Sacrococcygeal yolk sac tumor developing after teratoma: a clinicopathological study of pediatric sacrococcygeal germ cell tumors and a proposal of the pathogenesis of sacrococcygeal yolk sac tumors.

PURPOSE: We evaluated the clinicopathological characteristics of pediatric sacrococcygeal germ cell tumors (SGCTs) and yolk sac tumors (YSTs) developing after sacrococcygeal teratoma (SCT) resection, and discussed the pathogenesis of sacrococcygeal YST. METHODS: We retrospectively analyzed pediatric SGCT patients attending 10 Japanese institutions. RESULTS: A total of 289 patients were eligible, of which 74.6% were girls. The mean age at surgery was 7.1months. There were 194 mature and 47 immature teratomas, and 48 YSTs. YST developed after SCT resection in 13 patients (5.4% of SCTs), and was detected between 5 and 30months after resection. At initial surgery, 9 of these 13 patients were neonates, 12 underwent gross complete resection with coccygectomy, and 9 had histologically mature teratoma without microscopic YST foci. Postoperative serum alpha-fetoprotein (AFP) levels were regularly examined in 11 patients. Intervals of AFP measurement≤4months helped to detect subclinical localized YSTs for resection. CONCLUSIONS: The characteristics of SGCT in Japanese children were similar with those reported in Europe or the United States. YST developed after SCT resection not only in patients with previously reported risk factors. We recommend that patients undergo serum AFP monitoring every 3months for≥3years after SCT resection.

A case of Epstein-Barr virus-associated pulmonary leiomyosarcoma arising five yr after a pediatric renal transplant.

EBV-associated SMTs in immuno-compromised patients have recently been reported. We report on a case of EBV-associated pulmonary leiomyosarcoma arising five yr after renal transplantation. The patient was an eight-yr-old girl, who received a living related kidney transplant from her mother. She had had bilateral giant Wilm's tumors as an infant and underwent bilateral nephrectomy at one and two yr of age. At the age of seven, she suffered from bronchitis several times, and a year later, two nodules were detected in her left lung by X-ray and computed tomography. We suspected a recurrence of Wilm's tumor and performed surgical resection. The pathological finding was SMT with moderate mitosis and no evidence of Wilm's tumor. The fact that the tumors were positive for EBER suggested an association with the EBV. Six months later, there was a recurrence in her left lung. Surgical resection was performed, and immunosuppressive agents were reduced. Two yr after the second operation, she is well with no recurrence. We report the first case of EBV-associated pulmonary leiomyosarcoma in a pediatric patient after renal transplantation owing to a malignant tumor.

Adrenal schwannoma: CT and MRI findings.

We report a case of adrenal schwannoma, an extremely rare retroperitoneal neoplasm. The patient was a 33-year-old man who presented with an abdominal mass that was discovered at abdominal sonography. Computed tomography showed an 8-cm well-circumscribed homogeneous mass that enhanced slightly after intravenous administration of contrast material. Magnetic resonance imaging showed low signal intensity on T1-weighted images and heterogeneously high signal intensity on T2-weighted images. Although these imaging findings are nonspecific, adrenal schwannomas should be included in the differential diagnosis of solid nonfunctioning adrenal tumors.

[A case of ascities decrease in malignant peritoneal mesothelioma by weekly intra-peritoneal administration of cisplatin and paclitaxel].

We report a case of malignant peritoneal mesothelioma (MPM) in a 63-year-old man. He had body weight loss and abdominal distension for one month, and was admitted to our hospital. Abdominal sonography showed a large mass occupying the right lower abdomen and an existence of a lot of ascites. Computed tomography and magnetic resonance image showed a lot of ascites and omentum cake. Cytology of the ascites was Class V but its histological classification was unknown. Then we performed biopsy of the tumor into the omentum with abdominal sonography. The histological diagnosis was MPM because the tumor cells showed positive for calretinin. He received a combination chemotherapy of weekly intra-peritoneal administration of cisplatin (70 mg/ day) and paclitaxel (100 mg/day). The ascites was decreased and per os (PO) was possible, but omentum cake was not changed. MPM was poor in prognosis and the control of ascites was difficult. We suggest that the chemotherapy of intra-peritoneal administration was a better procedure than others to control ascites with malignant tumors.

Autopsy case of CD4/CD8 cutaneous T-cell lymphoma presenting disseminated pagetoid reticulosis with aggressive granulomatous invasion to the lungs and pancreas.

Pagetoid reticulosis is a rare cutaneous T-cell lymphoma with striking epidermotropism similar to that present in Paget's disease. There are two forms of pagetoid reticulosis: localized and disseminated. Reported herein is an autopsy case of disseminated pagetoid reticulosis with CD4(-)/CD8(-) phenotype T cells and massive invasion of the lungs and pancreas. The abnormal cells in the epidermis expressed a protein derived from a rearranged T-cell receptor beta gene, and this feature was used to confirm the monoclonality of these cells by polymerase chain reaction. At present, the World Health Organization (WHO) classification system considers pagetoid reticulosis to be an indolent form of primary cutaneous T-cell lymphoma and a variant of mycosis fungoides/Sezary syndrome with prominent epidermotropism. Some differences have been observed between pagetoid reticulosis and mycosis fungoides in terms of clinical course, tumor cell phenotype, and genetic findings; and these differences are highlighted in the present case. The relation between disseminated pagetoid reticulosis, CD4(-)/CD8(-) cutaneous T-cell lymphoma, and gammadelta T-cell lymphoma, including whether pagetoid reticulosis is a variant of mycosis fungoides, remains unclear.