A Case Report of Superficial Solitary Fibrous Tumor in the Right Parotideomasseteric Region.

Solitary fibrous tumors (SFTs) are rare mesenchymal tumors that occur in various soft tissues and organs throughout the body. Superficial SFTs in the head and neck region are uncommon and reports of such cases are limited. An elderly Japanese woman in her 80s presented to our clinic with a smooth mass in the right parotideomasseteric region. Ultrasonography and magnetic resonance imaging revealed a well-defined subcutaneous mass measuring 20 mm. For a definitive diagnosis and treatment, surgical resection was performed under local anesthesia. Intraoperatively, a brown-colored tumor was identified beneath the skin, without surrounding tissue adhesion, and was completely excised. Immunohistochemistry, revealing the expression of STAT6, confirmed the diagnosis of SFT. Based on the SFT risk classification, this case was classified into the low-risk group, and no recurrence occurred during the 4 year postoperative period. According to the 2020 World Health Organization Classification of Soft Tissue Tumors, SFTs belong to the intermediate category with recurrence potential. In previous studies, cases of positive margins and recurrence have been reported in superficial SFTs, and SFTs may show benign features on clinical presentation but require precise surgical manipulation. Therefore, it is crucial for otolaryngologists to gain a comprehensive understanding of this tumor for appropriate treatment.

Ruptured Saccular Aneurysm Caused by Necrotizing Arteritis of the Polyarteritis Nodosa Type in Primary Angiitis of Central Nervous System.

Primary angiitis of central nervous system (PACNS) is a rare idiopathic vasculitis that typically involves small arteries. An 18-year-old woman was operated on for resection of a ruptured aneurysm in a cerebral artery. Multiple aneurysms of cerebral arteries had been detected by neuroimaging examinations since the age of 12, and she had been administered drugs following a diagnosis of PACNS since the age of 15. The resected aneurysm was a ruptured saccular aneurysm occurring in a medium-sized artery. Histologically, necrotizing arteritis of the polyarteritis nodosa (PAN) type was noted in the aneurysmal wall. It consisted of an admixture of acute and healing stages. In the acute stage, fibrinoid necrosis in the intima and media and intense inflammatory cell infiltrate in the entire wall were present. The inflammatory cells mainly consisted of lymphocytes, including plasma cells, neutrophils, and macrophages. In the healing stage, disappearance of fibrinoid necrosis, fibrosis in the intima and media, and scarce inflammatory cells were noted. The acute stage was mainly present near the ruptured site. From these findings, the aneurysm was considered to have been caused by necrotizing arteritis of the PAN type. Although saccular aneurysmal formation in a medium-sized artery is rare in PACNS, an understanding of aneurysms produced by necrotizing arteritis of the PAN type offers useful information for the diagnosis and treatment of PACNS.

Mixed Mesonephric-like Adenocarcinoma, Clear Cell Carcinoma, and Endometrioid Carcinoma Arising from an Endometriotic Cyst.

Mesonephric-like adenocarcinoma is a rare neoplasm of the uterine corpus and ovary. Unlike prototypical mesonephric adenocarcinoma of the uterine cervix, which is considered of Wolffian origin, recent evidence suggests that mesonephric-like adenocarcinoma is a Mullerian tumor associated with endometriosis. We report here on a 48-year-old woman with a mixed carcinoma of the ovary that consisted of mesonephric-like adenocarcinoma, clear cell carcinoma, and endometrioid carcinoma, arising from an endometriotic cyst. The mesonephric-like adenocarcinoma consisted of cuboidal cells with vesicular nuclei presenting with a tubular, ductal, papillary, and solid architecture forming nodules. Each component showed distinct immunophenotypes that were consistent with their morphology. The mesonephric-like adenocarcinoma showed diffuse positive staining for paired box 8 and GATA binding protein 3, and negative staining for estrogen and progesterone receptors. A p53 stain exhibited wild-type immunoreactivity. A complete loss of AT-rich interactive domain-containing protein 1A (ARID1A) expression was suggestive of an ARID1A mutation. Manual macrodissection and Sanger sequencing revealed identical KRAS and PIK3CA mutations in all three components. To the best of our knowledge, this is the first report of mesonephric-like adenocarcinoma combined with a clear cell carcinoma and endometrioid carcinoma, which supports the hypothesis that mesonephric-like adenocarcinoma is an endometriosis-associated neoplasm. The report also highlights a potential pitfall in diagnosing mesonephric-like adenocarcinoma combined with clear cell carcinoma.

Intraosseous Lipoma of the Calvaria in the Early Stage Resembling Normal Fatty Marrow.

Intraosseous lipoma (IOL) is a benign bone tumor that usually arises from the lower limb and rarely arises from the skull. Radiological diagnosis of a typical case is not problematic due to its characteristic calcification and marginal sclerosis. Here, we report a case of calvarial IOL in the early stage lacking conventional radiopathological features. The patient is a 7-year-old girl who presented with a slow-growing protuberance on the vertex of the head. Computed tomography displayed a low-density mass without calcification that was continuous with the surrounding diploe. The mass was resected piece by piece for diagnostic and cosmetic reasons. Histologically, the specimen consisted of bony trabeculae and intertrabecular adipose tissue, which resembled normal fatty marrow. However, adipose tissue was considered neoplastic since it lacked hematopoietic elements. The final diagnosis of IOL was made by radiopathological correlation. This case suggests that IOL should be included in the differential diagnosis of diploic expansion, even if calcification is absent. The histology of an early-stage IOL resembles normal fatty marrow, but recognizing the absence of hematopoietic elements aids the diagnosis. Also, our literature review indicates that such cases are likely to be encountered in the calvaria than cranial base.

Plasma cell infiltration and treatment effect in breast cancer patients treated with neoadjuvant chemotherapy.

BACKGROUND: Tumour-infiltrating lymphocyte (TIL)-high breast tumours have a high rate of pathological complete response (pCR) with neoadjuvant chemotherapy. In our routine pathological diagnoses of biopsy specimens from pCR cases, we have observed a high infiltration of plasma cells (PCs). A positive correlation of PCs with favourable patient outcome has recently been reported, but little is known about how PCs contribute to local tumour immunity. METHODS: We retrospectively examined biopsy specimens from 146 patients with invasive breast cancer who received neoadjuvant chemotherapy. CD138+ PC infiltration was assessed by immunohistochemistry. Multiplexed fluorescent immunohistochemistry (mfIHC) with T and B cell markers was also conducted to elucidate the profile of immune cells. RESULTS: Greater PC infiltration was observed in the pCR group (p = 0.028) and this trend was confirmed in another patient cohort. With mfIHC, we observed significantly more CD8+, T-bet+CD4+, and CD8+FOXP3+ T cells, total B cells and PCs in pCR cases. Such cases were also characterised by high expression of both PD-1 and PD-L1 on B cells and PCs. In patients with hormone receptor-negative tumours, high PC infiltration was correlated with significantly longer disease-free survival (p = 0.034). CONCLUSIONS: We found that higher PC infiltration in biopsy specimens before neoadjuvant chemotherapy was associated with pCR. With mfIHC, we also revealed that the local cytotoxic immune response was clearly enhanced in pCR cases, as was the infiltration of B cells including PCs. Moreover, higher PC levels were correlated with favourable outcomes in hormone receptor-negative breast cancer patients.

A collision tumor of solitary fibrous tumor/hemangiopericytoma and meningioma: A case report with literature review.

An intracranial collision tumor is a rare lesion composed of two histologically different neoplasms in the same anatomic location. Even more rare is the collision tumor of a solitary fibrous tumor/hemangiopericytoma (SFT/HPC) and meningioma. The patient was a 46-year-old woman who had a 40 × 35 × 30-mm mass in the vermis of the cerebellum. Histologically, the mass consisted of two different components. One component showed the morphology of meningioma (World Health Organization (WHO) grade I), and the other component exhibited small round cell proliferation with hypercellular density, which was revealed to be SFT/HPC (WHO grade III) based on STAT6 immunohistochemistry. STAT6 showed completely different immunohistochemistry results in these two components (nuclear-negative in meningioma and nuclear-positive in SFT/HPC). Since these two neoplasms are associated with different prognoses, they should be distinguished from each other. When meningioma and an SFT/HPC-like lesion are identified morphologically, it is important to recognize the presence of such a collision tumor composed of meningioma and SFT/HPC, and identify the SFT/HPC component by employing STAT6 immunohistochemistry.

Dysgerminoma with Estrogen-Producing Functioning Stroma Presenting Precocious Puberty.

Dysgerminoma is a malignant ovarian germ cell tumor, and unlike sex-cord stromal tumors, endocrine manifestation is considered rare. Here, we report the first case of dysgerminoma presenting precocious puberty. The patient is a 7-year-old girl who presented with a breast development in Tanner stage 3. Serum estradiol (E2) was markedly elevated while luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were suppressed below the detection limit. Microscopically, the right ovarian mass displayed nests of large polygonal cells and fibrous septa which were focally concentrated by theca-like plump spindle cells. Immunohistochemistry revealed that the spindle cells expressed various steroidogenic enzymes involved in estrogen biosynthesis including P450 aromatase. The tumor was diagnosed with pure dysgerminoma with estrogen-producing functioning stroma. After the operation, serum E2 declined below the detection limit; LH and FSH returned within the normal range. This case demonstrates that even a conventional dysgerminoma can present endocrine manifestation through functioning stroma.

Molecular and clinicopathological features of appendiceal mucinous neoplasms.

Appendiceal mucinous tumors (AMTs) include low-grade mucinous appendiceal neoplasms (LAMNs), high-grade mucinous appendiceal neoplasms (HAMNs), and mucinous adenocarcinomas (MACs). We collected 51 AMT samples (LAMN: 34, HAMN: 8, MAC: 9). Three of the eight HAMN cases contained LAMN components, and four out of nine MAC cases contained LAMN and/or HAMN components within the tumor. A next-generation sequencing (NGS) cancer hotspot panel was used to analyze 11 pure LAMN, 4 HAMN, and 3 MAC cases. The results revealed KRAS and GNAS as the most frequently mutated genes. Sanger sequencing was then performed to detect KRAS, GNAS, and TP53 mutations in the remaining 31 cases and RNF43 mutations in all cases. KRAS/GNAS and TP53 mutations occurred exclusively in pure LAMNs; however, five LAMN cases had mutations in both KRAS and GNAS. RNF43 mutations almost exclusively occurred with KRAS/GNAS mutations in pure LAMNs. In MAC and HAMN, KRAS/GNAS mutation status was nearly preserved between lower-grade areas. Most of the detected RNF43 mutations was missense type. RNF43 mutations were detected in both components of MAC with lower-grade area; however, RNF43 mutations detected in these two lesions were entirely different. RNF43 mutations were detected in only one of the eight HAMN patients, which was the sole case without pseudomyxoma peritonei (PMP). None of the four MAC patients with RNF43 mutation showed PMP. These findings suggest that RNF43 mutations occur at a later stage of MAC development and do not associate with PMP. Furthermore, a gradual transition from LAMN to MAC via HAMN could be considered.

Antitumor effects of novel mAbs against cationic amino acid transporter 1 (CAT1) on human CRC with amplified CAT1 gene.

Copy number alterations detected by comparative genomic hybridization (CGH) can lead to the identification of novel cancer-related genes. We analyzed chromosomal aberrations in a set of 100 human primary colorectal cancers (CRCs) using CGH and found a solute carrier (SLC) 7A1 gene, which encodes cationic amino acid transporter 1 (CAT1) with 14 putative transmembrane domains, in a chromosome region (13q12.3) with a high frequency of gene amplifications. SLC7A1/CAT1 is a transporter responsible for the uptake of cationic amino acids (arginine, lysine, and ornithine) essential for cellular growth. Microarray and PCR analyses have revealed that mRNA transcribed from CAT1 is overexpressed in more than 70% of human CRC samples, and RNA interference-mediated knockdown of CAT1 inhibited the cell growth of CRCs. Rats were immunized with rat hepatoma cells expressing CAT1 tagged with green fluorescent protein (GFP), and rat splenocytes were fused with mouse myeloma cells. Five rat monoclonal antibodies (mAbs) (CA1 ~ CA5) reacting with HEK293 cells expressing CAT1-GFP in a GFP expression-dependent manner were selected from established hybridoma clones. Novel anti-CAT1 mAbs selectively reacted with human CRC tumor tissues compared with adjacent normal tissues according to immuno-histochemical staining and bound strongly to numerous human cancer cell lines by flow cytometry. Anti-CAT1 mAbs exhibited internalization activity, antibody-dependent cellular cytotoxicity, and migration inhibition activity against CRC cell lines. Furthermore, CA2 inhibited the in vivo growth of human HT29 and SW-C4 CRC tumors in nude mice. This study suggested CAT1 to be a promising target for mAb therapy against CRCs.

Late recurrence of a papillary thyroid carcinoma 37 years after hemithyroidectomy: Solitary, left cervical lymph node metastasis evident on fluorodeoxyglucose positron-emission tomography/computed tomography images revealing nodular uptake.

In patients with well-differentiated papillary thyroid carcinoma (PTC), late recurrence is very rare. It is unusual that 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (PET/CT) shows hypermetabolic lesions in patients with well-differentiated PTC metastases. We demonstrate an exceptional case exhibiting a first relapse 37 years after hemithyroidectomy to treat PTC. Recurrent metastasis of a PTC should be considered as a differential diagnosis even if the elapsed time from the initial treatment is great. A left cervical lymphadenopathy, which exceptionally exhibited a hypermetabolic lesion on PET/CT, should be considered a metastatically well-differentiated PTC.

Hydrocele of the Canal of Nuck with Endometriosis: Right-Side Dominance Confirmed by Literature Review and Statistical Analysis.

Introduction. The canal of Nuck is an embryological remnant of the peritoneal pouch that extends into the labium majus of women. Hydrocele is the most common presentation, but only a small number of cases are reported in association with endometriosis. Case Presentation. The patient is a 45-year-old woman who presented with left inguinal mass with persistent pain. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a 30 mm cystic mass, and a hydrocele of the canal of Nuck (HCN) was suspected. The excised mass was a cyst containing yellow-tan serous fluid, and the cyst wall was lined by mesothelium. The morphology was consistent with conventional HCN. However, since several foci of endometrial-like epithelium and stroma were identified beneath the mesothelium, the mass was diagnosed with HCN with endometriosis (EM-HCN). Discussion. Right-side dominance of EM-HCN is suggested by several authors, but a thorough review has never been performed. For the first time, we reviewed the literature and statistically confirmed that EM-HCNs dominantly occur on the right side compared to those without endometriosis. We consider that this supports the theory that endometriosis derives from retrograde menstruation of endometrial tissue through fallopian tubes. When endometriosis is discovered in HCN, the clinician should be aware of the possibility of pelvic endometriosis.

Intravascular ultrasound imaging of isolated and non aorto-ostial coronary Takayasu arteritis: a case report.

BACKGROUND: Isolated coronary Takayasu arteritis is a rare form of ischemic heart disease that typically appears as an aorto-ostial lesion. Although several vascular imaging modalities including ultrasonography, computed tomographic angiography, magnetic resonance angiography or catheter angiography, play crucial roles for diagnosing Takayasu arteritis, the intravascular ultrasound imaging of Takayasu arteritis is not well studied. CASE PRESENTATION: A 55-year-old woman who was diagnosed with heterozygous familial hypercholesterolemia underwent coronary angiography due to effort angina, which showed ostial left anterior descending coronary artery (LAD) stenosis. Although directional coronary atherectomy followed by drug-coated balloon was successfully performed, 6 months later restenosis occurred at the ostial LAD, and the ostial left circumflex coronary artery (LCx) progressed significantly. The intravascular ultrasound imaging in these lesions was noteworthy, in which the media was partly unrecognizable and an echo intensity similar to fibrotic intimal thickening traversed from the intima to the adventitia, thereby causing the whole image of the coronary artery to become unclear. Directional coronary atherectomy followed by drug-coated balloon procedures for both LAD and LCx lesions were performed again. Systemic examination of computed tomographic angiography found no other stenotic lesions except for those in the coronary arteries. Five months later, the LAD and LCx lesions progressed diffusely, therefore the coronary artery bypass graft was done. The histopathological findings of specimens of the coronary artery that were obtained during the bypass graft showed excessive fibrous thickening of the intima and adventitia, with granulomatous inflammation in the media, which led to the diagnosis of isolated coronary Takayasu arteritis. Systemic corticosteroid therapy was then started. CONCLUSIONS: We described an extremely rare case of isolated and non aorto-ostial Takayasu arteritis. The characteristic intravascular ultrasound images of diseased coronary arteries may help in the diagnosis of coronary Takayasu arteritis.

A unique autopsy case of ascending aortic dissection caused by giant cell arteritis without drug therapy.

Giant cell arteritis is a granulomatous inflammation of large and medium-sized arteries, occurring predominantly in older women. In this case, a 76-year-old woman was hospitalized for examination because of a high C-reactive protein (CRP) level, but nothing remarkable was found on thoracicoabdominal computed tomography (CT) or head magnetic resonanse imaging (MRI). On the 46th day from the first visit, she died suddenly due to cardiac tamponade. On pathological autopsy, we found the cause of death to be acute aortic dissection (Stanford type A) due to giant cell arteritis occurred in the ascending aorta. Histologically, granulomatous vasculitis with giant cells was recognized in the ascending aorta, thoracic descending aorta and abdominal aorta and their branches. Interestingly, similar granulomatous vasculitis was also found in the medium and small vessels of other plural organs, including the heart, liver, uterine corpus, and its appendages. To our knowledge, giant cell arteritis with multiple-organ granulomatous changes has not been reported before. We herein reported a unique autopsy case of giant cell arteritis in a patient not treated with medication.

Diagnosis and Treatment of Early-Stage Glioblastoma.

Early-stage glioblastoma has few identifiable findings; clinical significance of its early diagnosis and treatment remains unclear as no report has described treatment and long-term follow-up for early-stage glioblastoma. Here, we report a case of a 69-year-old woman with early-stage glioblastoma treated by microsurgical resection and chemoradiotherapy. Magnetic resonance imaging (MRI) revealed a small high-intensity lesion in the right temporal lobe on T2-weighted imaging. Contrast-enhanced T1-weighted MRI revealed ring enhancement. On magnetic resonance spectroscopy, the lesion demonstrated increased choline and reduced N-acetyl-aspartate levels compared with the normal brain. Positron emission tomography with 11C-methionine (MET) revealed 11C-methionine uptake in the lesion. Microsurgical resection was performed, and glioblastoma was pathologically diagnosed. The patient was treated with local radiotherapy and temozolomide chemotherapy postoperatively. Eight years postoperatively, the patient is surviving without tumor recurrence, but progressive cognitive impairment developed 6 years' postoperatively. Aggressive treatment of early-stage glioblastoma may improve its extremely poor prognosis. Conversely, cognitive impairment may become a significant medical and social problem when effective therapies for glioblastoma are developed.

Hepatic Sclerosing Hemangioma with Predominance of the Sclerosed Area Mimicking a Biliary Cystadenocarcinoma.

We report here an extremely rare case of hepatic sclerosing hemangioma mimicking a biliary cystadenocarcinoma. A previously healthy 39-year-old woman was referred to our hospital because of a large tumor in the liver. Abdominal computed tomography revealed early peripheral ring enhancement in the arterial phase and slight internal heterogeneous enhancement in the delayed phase. Magnetic resonance imaging revealed a tumor with low intensity in the T1-weighted image and very high intensity in the fat-saturated T2-weighted image. The patient underwent hepatectomy for a possible malignant liver tumor. Grossly, the tumor appeared as a white, solid, and cystic mass (weighted 1.1 kg and measured 170×100×80 mm) that was elastic, soft, and homogeneous with a yellowish area. Histological examination showed that the tumor mostly consisted of fibrotic areas with hyalinization. The typical histology of cavernous hemangioma was confirmed in part, and the tumor was diagnosed as a sclerosing hemangioma with predominancy of the sclerosed area. A review of 20 cases reported previously revealed that only 2 (10%) patients were diagnosed as having sclerosing hemangioma preoperatively.

Coexistence of Cervical Leiomyosarcoma and Gastric-Type Adenocarcinoma In Situ with Extensive Extension to the Endometrium and Fallopian Tube.

Cervical leiomyosarcoma is known to be rare from the previous reviews of a large number of malignant cervical tumors. The patient was a 66-year-old woman with irregular vaginal bleeding. She underwent modified radical hysterectomy and bilateral salpingooophorectomy. Histopathologically, we diagnosed the coexistence of uterine cervical leiomyosarcoma and cervical gastric-type adenocarcinoma in situ with endometrial lesions that had continuous and skip patterns and fallopian tubal lesions with a partial lesion. To the best of our knowledge, cases of synchronous leiomyosarcoma and cancers have not often been reported; only two cases of synchronous cervical leiomyosarcoma and cervical squamous cell carcinoma have been published. This case is the first presentation of coincidental primary cervical leiomyosarcoma and cervical gastric-type adenocarcinoma in situ. Additionally, we considered cervical gastric-type adenocarcinoma in situ with continuous lesions on the endometrium and skip lesions on the left fallopian tube.

Low-grade intraductal carcinoma of the salivary gland with prominent oncocytic change: a newly described variant.

AIMS: Low-grade intraductal carcinoma (LG-IDC) is a clinically indolent malignant tumour of the salivary glands. Because of its rarity, the histological variants of LG-IDC have not been well characterised. Herein, we describe five LG-IDC cases with prominent oncocytic change in the major salivary glands. METHODS AND RESULTS: We examined five cases, three males and two females (mean age = 63 years), of LG-IDC with oncocytic change. The sites affected by LG-IDC were the parotid and submandibular glands. The lesions were macroscopically unilocular or multilocular cysts with a solid tumour arising from the cyst wall. Smaller tumour cell nests were also observed. As with classic LG-IDC, the cyst wall was surrounded by myoepithelial cells with no invasive component. The tumour cells had abundant oncocytic cytoplasm and proliferated in a low-papillary, tubular or cribriform pattern. Immunohistochemically, the tumour cells were diffusely positive for pan-cytokeratin, S100, mammaglobin and antimitochondria antibody, and were negative for androgen receptor and gross cystic disease fluid protein-15. Unlike classic LG-IDC, some of these cases demonstrated focal invagination of myoepithelial cells in the intraductal tumour. CONCLUSION: Oncocytic LG-IDC should be recognised as a histologically unique variant of LG-IDC. Awareness of this entity is important to avoid erroneous diagnosis and inappropriate treatment for histological mimics.

Useful aspects of diagnosis of imprint cytology in intraoperative consultation of ovarian tumors: comparison between imprint cytology and frozen sections.

BACKGROUND: In the intraoperative consultation of ovarian tumors, the histological diagnosis of frozen sections (FS) of large tumors is frequently difficult because of the limited number of tumor samples. The application of imprint cytology (IC), in which samples are obtained from wide areas of the tumors, is useful for intraoperative consultation. However, the useful aspects of IC have not been clearly defined. The present study is a detailed comparison of IC and FS that clearly defines the useful aspects of IC. METHODS: Fifty-five cases of ovarian tumors that were examined using both IC and FS were evaluated. The histological diagnoses consisted of benign (16), borderline (6), and malignancy (33). All of the malignant tumors consisted of various types of carcinoma. RESULTS: Benignity and malignancy were accurately diagnosed by both IC and FS. In the borderline group, the diagnostic accuracy of IC was very low (1/6: 16.6%) compared with FS (4/6: 66.6%). The diagnostic accuracy including benign, borderline, and malignant groups was 90.9% (50/55) for IC and 96.3% (53/55) for FS. Concerning the diagnosis of the types of carcinoma, the overall diagnostic accuracy of IC (25/31: 80.6%) was greater than that of FS (21/31: 67.7%), especially for the diagnosis of clear cell carcinoma (IC, 100%; FS, 80%) and mixed carcinoma (IC, 66.6%; FS, 16.6%). CONCLUSION: The useful aspects of IC in the intraoperative consultation are the diagnosis of benignity or malignancy and the accuracy of diagnosing clear cell carcinoma and mixed carcinoma.

Cystic Endometrioma with Coexisting Fibroma Originating in a Supernumerary Ovary in the Rectovaginal Pouch.

A supernumerary ovary is an exceedingly rare disorder, in which the structure containing ovarian tissue is located at some distance from the normally placed ovary. 16 cases of endometriosis or tumors originating in a supernumerary ovary have been published in the English literature, but no case of coexisting endometriosis and a tumor has been published. We present the case of a 40-year-old female with cystic endometrioma with coexisting fibroma originating in a supernumerary ovary in the rectovaginal pouch. The present case is the first to be reported with coexisting endometriosis and a tumor originating in a supernumerary ovary. Our experience with this case and the results of our previous studies of rectovaginal endometriosis indicated that the possibility of originating in a supernumerary ovary shall be examined in cases of cystic endometrioma in the rectovaginal pouch.

Application of Returned Cell Block Method (Cell Block from a Papanicolaou Staining Smear on a Glass Slide) for the Evaluation of Fine Needle Aspiration Cytology of Tumors of the Breast.

BACKGROUND: In the fine needle aspiration cytology (FNAC) for tumors of the breast, evaluation is frequently difficult because of the thick-layered cell clusters and blood inclusion. Such problems may be resolved by the returned cell block method, but its use has not spread worldwide. Here, we examined the application of the returned cell block method to cases involving difficulty in the evaluation of FNAC to diagnose tumors of the breast. METHODS: In Juntendo University Nerima Hospital, there were 22 cases which were difficult to diagnose by Papanicolaou stain only, and they underwent additional examination using the returned cell block method (cell block from a Papanicolaou staining smear on a glass slide). The usefulness of the returned cell block method in these cases was examined. RESULTS: Among the 22 cases, a correct diagnosis was facilitated in 20 cases using the returned cell block method. In 16 of the 20 cases, the difficulty in FNAC was because of thick-layered cell clusters (12 cases) and blood inclusion (four cases). Among the 12 cases with difficulty because of the thick-layered cell clusters, 10 cases (83%) comprised intraductal papilloma (six cases) and intraductal papillary carcinoma (four cases). Papilloma and papillary carcinoma were correctly diagnosed by the addition of histological images and immunostaining of myoepithelial cells using the returned cell block method. CONCLUSION: The application of the returned cell block method is useful for precise evaluation of the cytological diagnosis of tumors of the breast, especially papillary lesions. Diagn. Cytopathol. 2016;44:505-511. © 2016 The Authors Diagnostic Cytopathology Published by Wiley Periodicals, Inc.