Esophageal squamous cell carcinoma characterized by extensive chondroid differentiation

Chondrosarcoma-like metastasis from a poorly differentiated uterine cervical squamous cell carcinoma. A unique morphology and diagnostic pitfall in cytology

Rare cases of metastatic squamous cell carcinoma with chondroid differentiation from esophageal primary have been reported but none from the uterine cervix. Given the rarity of this phenomenon and potential diagnostic pitfall, we present this unusual case. The patient is a 25-year-old woman who presented with shortness of breath. Computerized tomography (CT) showed several lung and pleural-based nodules. CT-guided core biopsy with touch preparations were performed on the pleural-based nodule. The touch preparations showed large, spindle-to-oval shaped cells with pleomorphic nuclei embedded in metachromatic chondroid stroma. The core biopsies also showed predominantly round-to-spindle shaped cells with hyperchromatic nuclei and prominent nucleoli embedded in a cartilaginous matrix. Her past medical history is significant for a poorly differentiated squamous cell carcinoma of the cervix, which on review showed a typical non-keratinizing squamous cell carcinoma without sarcomatous differentiation. Immunohistochemical stains performed on the pleural-based mass showed tumor positivity for AE1/AE3, CK5/6, p16, and S-100. Similar results were seen when the cervical tumor was stained retrospectively. Human papilloma virus (HPV) in situ hybridization performed on both the pleural-based mass and cervical tumor detected the presence of high-risk HPV subtypes including 16 and 18. These findings supported a lung metastasis from the prior cervical carcinoma. This case emphasizes that cervical carcinoma can develop mesenchymal (chondrosarcomatous) differentiation in metastasis even in tumors presenting with pure epithelial phenotype. Awareness of this occurrence especially on limited cytology material, knowledge of the prior history and use of ancillary tests are extremely helpful in arriving at the correct diagnosis. Diagn. Cytopathol. 2017;45:750-753. © 2017 Wiley Periodicals, Inc.

Expression of Bone Morphogenetic Protein-6 and Bone Morphogenetic Protein Receptors in Myoepithelial Cells of Canine Mammary Gland Tumors

To study the ectopic chondrogenesis in canine mammary mixed tumors, the expression of bone morphogenetic protein-6 (BMP-6) and specific BMP receptors (BMPRs), BMPR-IA, BMPR-IB, and BMPR-II, was examined using immunohistochemical and immunoblot analysis in 39 canine mammary gland tumors. Immunohistochemically, BMP-6 and all three types of BMPRs were coexpressed in the myoepithelial cells and chondrocytes in six of eight benign mixed tumors. In complex adenomas, myoepithelial cells showed an expression pattern of BMP-6, BMPR-IA, and BMPR-II similar to those in benign mixed tumors, whereas immunoreactivity for BMPR-IB was very mild. The myoepithelial cells proliferating within the basement membrane showed more intense immunoreactivity for BMP-6 and all BMPRs as compared with those proliferating in the interstitial areas. Western blotting analysis revealed immunopositive bands at 40–45 kDa for BMP-6 in the samples from simple and complex adenomas and benign mixed tumors. The BMPR-IB-specific bands at 45 kDa were most detected in benign mixed tumors. Because among BMPRs, BMPR-IB is thought to be the major receptor for BMP-6 for primary chondrogenesis, these findings suggest that the expression of BMP and its receptors on the myoepithelial cells might play a role in the ectopic cartilage formation in canine mammary gland tumors, especially in benign mixed tumors.

Ductal adenocarcinoma of the pancreas with psammomatous calcification: report of a case with immunohistochemical study for bone morphogenetic protein

We report a case of invasive ductal adenocarcinoma of the pancreas with psammomatous calcification. A 57-year-old man was admitted to our hospital complaining of abdominal pain and vomiting. Carcinoma of the head of the pancreas was diagnosed based on precise clinical examinations. A subtotal stomach-preserving pancreaticoduodenectomy was subsequently performed. Histological examination of the surgical specimen revealed a well-differentiated adenocarcinoma composed of irregular tubular structures involving the head of the pancreas. Conspicuously, numerous tiny psammomatous-type calcifications were observed, mainly within the neoplastic lumen, but also in association with carcinoma cells that had infiltrated the lymphatics and lymph nodes. In addition, expression of bone morphogenetic protein, cartilage and bone-inducing factor cloned from demineralized bone matrix and the transforming growth factor-β subfamily was immunohistochemically examined for carcinoma cells. Reactivity for multiple kinds of bone morphogenetic protein (types 5, 6 and 7) was identified in the cytoplasm of carcinoma cells. Psammoma body formation is an unusual event in invasive ductal adenocarcinoma of the pancreas, with only one similar case previously reported in the English literature. We also discuss the formation of psammomatous calcifications by pancreatic cancer cells.

A spindle cell carcinoma presenting with osseous metaplasia in the gingiva: a case report with immunohistochemical analysis

BACKGROUND

Spindle cell carcinoma (SpCC) is a rare, high malignant variant of squamous cell carcinoma (SCC), which shows biphasic proliferation of conventional SCC component and malignant spindle shape cells with sarcomatous appearance.

METHODS

A case of Spindle cell carcinoma with bone-like calcified materials, occurring at the mandibular molar region of 71-years-old Japanese male patient was presented with gross finding, histological findings and MRI image. To identify the characteristics of the bone-like materials, immunohistochemistry were performed.

RESULTS

Histologically, the cancer cells were composed of spindle cells and epithelial cells which form nests with prominent keratinization. Histological findings showed typical histology of the SpCC, however, as an uncommon finding, spatters of calcified, bone-like materials were observed in between the cancer cells. Immunohistochemistry revealed that cancer cells were positive for cytokeratins and vimentin to a varying degree and negative for Desmin, S-100, Osteopontin, BMP-2 or BMP-4. These findings implied that the calcified materials were formed by metaplasia of the stromal cells.

DISCUSSION

Bone-like materials formation by osseous and/or cartilaginous metaplasia of the stroma in the carcinoma has been reported. However, the detailed mechanism of these metaplasia and affection on the clinical feature, prognosis and therapies are not well established. In summary, we presented an unique case of SpCC, which has not been described in the literature.

Carcinosarcoma of the esophagus characterized by myoepithelial and ductal differentiations

We report a case of carcinosarcoma of the esophagus characterized by ductal and myoepithelial differentiation. A 61-year-old man was operated on for a polypoid tumor of the distal esophagus. Histologically, this tumor was composed of ductal structures and sarcomatous spindle cells surrounding the ducts at the central area of the tumor. The tumor was also composed of squamous cell and basaloid carcinoma in the periphery. Immunohistochemically, a few spindle cells surrounding the ductal structures showed immunopositivity for alpha-smooth muscle actin and S-100 protein. Electron microscopy revealed that the spindle cells had tonofilament and pinocytic vesicles in the cytoplasm, and basal lamina adjacent to the cytoplasmic membrane. Both of the results strongly supported the suggestion that the spindle cells may be myoepithelial cells. Basaloid carcinoma showed a gradual transition to chondrosarcomatous cells producing the matrix, which had both immunopositivities for S-100 protein and cytokeratin. Therefore, chondrosarcomatous cells may be derived from carcinoma cells. The histogenesis of this tumor may be associated with a totipotent stem cell of esophageal mucosa, which has the potential to differentiate into squamous cells, ductal cells or myoepithelial cells.

Expression of bone morphogenetic protein-6 (BMP-6) in myoepithelial cells in canine mammary gland tumors

Seventy-three mammary tumors and three mammary tissue specimens were examined to elucidate the expression of bone morphogenetic protein (BMP)-6 in the myoepithelial cells of canine mammary gland tumors. Morphologically, the myoepithelial cells were classified into four types: resting and proliferating cells inside the basement membrane, and spindle- and star-shaped cells proliferating in the outer area of the basement membrane. The characteristics of these myoepithelial cells were confirmed by immunohistochemistry using antibodies raised against keratin, cytokeratin 19, alpha-smooth muscle actin, and vimentin. In simple adenoma, a small number of resting myoepithelial cells was immunopositive for BMP-6. In complex adenomas and benign mixed tumors, all types of myoepithelial cells, depending in some cases on their specific location within the tumor, were immunopositive for BMP-6, but almost all of the tubular epithelial cells were immunonegative. Foci consisting of a proliferation of BMP-6-positive star- and spindle-shaped cells had mucinous stroma with marked hyaline and chondroid changes. In contrast, the foci with BMP-6-negative spindle- and star-shaped cells tended to have mucinous stroma without chondroid change. Several types of mesenchymal cells including chondrocytes, osteoblasts, and fibroblastlike cells in the mixed tumors, showed an intense immunopositive reaction for the BMP-6 antibody, and were located close to the ectopic cartilage and bone matrix. No significant immunoreactivity for BMP-6 was observed in most of the malignant mammary tumors; only one malignant mixed tumor was examined. All of these findings indicate that BMP-6 expression in myoepithelial cells may increase in complex adenomas and benign mixed tumors in canine mammary glands, and that BMP-6 expression is most intense in the vicinity of chondroid matrix in these tumors.