Multiple malignant epithelioid mesotheliomas of the liver and greater omentum: a case report and review of the literature.

BACKGROUND: Malignant mesothelioma commonly arises from the pleura, but can also arise from the peritoneum, pericardium, and tunica vaginalis testis. However, malignant mesothelioma of the liver is extremely rare and coexistence with malignant mesothelioma of the greater omentum has not been described in the literature. In this case report, we present a case of multiple malignant mesothelioma of the liver and greater omentum. CASE PRESENTATION: A 36-year-old woman was admitted to our hospital for the evaluation of an elastic hard mass in the right upper abdomen. Abdominal contrast computed tomography showed a cystic mass measuring 13 × 14 × 11 cm in the right liver lobe with enhanced mural nodule. Abnormal accumulation was identified in the liver and lower abdominal area on 18F-fluorodeoxyglucose positron emission tomography. The patient underwent hepatectomy of the posterior segment and partial resection of the omentum. The final pathological diagnosis was low-grade multiple malignant epithelioid mesothelioma based on characteristic immunohistochemical findings. As of 6 months postoperatively, the patient has shown no disease recurrence. CONCLUSIONS: We present the first case of a 36-year-old woman with multiple malignant mesothelioma of the liver and greater omentum.

Production of a High-affinity Monoclonal Antibody Reactive with Folate Receptors Alpha and Beta.

Folate receptors α (FRα) and ß (FRß) are two isoforms of the cell surface glycoprotein that binds folate. The expression of FRα is rare in normal cells and elevated in cancer cells. Thus, FRα-based tumor-targeted therapy has been a focus area of laboratory research and clinical trials. Recently, it was shown that a significant fraction of tumor-associated macrophages expresses FRß and that these cells can enhance tumor growth. Although FRα and FRß share 70% identity in their deduced amino acid sequence, a monoclonal antibody (MAb) reactive with both receptors has not been developed. A MAb that can target both FRα-expressing cancer cells and FRß-expressing tumor-associated macrophages may provide a more potent therapeutic tool for cancer than individual anti-FRα or anti-FRß MAbs. In this study, we developed a MAb that recognizes both FRα and FRß (anti-FRαß). The anti-FRαß specifically stained trophoblasts and macrophages from human placenta, synovial macrophages from rheumatoid arthritis patient, liver macrophages from cynomolgus monkey and common marmoset, and cancer cells and tumor-associated macrophages from ovary and lung carcinomas. Surface plasmon resonance showed that the anti-FRαß bound to soluble forms of the FRα and FRß proteins with high affinity (KD=6.26×10(-9) M and 4.33×10(-9) M, respectively). In vitro functional analysis of the anti-FRαß showed that this MAb mediates complement-dependent cytotoxicity, antibody-dependent cellular cytotoxicity, and antibody-dependent cellular phagocytosis of FRα-expressing and FRß-expressing cell lines. The anti-FRαß MAb is a promising therapeutic candidate for cancers in which macrophages promote tumor progression.

Synchronous bilateral breast cancer in a male patient following hormone therapy for prostate cancer.

We report an unusual case of bilateral, synchronous breast cancer in a male patient who had a history of estrogen therapy for prostate cancer. A 64-year-old Japanese man was diagnosed with T1N0M0 prostate cancer and received a total prostatectomy. Twenty months after the resection, the patient developed multiple bone metastases, and received radiation therapy, systemic chemotherapy, and hormone therapy for 15 months. After completing this treatment, he was diagnosed with T1N0M0 primary breast cancer in his left breast and underwent a modified mastectomy. Five months after the mastectomy he received systemic chemotherapy followed by estrogen therapy because of the progression of prostate cancer. Three months after this treatment, he was diagnosed with T1N0M0 primary breast cancer in his right breast. To the best of our knowledge, this is a rare case of synchronous bilateral male breast cancer following hormone therapy for prostate cancer.

Adenoma of the nipple: report of a case.

We report a case of an adenoma of the nipple in a 33-year-old Japanese woman who presented with a 2-year history of itching, eczema, and discharge from the left nipple. Examination revealed a firm, well defined and erosive tumor measuring 10 x 11 mm that was sore, crusted, and indurated. There was a slight serosanguineous discharge from the tumor. Cytological material from the tumor obtained from the discharge and by fine needle aspiration (FNA) and scraping showed a papillary cell cluster thought to be a benign papilloma. We performed a tumor resection with preservation of the nipple. The histological diagnosis was adenoma of the nipple. The patient was left with a cosmetically well-preserved nipple. No recurrent tumor has been observed for two years after surgery.

The antimetastatic role of thrombomodulin expression in islet cell-derived tumors and its diagnostic value.

Islet cell tumors, endocrine neoplasm arising from pancreatic islets of Langerhans, are histologically difficult to diagnose as benign or malignant. Molecular markers are associated with the clinical characteristics that most of insulinoma are usually benign tumors, whereas other islet cell tumors are malignant but have not been identified. In this context, we newly found that an endothelial anticoagulant thrombomodulin was expressed in the normal islet beta cells and insulinoma, but not of other islet components or noninsulinoma islet cell tumors. Clinically, all of the subjects (n=15) of the insulinoma group showed no metastasis together with thrombomodulin expression in the lesions, whereas the other islet cell tumor groups showed a high incidence of metastasis (82%) and a low expression rate of thrombomodulin (6%). To examine the functional role of thrombomodulin, especially regarding the clinical characteristics of islet cell tumors, we tested the effect of exogenous thrombomodulin overexpression on cell adhesiveness and proliferation using MIN6 insulinoma cell line. In cell-based experiments, thrombomodulin overexpression reduced cell proliferation and enhanced Ca2+-independent cell aggregation, possibly through direct interaction with neural cell adhesion molecule. Taken together, these results are suggesting that thrombomodulin may act as antimetastatic molecule of insulinomas. In addition, thrombomodulin is a clinically useful molecular marker not only for identifying beta-cell-origin islet cell tumors (i.e., insulinomas) but also for predicting disease prognosis of islet cell tumors.

Primitive neuroectodermal tumor of the transverse colonic mesentery defined by the presence of EWS-FLI1 chimeric mRNA in a Japanese woman.

We report a case of primitive neuroectodermal tumor (PNET) arising in the transverse colonic mesentery. A 24-year-old Japanese woman was admitted to Kagoshima City Hospital with complaints of abdominal pain and sensations of abdominal fullness of 5 months' duration. On palpation, a mass the size of an infant's head was noted in the right flank. Abdominal computed tomography (CT) and ultrasonography showed a huge mass that consisted of multiple cystic components. On arteriography, a slight tumor stain appeared, with stretched and displaced tributaries of the right colic and middle colic arteries. Barium swallow examination demonstrated that the ascending colon was shifted to the right and small intestine to the left. We performed an en-bloc resection of the tumor in the transverse colonic mesentery, including the ascending colon, proximal jejunum (20 cm in length), and greater omentum. The resected tumor was 12 x 10 x 7 cm in size, 590g in weight, elastic soft in consistency, and multicystic. Histologically, the specimens showed a sheet-like proliferation of spindle-to-polygonal cells, and focally, the tumor formed rosette structures. Immunohistochemically, the tumor cells were positive for neuron-specific enolase (NSE) and mic-2. EWS-FLI1 chimeric mRNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). Based on the above findings, we finally diagnosed the tumor as PNET of the colonic mesentery. There has been no recurrence for 20 months after operation. PNET arising in the mesentery is very rare, and we distinguished PNET from other tumors by immunohistochemical examination and by demonstration of the presence of EWS-FLI1 chimeric mRNA in the tumor.

Expression of mucin core proteins in extramammary Paget's disease.

Extramammary Paget's disease (EPD) is a relatively common skin cancer wherein tumor cells have mucin in their cytoplasm. However, little is known about mucin expression in EPD. We examined immunohistochemically the expression of mucin core proteins (MUC1, MUC2, MUC5AC and MUC6) in 36 cases of EPD and found different patterns of expression in intraepithelial (n = 36), microinvasive (n = 13) and invasive lesions (n = 6). In normal skin, MUC1 was expressed in the sebaceous, eccrine and apocrine glands. MUC2, MUC5AC and MUC6 were not expressed in any of these. In the 36 intraepithelial lesions, MUC1 and MUC5AC were expressed in 35 and 36 lesions, respectively. MUC1 expression was also observed in all 13 microinvasive lesions and in all six invasive lesions. In contrast to the intraepithelial lesions, a decrease or loss of MUC5AC expression was observed in five out of 13 microinvasive lesions and in all six invasive lesions. MUC2 and MUC6 were not expressed in any of the EPD lesions examined. The combination of immunohistochemical staining for MUC1 and MUC5AC was useful for identifying invasive Paget cells. The decrease or loss of MUC5AC expression may have an important role in the invasive growth of Paget cells.