent 6 cycles of EPOCH-G (etoposide, vincristine, adriamycin, cyclophosphamide, prednisolone, G-CSF) therapy, and obtained complete remission. Two years later, her neck and inguinal lymph nodes were swollen. Biopsy confirmed the relapse of NHL. She underwent salvage chemotherapies of MST-16, carboplatin, IVAC, and CPT-11, but the disease was refractory. In May 2000, bilateral pleural effusion was detected. Cytomorphologically, the pleural fluid specimen showed both atypical lymphoid cells and adenocarcinoma cells simultaneously. Existence of double cancer in the pleural effusion has not been reported, suggesting that this case is rare.