The proto-oncogene c-fos is a major nuclear target for signal transduction pathways involved in the regulation of cell growth, differentiation, and transformation. Using the multistep skin carcinogenesis model, we have directly tested the ability of c-fos-deficient mice to develop cancer. Upon treatment with a tumor promoter, c-fos knockout mice carrying a v-H-ras transgene were able to develop...

Meningioma is considered as a benign central nervous system tumor that accounts for approximately 18% of all brain tumors. About 5% of meningioma tumors are malignant and have more aggressive clinical signs and worse prognosis compared to benign tumors. Extracranial metastasis of meningioma is rare but in the case of occurrence, it is more prevalent in lung, liver and lymph nodes. Osseous metas...

Background: Patients with oculocutaneous albinism (OCA) are prone to develop skin cancers. Aim and Objectives: To analyze reports of skin cancers in albinos published in the English and the Japanese literature in order to prepare guidelines for the successful management of skin cancer in albinos. Methods and Materials: We searched on PubMed, Web of Knowledge for English literature, and Ichushi-...

BACKGROUND Primary malignant tumors of the hand, although unusual, may present varied and often complex clinical problems. The main treatment modality of skin cancer of the hand has changed. METHODS We retrospectively reviewed the medical records of 43 patients who underwent surgery for malignant skin tumors of the hand during an 18-year period, from September 1994 to February 2012. The chara...

Ovarian malignant melanomas are extremely rare tumors. Most of them are secondary tumors and disseminated metastases are recognized at the time of diagnosis. Primary tumors are even more rare and usually associated with a teratoma. A 67-year-old female had a pelvic mass that was recognized on ultrasonography (USG) and physical examination. Intraoperative pathological consultation was reported a...

The scalp is the most frequent site of occurrence of malignant tumors. As an area that is generally neglected by the patient and not closely monitored during physical examinations, scalp tumors can go unnoticed until they become malignant. The present study reports 3 cases of rare giant malignant tumors of the scalp, namely a peripheral nerve sheath tumor, a fibrous tumor and a malignant prolif...

The concept that leprosy is rarely associated with cancer prevail ed until 1937 to such .an extent that it was believed that persons with leprosy were immune to malignan t tumors. This point of view was due principally to the conclusions of Soegaard (H), who, in 1910, analyzed the deaths caused by cancer in leprosaria. Impressed by the fact that in the United States Levin (~a) had not found a s...

The pRb pathway is inactivated in most, if not all, human and mouse tumors, including skin tumors. However, a relatively low frequency of Rb gene alterations is found. The embryonic lethality of pRb-deficient animals restricts the analysis of these mice to midgestation and precludes the analysis of the roles of pRb in mouse cancer models. To solve this problem, we used the Cre/LoxP technology t...

Background & Aims: Early detection and reliable differentiation of benign and malignant liver tumors could lead to improved cure rate and costs. Ultrasound image (US) is a convenient medical imaging method for interpreting liver tumors. Visual inspection of ultrasound images sometimes is combined with error and needs biopsy to confirm whether a tumor would be benign or malignant. The aim of thi...

Various benign and malignant non-melanocytic tumors, including skin appendage tumors, sometimes accompany non-neoplastic melanocytes, and this phenomenon has been described as “melanocytic colonization” [1-7]. Porocarcinoma is a rare skin appendage carcinoma related to the sweat gland duct, originally described by Pinkus and Mehregan in 1963 [8]. Its incidence is reported to be 0.004% of skin b...