"Secretory" Carcinoma of the Skin Mimicking Secretory Carcinoma of the Breast: Case Report and Literature Review.

Secretory carcinoma is a unique kind of adenocarcinoma. It has distinct histological features and a special genetic change, that is, t (12; 15) (p13; q25) translocation which leads to the expression of the ETV6-NTRK3 fusion gene. Secretory carcinoma has been found to occur both in the breast and salivary gland. Here the authors present a case of 22-year-old woman with a unique cutaneous neoplasm located at the axilla. The tumor was characterized histologically with the formation of round to ovoid microcysts and papillary structure, which was similar to the secretory carcinoma of the breast and salivary gland. Furthermore, the gene sequence analysis of reverse-transcription polymerase chain reaction products demonstrated the expression of the ETV6-NTRK3 fusion gene. To the authors' knowledge, this is the first case of secretory carcinoma from the skin which has the same genetic change as those from the breast and salivary gland. Local excision was performed on this patient. She had been followed up for nearly 1 year. No recurrence or metastasis was found yet.

[Tumors with poroid features: a clinicopathologic analysis of 45 cases].

OBJECTIVE: To investigate the clinicopathological features and the differential diagnosis of poroma and porocarcinoma. METHODS: Histopathological characteristics and clinical data of 35 cases of poroma and 10 cases of porocarcinoma were analyzed retrospectively. RESULTS: The average age of 35 patients of poroma was 48 years. The average age of 10 patients of porocarcinoma was 65 years. Both poroma and porocarcinoma occured most frequently on the scalp and face,as well as the extremities. Histologically, cases of poroma were divided into three subtypes, including classic poroma (23 cases), hidroacanthoma simplex (3 cases) and dermal duct tumor (9 cases). Residual foci of benign poroma were found in all cases of porocarcinoma, most of which were classic poroma. The malignant components showed severe dysplasia and/or stromal infiltration. CONCLUSION: The diagnosis of poroma and porocarcinoma is mainly based on the microscopic characteristics. An invasive architectural pattern and/or significant cytologic pleomorphism are the most important clues for the diagnosis of porocarcinoma. Neither focal mitotic activity nor the presence of necrosis was the diagnostic feature of porocarcinoma. Malignant transformation can occur in some cases of long existing poroma with recent, rapid tumor enlargement.

[Fluorescence in-situ hybridization as a diagnostic tool for cutaneous melanoma].

OBJECTIVE: To explore the utility of fluorescence in situ hybridization as a diagnostic tool for cutaneous melanoma. METHODS: Twenty cutaneous melanomas and 20 cutaneous nevi from pathology files were selected and analyzed by Vysis melanoma FISH probe kit targeting 3 loci on chromosome 6 (MYB, CEP6 and RREB1) and 1 locus on 11q (CCND1) and data were interpreted based on the Abbott criteria provided by the kit. RESULTS: Informative FISH results were obtained in 16 melanomas and 18 nevi. Chromosomal aberrations were detected in 12 of the 16 melanomas and only 1 of 18 nevi. CONCLUSION: FISH is a useful diagnostic tool and able to distinguish cutaneous nevus from melanoma with good sensitivity and specificity.

[Pathology of enterovirus 71 infection: an autopsy study of 5 cases].

OBJECTIVE: To study the clinicopathologic features of fatal enterovirus 71 (EV71) infection. METHODS: Autopsy was performed in 5 neonates died of EV71 infection. Tissue samples from major organs were collected, formalin-fixed and examined under light microscopy. Immunohistochemical study was carried out in selected examples. RESULTS: Four of the 5 cases showed predominant changes in central nervous system, with encephalitis and encephalomyelitis identified mainly in brainstem and upper cervical spinal cord. Histologic findings included neuronal degeneration and necrosis, neuronophagia, perivascular cuffing and diffuse or nodular hyperplasia of macrophages/microglia. Cerebral edema, brain herniation and aseptic meningitis were also noted. The lungs showed mainly pulmonary congestion, neurogenic pulmonary edema and focal hemorrhage. There were minimal changes in the intestinal epithelium. The intestinal lymphoid tissue however was hyperplastic and associated with apoptosis of follicular center cells. The remaining case had cerebral edema and mild meningitis. The lung alveolar septa were thickened with lymphocytic infiltrates. Some alveolar cells were hyperplastic and associated with diffuse hyaline membrane formation. No specific abnormalities were identified in gastrointestinal tract. In all the 5 cases studied, there was enlargement of lung hilar and mesenteric lymph nodes, coupled with apoptosis of follicular center cells. In general, no significant pathologic changes were demonstrated in heart, liver and kidneys. CONCLUSIONS: In fatal EV71 infection, the major pathologic changes lie in the central nervous system. The pulmonary lesions are mainly secondary in nature. The usual cause of death is cerebral edema complicated by brain herniation and pulmonary edema. It is also noteworthy that some cases show only lung damages, without classic neurologic changes.

Carcinoid tumour in a lumbar teratoma associated with tethered cord syndrome in an adult.

An unusual case of a carcinoid tumour in a lumbar extradural teratoma presenting as tethered cord syndrome and spina bifida without carcinoid syndrome in a 51-year-old woman is reported. These entities existing simultaneously in the same region are extremely rare and this suggests they have a common origin.

[Roles of p57KIP2 immunohistochemistry and flow cytometry in diagnosis of molar pregnancy].

OBJECTIVE: To study the value of combined use of paternally imprinted gene product p57(KIP2) immunohistochemistry and flow cytometry in the differential diagnosis of placental hydropic diseases. METHODS: A total of 32 cases of hydropic placenta with DNA polymorphism information were collected, and the genetic results were used as basis for the diagnosis of complete hydatidiform moles (CHM), partial hydatidiform moles (PHM) or hydropic abortions. All cases were examined by histology, p57(KIP2) immunohistochemical staining (EnVision method) and flow cytometry DNA ploidy analysis. The p57(KIP2) immunohistochemical staining and DNA ploidy results were compared with the genetic results. RESULTS: In CHM, p57(KIP2) negative rates were 95.2% (20/21), whereas all the 11 cases of non-CHM (7 cases PHM and 4 cases hydropic abortions) were positive (11/11). In 11 p57(KIP2) -positive cases, 7 cases with triploidy and 4 cases with diploidy by flow cytometry were proven to be PHM and hydropic abortions by genetic analysis, respectively. Overall, 96.9% (31/32) cases of hydropic placentas were correctly diagnosed by combined use of p57(KIP2) immunohistochemistry and flow cytometry. CONCLUSIONS: p57(KIP2) immunohistochemical negativity is a reliable index for the diagnosis of CHM. Combined flow cytometry DNA ploidy and p57(KIP2) immunohistochemistry are useful in the pathological differentiation of CHM, PHM and hydropic abortions.

[Clinicopathologic analysis of pulmonary lymphangioleiomyomatosis].

OBJECTIVE: To investigate the clinicopathological features of pulmonary lymphangioleiomyomatosis (PLAM). METHODS: By means of HE and immunohistochemistry (SP method) studies, the clinical and pathological features of 5 PLAM cases were analyzed and the related literature reviewed. RESULTS: PLAM was a rare lung disease of unknown etiology and was restricted to females who were generally pre-menopausal. Pathological features showed abnormal smooth muscle cells (LAM cells) line the airways, lymphatics and blood vesssels leading to airflow obstruction and replacement of the lung parenchyma by cysts. LAM cells were positive for HMB45. Clinically the disease was categorized by dyspnoea, haemoptysis, recurrent pneumothoraces and chylous effusions. CONCLUSIONS: PLAM should be considered when recurrent pneumothorax, haemoptysis and dyspnoea occur in females. Pathologic examination of lung tissue biopsy is required for confirmation of PLAM diagnosis.

Severe acute respiratory syndrome associated coronavirus is detected in intestinal tissues of fatal cases.

OBJECTIVES: A significant percentage of confirmed severe acute respiratory syndrome (SARS) patients experienced gastrointestinal symptoms, and the viral sequence was detectable in the stool of most patients. At present, the knowledge of the pathology of the digestive system in SARS patients is limited. Because a resurgence of the SARS epidemic is constantly possible, there is an urgent need to understand the involvement of the digestive system in this new disease. METHODS: We performed seven SARS autopsies in which samples of alimentary tract and digestive glands were examined with routine pathology, electron microscopy (EM), in situ hybridization (ISH), immunohistochemistry, and real-time polymerase chain reaction (PCR). RESULTS: The main histopathological finding was atrophy of the mucosal lymphoid tissue. A few mucosal epithelial cells and lymphocytes in the intestine were positively stained for coronavirus with ISH. SARS-coronavirus (CoV)-like particles were found in the mucosal epithelial cells under EM and mild focal inflammation was detected in the alimentary tract. One patient who experienced severe diarrhea had pseudomembranous enteritis of the ileum. Fatty degeneration and central lobular necrosis were observed in the liver. No evidence of direct viral infection was found in the esophagus, the stomach, the salivary gland, the liver, or the pancreas. CONCLUSIONS: In addition to the lungs, the gastrointestinal tract is another target of SARS-CoV infection, as the intestinal epithelial cells and mucosal lymphoid tissue are infected. The findings provide possible explanations for the gastrointestinal symptoms and the presence of virus in the stool of SARS patients.

[Thymosin beta10 expression and actin filament organization in tumor cell lines with different metastatic potential].

OBJECTIVE: To investigate the expression of thymosin beta10 (Tbeta10) and related changes of actin filament organization in human tumor cell lines with different metastatic potential. METHODS: Four groups of nine human tumor cell lines with different metastatic potential were analyzed for the expression of Tbeta10 mRNA detected by northern-blot and its peptide by immunohistochemical staining. The filamentous actin (F-actin) was stained with TRITC-phalloidin to detect changes in actin organization. RESULTS: In comparison with the non and/or weakly metastatic counterparts, Tbeta10 was upregulated in highly metastatic human lung cancer, malignant melanoma and breast cancer cell lines. TRITC-phalloidin staining revealed less actin bundles and a fuzzy network of shorter filaments in the highly metastatic tumor cells, while in the non and/or weakly metastatic cancer cell lines, there were thick and orderly arranged actin filaments. CONCLUSIONS: Tbeta10 levels correlate positively with the metastatic phenotype in human tumors currently examined. The increased metastatic potential of tumor cells is accompanied by the loss of F-actin and poorly organized actin skeleton. There is a consistent correlation between the elevated Tbeta10 expression and the disrupted actin skeleton.