A statistically significant dose response was observed for all nervous system tumors combined and for schwannoma considered separately, indicating that exposure to even moderate doses (i.e., <1 Sv) of radiation is associated with an elevated incidence of nervous system tumors.

A case of duodenal gangliocytic paraganglioma (DGP) in a 17-year-old boy is presented. In this case a lymph node in the peripancreatic region was involved by a metastatic tumor. A review of the literature on DGP indicates that this case represents the youngest patient and is the second case of DGP with metastasis. Immunohistochemical staining for neuron-specific enolase (NSE), neurofilament (NF), pancreatic polypeptide, and somatostatin showed positive results for epithelioid and ganglion-like cells, whereas spindle cells showed immunoreactivities for S-100 protein, NSE, and NF. The histogenesis of DGP is discussed.Cancer 63:2540-2545, 1989.UODENAL gangliocytic paraganglioma (DGP) is an D extremely rare tumor and its name is derived from the peculiar histologic pattern with a mixed feature of carcinoid tumor, paraganglioma, and ganglioneuroma. In 1957, Dahl et al.' described the first case which was diagnosed as ganglioneuroma and to date about 60 cases of DGP have been reported in the literature. Although almost all of the reported cases were considered to be benign, it has not been clear why a malignant counterpart of this tumor is very rare.* Many theories have been postulated concerning the histogenesis of DGP, but they have so far failed to fully explain this. More recently, some immunohistochemical have been performed using antibodies against a range of general and specific markers for neuroendocrine cells, but the histogenesis of this tumor still remains unclear.We present a case of DGP which occurred in a 17-yearold boy. To our knowledge, this is the youngest reported case and the second case with metastasis to a regional lymph node. We also review briefly the literature on DGP. Case ReportA 17-year-old boy was hospitalized with a chief complaint of massive hematoemesis. His past history was not contributory. On the admission his consciousness was clear, although his systolic blood pressure was 60 mmHg, compatible with hypovolemic shock status. He received blood transfusion (1200 ml). Because of the second episode of hematoemesis, he underwent an exploratory laparotomy. A polypoid tumor was found involving Vater's papilla, and the surface was overlaid with duodenal mucosa, which was ulcerated and bleeding. The tumor was resected and a plastic surgery of choledochus and pancreatic duct was performed.Two months later, he underwent a pancreaticoduodenectomy (Child's procedure) with lymph node dissection. His postoperative course was uneventful and he was in good health without recurrence or metastasis 32 months after the surgery. Pathologic Examination Morphologic MethodsSections from routine, formalin-fixed and paraffinembedded tissues were examined light microscopically. Special staining procedures including periodic acid-Schiff (PAS), alcian blue, mucicarmine, Grimelius and FontanaMasson were performed.For immunohistochemistry, the paraffin sections were deparaffinized and processed for immunohistochemical technique using the avidin-biotin-peroxidase complex. Rabbit antibodies against the following antig...

Skin cancers, though rare in Japan, have reportedly been on the rise, but little else is known about epidemiologic features of different histologic types of skin cancer. The Life Span Study cohort, which consists of 93,700 atomic-bomb survivors, many of whom were exposed to negligibly low radiation doses, and 26,600 people not exposed to radiation, enables a population-based study of spontaneous as well as radiation-related cancer risk. Skin tumor incident cases diagnosed between 1958 and 1987 were ascertained by linkage to the Hiroshima and Nagasaki tumor registries augmented by searches of other data sources. Study pathologists reviewed tumor specimens and pathology reports and classified tumors using the World Health Organization classification scheme. They identified 274 primary incident skin cancers, of which 106 were basal cell carcinoma (BCC), 81 were squamous cell carcinoma (SCC), and 14 were malignant melanomas. Background incidence rates and radiation effects were assessed by Poisson regression models allowing for the effects of demographic and other covariates. BCC and SCC background incidence rates were both about 3 per 100,000 per year. BCCs were mainly on the head/neck (81%), whereas SCCs occurred most frequently on the arms/legs (45%) and head/neck (29%), consistent with the presumed role played by solar UV exposure in skin cancer. The BCC rates increased significantly between 1958 and 1987, whereas the SCC rates remained unchanged. The excess absolute risk of BCC per unit skin surface area related to atomic-bomb radiation exposure did not differ between UV-exposed and shielded parts of the body, suggesting the additivity of the radiation-related and background BCC risks. ' 2005 Wiley-Liss, Inc.Key words: basal cell carcinoma of the skin; squamous cell carcinoma of the skin; ionizing radiation; sun exposure Skin cancers are relatively rare in Japan. Age-adjusted incidence rates (per 10 5 per year) of melanoma are 0.2-0.5 in Japan compared to that of 10-20 in US whites and 30-40 in Australia. 1The incidence rates of about 1.0-5.5 for NMSC in Japan are much lower than US white rates of about 250.1,2 UV radiation is the major cause of skin cancer, involving all 3 major types: BCC, SCC and melanoma in fair-skinned Caucasian populations. 3,4 Except for the reportedly rising incidence of melanoma and BCC of the skin, 5,6 there have been little epidemiologic data on characteristics of skin cancer in Japan, especially by histologic types.IR has long been known to cause skin cancer, especially BCC, 3,4,7 and we previously reported the IR effect on BCC in the LSS cohort of atomic bomb survivors and controls.8 A large number of subjects (more than 57,000 or 51%) in this cohort were not or were only negligibly exposed (i.e., at <5 mSv) to radiation from the atomic bombs. This enabled us to analyze the background cancer rates by histologic type, taking advantage of the long-term cancer incidence follow-up.In our study, we describe the epidemiologic characteristics of background rates for the different histolog...

The basal layer of the epidermis appears to be quite sensitive to radiation carcinogenesis, particularly at a young age. The suprabasal layer seems to be more resistant, as shown by the lack of an association for squamous cell carcinomas.

Butylated hydroxytoluene (BHT), a preservative widely found in food as a food additive, was orally administered at concentrations of 1% and 2% of the diet to B6C3F1 mice for 104 consecutive weeks. Treated animals underwent a 16‐week recovery period prior to pathological examination. In male mice administered BHT, the incidence of mice with either a hepatocellular adenoma or a focus of cellular alteration in the liver was increased in a clear dose‐response relationship. The incidences of male mice with other tumors and the incidences of female mice with any tumor were not significantly increased as a consequence of BHT administration. The results of this study indicate BHT to be tumorigenic to the liver of the B6C3F1 male mouse.