Basaloid squamous cell carcinoma with adenoid cystic-like features of the head and neck region: A report of two cases.

The histology of basaloid squamous cell carcinoma (BSCC) can resemble that of adenoid cystic carcinoma (AdCC). Herein, we report two cases of BSCC with adenoid cystic-like features (BSCC-AdC). We collected cases of AdCC and BSCC of the head and neck region, extracted two cases with unusual histology, and reexamined them histologically and immunohistochemically. Case 1 involved an 81-year-old Japanese male, who had an elastic-hard mass on the left side of his tongue, and a biopsy examination suggested AdCC. Case 2 involved a 63-year-old Japanese male, who had a polypoid mass on his right hypopharynx. He was diagnosed with AdCC with high-grade transformation. Histologically, atypical cells in a myxoid stroma, which exhibited trabecular, nest-like, and/or cribriform growth patterns, and necrosis were observed in both cases. Case 2 displayed more marked cellular atypia than Case 1. Immunohistochemically, the tumor cells were diffusely positive for cytokeratin 5/6, p63/p40, SRY-related HMG-box 10 and Ki-67, but negative for other myoepithelial markers and p16. Finally, both cases were rediagnosed as BSCC-AdC. It is known that esophageal BSCC displays adenoid cystic-like features, and BSCC-AdC also sometimes occurs in the head and neck region. Clinicians should carefully differentiate BSCC-AdC from AdCC of the minor salivary glands and human papillomavirus-related carcinoma.

Ontogenic development of nerve fibers in human fetal livers: an immunohistochemical study using neural cell adhesion molecule (NCAM) and neuron-specific enolase (NSE).

The aim of the study was to investigate nerve fibers (NF) in human fetal livers. An immunohistochemical study was performed. NF were classified into portal tract innervation (PoI) and parenchymal innervation (PaI). The hilum area showed many Pol NF at 7 GW, and NF increased with gestational week (GW). Direct innervations to biliary epithelium were recognized. In large portal tracts, a few NCAM-positive mesenchymal cells were seen at 8 GW and many mesenchymal cells were noted around 12 GW. Apparent NF emerged around 15 GW, and NF increased with GW. Many NF plexuses were seen in 30-40 GW. In small portal tracts, no NF were seen in 7-10 GW. A few NCAM-positive mesenchymal cells emerged in 11 GW, and they increased thereafter. Apparent NF were seen around 20 GW and NF increased with GW. At term (40 GW), PoI NF were still immature. Ductal plate (DP) was positive for NCAM, NSE, chromogranin and synaptophysin, and direct innervations to DP were seen. The direct innervations to developing bile ducts and peribiliary glands were also seen. PaI NF were first seen at 21 GW and was consistent until 40 GW in which a few NF were seen in PaI. These observations suggest that PoI NF arise from committed portal mesenchyme. PaI NF are very immature at 40 GW. There are direct innervations to bile ducts, peribiliary glands, portal veins, hepatic arteries, and DP.

Decidualization of uterine adenomyoma in a pregnant woman: a case report with immunohistochemical study.

BACKGROUND: Decidualization of uterine adenomyoma has not been reported, to the best of the author's knowledge. AIM: To report a case of uterine adenomyoma with decidualization. CASE REPORT: A 43-year-old pregnant woman with "myoma" underwent cesarean operation and "myomectomy" at 37 gestation weeks. The operation was successful, and the baby and mother were healthy. Grossly, the "myoma" measured 12 × 10 × 10 cm, and the consistency was firm. Microscopically, the tumor was adenomyoma consisting of smooth muscle bundles and endometrial islands. Characteristically, the endometrial stroma showed marked decidualization. An immunohistochemical study showed that the decidual cells were positive for pancytokeratin AE1/3, pancytokeratin CAM5.2, cytokeratin (CK)7, CK18, vimentin, CA125, CD10, estrogen receptor (ER), progesterone receptor (PgR), and Ki-67 (labeling 1 %). They were negative for CK34ßE12, CK5/6, CK8, CK14, CK19, CK20, EMA, p63, desmin, α-smooth muscle actin, S100 protein, CK34, CD68, and p53. These results show that marked decidualization occurs in adenomyoma during pregnancy, and that the decidual cells are positive for pancytokeratin AE1/3, pancytokeratin CAM5.2, CK7, CK18, vimentin, CA125, CD10, ER, and PgR. CONCLUSION: A rare case of uterine adenomyoma with decidualization is reported.

Primary small cell carcinoma of prostate without immunoreactive neuroendocrine proteins but with expressions of KIT and platelet-derived growth factor-α.

Primary small cell carcinoma of the prostate is extremely rare. Herein reported is a case of primary small cell carcinoma of the prostate with immunohistochemical examination of KIT and platelet-derived growth factor-α. The present case is unique in that the small cell carcinoma did not express neuroendocrine antigens. A 68-year-old man was found to have high serum prostate-specific antigen, and biopsy showed malignant small tumor cells fulfilling the small cell carcinoma criteria of the World Health Organization. Immunohistochemically, tumor cells were positive for pan-cytokeratin, KIT, platelet-derived growth factor-α, p53, Ki-67 labeling = 65%, prostate-specific antigen and alpha-methylacyl-CoA racemase. Tumor cells were negative for vimentin, CD56, synaptophysin, chromogranin and neuron-specific enolase. Imaging modalities showed multiple metastases, and the patient was treated by chemotherapy. The present report is the fifth with immunohistochemistry of prostatic small cell carcinoma.

Malignant glomus tumor of the foot with obvious neuroendocrine differentiation: a case report with immunohistochemical studies.

Obvious neuroendocrine differentiation has not been reported in glomus tumor. The author herein reports a malignant glomus tumor of the foot showing obvious neuroendocrine differentiation. A 63-year-old woman presented with tumor of the left foot. The tumor was superficially seated, and located in the dermis. It was completely resected with wide margins. It measured 0.7 × 0.7 × 0.6 cm. Microscopically, the tumor was composed of atypical epithelioid cells located around blood vessel-like structures. The epithelioid cells showed relatively clear cytoplasm and severe cellular atypia, and resembled basal cell carcinoma. Focal areas of squamoid differentiation, carcinoid patterns, and neural differentiations were seen. There was no necrosis or atypical mitosis. However, mitotic figures were seen in 16 per 50 high-power-fields (HPF). The hematoxylin and eosin (HE) diagnosis was basosquamous carcinoma. Immunohistochemically, the tumor cells were strongly positive for vimentin, -smooth muscle actin, and neuron-specific enolase. The tumor was focally positive for NCAM, synaptophysin and chromogranin. The blood vessel-like structures had a layer of CD31- and CD34-positive endothelial cells. Tp53 was positive and the Ki-67 labeling index was 23%. The tumor cells were negative for cytokeratin (CK) AE1/3, CK CAM5.2, CK5, CK6, CK7, CK8, CK14, CK18, CK19, CK20, p63, EMA, CEA, CA19-9, desmin, myoglobin, HMB-45, Melan-A, S100 protein, MUC1, MUC2, MUC5AC, and MUC6. Taken together with HE histology, the tumor was labeled as malignant glomus tumor with neuronal differentiation, based on the classification system of Folpe et al. The post-pathological diagnosis whole body examination using CT, MRI, PET, and endoscopies identified no tumors. The patient is now free from tumor and healthy 18 months after the resection.

Small cell neuroendocrine carcinoma of the prostate: incidence and a report of four cases with an examination of KIT and PDGFRA.

Because there have been no reports on the incidence and expressions and mutations of KIT and PDGFRA in small cell neuroendocrine carcinoma (SCNEC) of the prostate, the author surveyed archival specimens of 2,642 prostatic specimens (biopsy, 1,503 cases; transurethral resection, 1,009 cases; prostatectomy, 130 cases). Of these, 706 cases were malignant tumors. In equivocal cases (n = 16) of Gleason 5 adenocarcinoma resembling SCNEC, several neuroendocrine markers were immunohistochemically examined. As the results, four cases of SCNEC were identified; therefore the incidence of SCNEC was 0.5% of all prostatic malignancies. All the four cases were biopsies. The remaining 686 cases were adenocarcinomas. In case 1 (50 years of age), the SCNEC tumor cells were positive for cytokeratin, P504S, synaptophysin, KIT, and PDGFRA, but negative for PSA, neuron specific enolase, CD56, and TTF-1. In case 2 (70 years of age), the tumor cells were positive for cytokeratin, PSA, P504S, chromogranin, and synaptophysin, but negative for neuron-specific enolase, CD56, TTF-1, KIT, and PDGFRA. In case 3 (72 years of age), the SCNEC tumor cells were positive for cytokeratin, PSA, P504S, synaptophysin, CD56, KIT, and PDGFRA, but negative for neuron-specific enolase, chromogranin, and TTF-1. In case 4 (81 years of age), the SCNEC tumor cell were positive for cytokeratin, PSA, P504S, chromogranin, synaptophysin, neuron-specific enolase, KIT, and PDGFRA, but negative for CD56 and TTF-1. A molecular genetic analysis using PCR-direct sequencing showed no mutations of KIT (exons 9, 11, 13, and 17) and PDGFRA (exons 12 and 18) genes in three informative cases of SCNEC. The present cases were the first of prostatic SCNEC with an examination of KIT and PDGFRA expression and KIT and PDFGRA gene mutations.

Malignant transformation of exophytic Schneiderian papilloma of the nasal cavity.

Schneiderian papilloma (SP) is classified into three types: inverted, oncocytic, and exophytic. Malignant transformation occurs in 10% of SP; most are inverted and oncocytic types. Malignant transformation of polypoid exophytic SP is exceptional; only two cases have been reported in the English literature. A 58-year-old man consulted our hospital because of nasal obstruction. Nasal endoscopy and imaging modalities showed a polyp in the right nasal cavity. Biopsy findings showed compatibility with SP. However, since fludeoxyglucose positron emission tomography (FDG-PET) showed signals, polypectomy was performed. Grossly, the polyp was reddish white and measured 2 cm. Histologically, the polyp consisted of a non-invasive squamous cell carcinoma (SCC) component (70%), a mature squamous component (20%), and Schneiderian epithelium (10%). Vague koilocytosis was present in the SCC component. The three components were arranged in an exophytic papillary pattern. Immunohistochemically, the non-invasive SCC component was positive for cytokeratins (AE1/3, CAM5.2, CK5/6), p63, p53, and Ki67 (labeling 50%). The mature squamous component was positive for cytokeratins (AE1/3, CAM5.2 and CK5/6), p63, and Ki67 (labeling 6%). The Schneiderian component was positive for cytokeratins (AE1/3, CAM5.2, and CK5/6), p63, and Ki-67 (labeling 4%). The tumor was HPV negative in the three components. The polyp was diagnosed as exophytic Schneiderian carcinoma arising from exophytic SP. The patient is now free from tumor 4 years after the operation.

Sinonasal-type hemangiopericytoma of the nasal cavity and paranasal sinus.

Sinonasal-type hemangiopericytoma is a very rare disease. A 64-year-old man was admitted to our hospital because of nasal obstruction. Nasal endoscopy showed a polyp in the right nasal cavity. Imaging modalities including CT and MRI revealed polypoid tumors in the right nasal cavity and right sphenoid sinus. Excision of the tumors was performed. Macroscopically, the nasal tumor was reddish and focally cystic, and the tumor of the sphenoid sinus was reddish and solid. Microscopically, round and polygonal cells were seen to proliferate monotonously in a medullary fashion. Each tumor cell had a vesicular nucleus and amphophilic cytoplasm. The cellularity was high and mitotic figures were recognized in 6 per 10 high-power fields. Many thin-walled vessels were embedded within the tumor. No collagenization was recognized. A silver stain showed that fine argyrophilic fibers encased individual cells and a few cell nests. Mild invasion into the surrounding tissue was recognized in focal areas. The tumor showed focal cystic and hemorrhagic changes. Immunohistochemically, the tumor cells were positive for vimentin, bcl-2 and factor XIIIa, and negative for cytokeratins, epithelial membrane antigen, CD34, desmin, α-smooth muscle antigen, myoglobin, myogenin, CD31, KIT, p53 protein, CD99, and factor VIII-related antigen. Ki-67 labeling was 17%. The pathological diagnosis was low-grade malignant sinonasal-type hemangiopericytoma. The patient was followed up, but no recurrence has been seen 4 years after the operation.

Clear cell adenocarcinoma of the ovary arising in atypical endometriosis: a report of eight cases.

INTRODUCTION: Studies of clear cell adenocarcinoma of the ovary (CCAO) arising from endometriosis are scant. MATERIALS AND METHODS: The author reviewed 13 cases CCAO of our pathology laboratory for the presence of endometriosis within the tumor. Eight (61.5%) of the 13 tumors contained endometriosis within the tumor. Of the eight cases, seven were atypical endometriosis and one was ordinary endometriosis. The age of the eight patients with CCAO ranged from 35 to 82 years with a median of 52 years. RESULTS: Grossly, the ovarian tumors of CCAO were characterized by unilocular cystic lesions containing solitary or multiple nodules in the inner surfaces. The outer surface was smooth and free of tumor. Histologically, the nodules showed typical features of pure CCAO with clear cells, hobnail cells, and hyalinized stroma. The non-nodular flat areas of the tumor were composed of a layer of atypical clear cells and endometriosis consisting of a layer of endometrial epithelium and endometrial stroma. Incipient foci of CCAO were occasionally recognized in the atypical clear cells. Seven cases with endometriosis showed atypia of the endometrial epithelium (atypical endometroiosis), and one case showed no atypia. There was contiguity between the CCAO and atypical clear cells and between atypical clear cells and endometriosis. Contiguity between atypical endometriosis and CCAO was also recognized in a few areas. The outer surface was devoid of tumor cells and endometriosis. CONCLUSIONS: The author speculates as follows. An endometrial cyst develops in the ovary. Its epithelium undergoes initiation, thus giving rise to atypical endometriosis consisting of dysplastic or intraepithelial neoplastic epithelium. The atypical endometriosis further undergoes initiation, leading to the atypical clear cells, and ultimately leads to CCAO showing a unilocular cyst consisting of inner masses of CCAO and flat areas composed of a layer of atypical clear cells with incipient CCAO and atypical endometriosis.

Serous papillary adenocarcinoma probably arising from epithelial inclusions of the hepatic hilar lymph node.

BACKGROUND: Only three cases of serous adenocarcinoma arising from Mullerian epithelial inclusions of the lymph node have been reported. Herein reported is a case of serous papillary adenocarcinoma arising probably from epithelial (Mullerian) inclusions of the hepatic hilar lymph node. CASE REPORT: A 73-year-old woman presented with peripheral neuropathy, which was thought to be a paraneoplastic syndrome associated with visceral malignancy. Total body examination, including X-P, US, CT, MRI, PET, and upper and lower gastrointestinal endoscopy was done. As the results, only lymph node swelling was detected in the hepatic hilus. Tumor was not identified in other sites. The physicians considered malignant lymphoma, and laparotomic excision of the hepatic hilar mass was performed. Cytological examination of abdominal cavity washing revealed no malignant cells. Grossly, the mass was firm and white and measured 4 × 5 × 5 cm. Microscopically, the mass showed carcinoma cells arranged in papillary and tubular patterns. The appearances strongly resembled serous papillary adenocarcinoma of the ovary. Lymph node structures were noted in some peripheral areas. No benign epithelial inclusions were recognized. Immunohistochemically, the carcinoma cells were positive for ER, PgR, CA125, WT1, p53. They were negative for TTF-1 and CDX-2. Because the positive ER, PgR, CA125, WT1, p53 and p16 are indicative of gynecologic malignancy, simple hysterectomy and bilateral salpingo-oophorectomy were performed, which showed no abnormalities. Cytological examination of abdominal cavity washing fluid revealed no malignant cells. The patient was treated by paclitaxel and carboplatin, and is now alive without metastasis 2 years after the first manifestation. CONCLUSION: The author reported a case of serous papillary adenocarcinoma arising probably from epithelial (Mullerian) inclusions of the hepatic hilar lymph node.