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PubMed2006

[Cardiac transplantation and neoplasms: experiences at Escola Paulista de Medicina of the Federal University of São Paulo].

OBJECTIVE: To study the occurrence and types of neoplasms developed by patients who underwent an orthotopic cardiac transplantation under the Program of Cardiac Transplantation of Escola Paulista de Medicina, Federal University of São Paulo. METHODS: This is an observational study of 106 patients who underwent orthotopic cardiac transplantation from November 1986 to September 2002 and survived at least thirty days following the procedure. The triple immunosuppressive regimen given included cyclosporin A, azathioprine and a corticosteroid agent. Only two patients received OKT3 in addition to the regimen established. Mean follow-up was 61.4 months (ranging from two months to 192 months). RESULTS: Twenty-three patients (21.3%) developed neoplasms--56.5% of these were skin neoplasm, 30.1%, solid tumors, and 13.4% of post-transplant lymphoproliferative disease (PTLD). Mean interval between transplantation and diagnosis of neoplasm was: 54.9 months for skin neoplasm; 24.8 months for solid tumors and 70.3 months for PTLD. CONCLUSION: Malignant neoplasms are relatively common in the population studied. Skin cancer was the most common type compared to the other types of neoplasms. Solid tumors were more frequently diagnosed than the lymphoproliferative diseases in the population examined.

Adolescent↗
PubMed2001

Tissue- and urokinase-type plasminogen activators and type 1 plasminogen activator inhibitor in melanomas and benign skin pigment neoplasms.

The content of urokinase- and tissue-type plasminogen activators and plasminogen activator inhibitor PAI-1 in the cytosol of primary and metastatic melanomas and benign skin pigment neoplasms was estimated by enzyme immunoassay. It was shown that local growth and invasion of melanomas are related to suppressed expression of tissue plasminogen activator. The content of urokinase plasminogen activator increases in patients with distant metastases and large thickness of the primary tumor.

Adult↗
PubMed2005

Genetics of skin appendage neoplasms and related syndromes.

In the past decade the molecular basis of many inherited syndromes has been unravelled. This article reviews the clinical and genetic aspects of inherited syndromes that are characterised by skin appendage neoplasms, including Cowden syndrome, Birt-Hogg-Dube syndrome, naevoid basal cell carcinoma syndrome, generalised basaloid follicular hamartoma syndrome, Bazex syndrome, Brooke-Spiegler syndrome, familial cylindromatosis, multiple familial trichoepitheliomas, and Muir-Torre syndrome.

Carcinoma, Skin Appendage↗
PubMed1986

NTP Toxicology and Carcinogenesis Studies of o-Phenylphenol (CAS No. 90-43-7) Alone and with 7,12-Dimethylbenz(a)anthracene (CAS No. 57-97-6) in Swiss CD-1 Mice (Dermal Studies).

o-Phenylphenol is used primarily as a germicide and fungicide for citrus fruits and vegetables and was selected for carcinogenesis studies because of the potential for human exposure. Four-week studies were conducted in which groups of 10 male and 10 female Swiss Webster mice were given dermal applications to the dorsal interscapular region of 0, 6, 11, 21, 36, or 56 mg of o-phenylphenol in 0.1 ml of acetone. Doses were administered 3 days per week for 4 weeks, and animals were monitored for clinical changes. Reductions in body weights of acetone vehicle control were observed, but no compound-related changes in weight or survival occurred in male or female mice administered o-phenylphenol. o-Phenylphenol caused dose-related ulcerative lesions at the site of application. The severity of these lesions was judged not to be life threatening. Carcinogenesis studies were conducted to determine whether o-phenylphenol was a complete carcinogen for skin or a promoter in a two-stage initiation/promotion skin paint model. Groups of 50 Swiss CD-1 mice of each sex were used for up to 102 weeks. Five dose groups were used: an acetone vehicle control group; a positive control group initiated with 7,12-dimethylbenz(a)- anthracene (DMBA) and promoted with 12-O-tetradecanoylphorbol-13-acetate (TPA); an initiator control group that received DMBA plus acetone; a group that received repeated applications of o-phenylphenol. The following doses were applied dermally to a clipped area on the dorsal interscapular region 3 days per week: o-phenylphenol - 55.5 mg/0.1 ml acetone; or TPA - 0.005 mg/0.1 ml acetone. DMBA was administered as a single dose at a concentration of 0.05 mg/0.1 ml acetone to the dorsal interscapular region. In the 2-year studies, mean body weights of the o-phenylphenol, DMBA/o-phenylphenol, and DMBA/TPA groups were not markedly different from those of mice that received DMBA/acetone. Similarly, there were no significant group differences in survival except for a decrease in survival in the positive control group (DMBA/TPA). Skin neoplasms classified as squamous cell papillomas, squamous cell carcinomas, basal cell tumors, basal cell carcinomas, keratoacanthomas, or sebaceous adenomas occurred in mice dosed with DMBA/acetone, DMBA/o-phenylphenol, or DMBA/TPA alone. However, the incidence of skin neoplasms in mice dosed with DMBA/acetone (15/100) was similar to that in mice dosed with DMBA/o-phenylphenol (17/100). The incidence of skin neoplasms in male and female mice dosed with DMBA/TPA (52/100) was substantially greater than those in mice dosed with either DMBA/acetone or DMBA/o-phenylphenol. Similarly, the mean time of appearance of skin papillomas occurred much earlier in the DMBA/TPA groups than in the DMBA/acetone or DMBA/o-phenylphenol groups. All groups had nonneoplastic lesions consisting of inflammation, ulceration, hyperkeratosis, and acanthosis at the site of application. These lesions were present in the acetone vehicle control group and, to a larger extent, in the o-phenylphenol, DMBA/o-phenylphenol, and DMBA/TPA groups. No skin neoplasms were observed in male or female mice receiving o-phenylphenol or in the acetone vehicle control groups. Moreover, a complete histopathologic review revealed no other neoplasms at any other site at significantly increased incidences in the groups receiving o-phenylphenol compared with the acetone vehicle controls. There were also no tumor-enhancing (or tumor-inhibiting) effects of o-phenylphenol and DMBA given in combination. o-Phenylphenol was weakly mutagenic in strains TA1535 of Salmonella typhimurium only in the absence of rat liver S9; it was not mutagenic in strains TA1537, TA98, or TA100. It was mutagenic in the mouse lymphoma L5178/TK+/- assay in the presence or absence of Aroclor 1254-induced male F344 rat liver S9. o-Phenylphenol did not induce sex-linked recessive lethal mutations in Drosophila melanogaster. o-Phenylphenol induced sister-chromatid exchanges in Chinese hamster ovary (CHO) cells only in the absence of rat liver S9. It did not induce chromosomal aberraterrations in CHO cells in the presence or absence of Aroclor 1254-induced male Sprague-Dawley rat liver S9. An audit of the experimental data was conducted for these 2-year studies of o-phenylphenol. No data discrepancies were found that influenced the final interpretations. Under the conditions of these 2-year dermal application studies, there was no evidence of carcinogenicity in male or female Swiss CD-1 mice administered o-phenylphenol alone or as a promoter following initiation with DMBA. o-Phenylphenol, however, caused nonneoplastic lesions, which included ulceration, inflammation, and hyperkeratosis, at the site of application.

Journal Article↗
PubMed2005

Composite and free cartilage grafting.

The nasal ala and helical rim of the ear are common sites for the development of skin neoplasms. Removal of skin cancers from these aesthetically delicate areas may leave defects that free skin grafts alone may not adequately repair. The contractural forces of scarring within and around the skin graft during healing may produce elevation or notching of the rim and may lead to functional compromise. The use of a composite graft or the inclusion of a free cartilage graft in conjunction with a skin graft or flap repair can provide structural support, which may help to prevent undesirable outcomes. This article focuses on the use of composite or free cartilage grafts harvested from the ear to repair nasal alar or helical rim defects within a single surgical session. Preoperative considerations, surgical technique, and postsurgical complications are discussed.

Cartilage↗
PubMed1999

Malignant rhabdoid tumor beside benign skin mesenchymal neoplasm with myofibromatous features.

Only a few reports of primary cutaneous rhabdoid tumors have been published. We describe the case of a 3-month-old female patient who developed a rhabdoid type cutaneous sarcomatoid neoplasm in her upper back, close to a benign myofibromatous proliferation of infancy. The lesion was studied both by light microscopy and immunohistochemically. Flow cytometry was performed showing a DNA diploid profile of the malignant tumor. The pathological findings suggest a mesenchymal origin (hemangiopericytic or myofibroblastic type) for both tumors. The patient was surgically treated, but she died nine months later.

Biomarkers, Tumor↗
PubMed1995

NTP Toxicology and Carcinogenesis Studies of Diethylphthalate (CAS No. 84-66-2) in F344/N Rats and B6C3F1 Mice (Dermal Studies) with Dermal Initiation/ Promotion Study of Diethylphthalate and Dimethylphthalate (CAS No. 131-11-3) in Male Swiss (CD-1(R)) Mice.

Diethylphthalate and dimethylphthalate are used as phthalate plasticizers, in an extensive array of products. The chronic dermal toxicity of diethylphthalate was evaluated in male and female F344/N rats and B6C3F1 mice in 2-year studies. In a series of special studies, the tumor initiation or promotion potential of diethylphthalate or dimethylphthalate was evaluated in male Swiss (CD-1(R)) mice by an initiation/promotion model of skin carcinogenesis. The genetic toxicity of diethylphthalate and dimethylphthalate in Salmonella typhimurium and cultured Chinese hamster ovary cells was also evaluated. 4-WEEK STUDY IN F344/N RATS: Groups of 10 male and 10 female rats were dermally administered diethylphthalate at volumes of 0, 37.5, 75, 150, or 300 &mgr;L (0, 46, 92, 184, or 369 &mgr;g) applied neat, 5 days per week for 4 weeks. All male and female rats survived to the end of the study. No evidence of dermatotoxicity was observed, with no adverse clinical signs observed and no effects on weight gain or feed consumption. Relative liver weights of 300 &mgr;L males and females and 150 &mgr;L females were greater than those of controls. Relative kidney weights of 150 and 300 &mgr;L males and 150 &mgr;L females were greater than those of controls. No other adverse effects were observed in this study. 4-WEEK STUDY IN B6C3F1 MICE: Groups of 10 male and 10 female mice were dermally administered diethylphthalate at volumes of 0, 12.5, 25, 50, or 100 &mgr;L (0, 15, 31, 62, or 123 &mgr;) applied neat, five days per week for 4 weeks. One control female died before the end of the study; all other mice survived. No evidence of dermatotoxicity or other adverse clinical signs were observed, and no clear adverse effects on weight gain or feed consumption were seen. Absolute and relative liver weights of 25 and 100 &mgr;L females were greater than those of the controls. Based on these 4-week study results, doses of 0, 35, and 100 &mgr;L diethylphthalate were recommended for the 2-year mouse studies. A chronic study in male and female B6C3F1 mice at 0, 35, and 100 &mgr;L (applied neat, once per day, 5 days per week) was started and subsequently stopped after 32 weeks when significant body weight reductions were noted in treated animals (males and females, 100 &mgr;L groups: 19% lower; males, 35 &mgr;L group: 12% lower; females, 35 &mgr;L group: 10% lower than controls). Based on these body weight reductions, doses of 0, 7.5, 15, and 30 &mgr;L in 100 &mgr;L acetone were recommended for the restart of the 2-year mouse study. 2-YEAR STUDY IN F344/N RATS: Based upon the results of the 4-week study, doses of 0, 100, or 300 &mgr;L diethylphthalate (0, 123, or 369 &mgr;) were chosen for the 2-year rat study. Groups of 60 male and 60 female rats received the doses applied neat 5 days per week for 103 weeks and up to 10 animals per group were evaluated after 15 months. Survival, Body Weights, and Clinical Findings: Survival of dosed rats during the first 15 months was similar to that of controls. However, 2-year survival was significantly reduced in all groups of male rats (survival probabilities, males: 0 &mgr;L, 8%; 100 &mgr;L, 12%; and 300 &mgr;L, 12%). The mean body weights of 300 &mgr;L males were slightly less than those of the controls throughout the study. No adverse clinical signs were observed, including no evidence of dermatotoxicity. Pathology Findings: No morphological evidence of dermal or systemic toxicity was observed in male or female rats. Skin neoplasms were not observed in female rats and were only rarely observed in male rats. A high incidence of anterior pituitary adenoma occurred in all groups of male and female rats. The incidence of anterior pituitary adenomas in the 0, 100, and 300 &mgr;L groups were: males, 39/44, 41/49, 41/49; females, 38/50, 33/49, 33/48. The incidence of this benign tumor in control males (84%) exceeded the historical control mean incidence [feed controls, (28.7%)] and range (12% to 60%). Anterior pituitary adenomas were considered a primary contributing factor in the increased mortality observed in all grtor in the increased mortality observed in all groups, regardless of treatment. A dose-related decreasing trend in the incidence of mammary gland fibroadenomas was observed in female rats (21/50, 12/48, 7/50). The incidence of mononuclear cell leukemia in male rats in this study was lower than the historical incidence and may be attributable to the shortened life span of male rats. Similarly, the incidence of interstitial cell tumors of the testes was markedly decreased in all groups of males (4/50, 3/50, 8/50), relative to historical control rates (90.1%; range 74%-98%). The incidence of fatty liver degeneration was notably lower in dosed rats than in controls (males: 26/50, 8/50, 4/51; females: 23/50, 11/50, 3/50). 2-YEAR STUDY IN B6C3F1 MICE: Groups of 60 male and 60 female mice received doses of 0, 7.5, 15, or 30 μL diethylphthalate (0, 9, 18, or 37 μ) in 100 μL acetone 5 days per week for 103 weeks with a 1 week recovery period, and up to 10 animals per group were evaluated after 15 months. Survival, Body Weights, and Clinical Findings: Two-year survival of dosed mice was similar to that of controls: 43/50, 41/48, 46/50, and 43/50 (males), and 41/50, 38/51, 37/49, and 36/49 (females). Mean body weights of dosed male and female mice were similar to those of the controls throughout the study. No adverse clinical signs were observed in mice, including no gross evidence of dermatotoxicity. Feed consumption by male and female mice was similar to or up to 13% greater than that by controls. Pathology Findings: No morphological evidence of dermal toxicity was observed in male or female mice. No skin neoplasms were observed in dosed male mice. In female mice receiving 30 μL, one squamous cell carcinoma and one basal cell carcinoma were seen at the site of application. An increased incidence of liver neoplasms was observed in dosed male and female mice. The incidence of hepatocellular adenoma or carcinoma (combined) in B6C3F1 mice in the 0, 7.5, 15, and 30 μL groups were: (males) 9/50, 14/50, 14/50, and 18/50; (females) 7/50, 16/51, 19/50, and 12/50. The incidence of adenoma or carcinoma (combined) was increased in 30 μL male mice and the incidences of adenoma and of adenoma or carcinoma (combined) were increased in 7.5 and 15 μL females. A positive dose-related trend in the incidence of adenoma or carcinoma (combined) was also observed in male mice. The incidence of basophilic hepatic foci was increased in 15 μL male mice (0/50, 1/50, 9/50, 3/50). The increased incidence of liver neoplasms in this study was considered equivocal because the incidence of hepatocellular neoplasms in control and dosed males was within the historical range and because there was no clear dose-response relationship in females. No other treatment-related findings were observed in this study. 1-YEAR INITIATION/PROMOTION STUDY IN MALE SWISS (CD-1®) MICE: Groups of 50 male mice were dosed dermally with diethylphthalate or dimethylphthalate to study their effect as initiators and promoters. Diethylphthalate and dimethylphthalate were tested as initiators with and without the known skin tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Diethyl phthalate and dimethylphthalate were tested as promoters with and without the known skin tumor initiator 7,12-dimethylbenzanthrancene (DMBA). Comparative control groups used during the study of diethylphthalate and dimethylphthalate included: vehicle control (acetone/acetone); initiation/promotion control (DMBA/TPA); initiator control (DMBA/acetone); and promoter control (acetone/TPA). Based on the incidence of skin neoplasms diagnosed histologically and the multiplicity of skin neoplasms, there was no suggestion that either diethylphthalate or dimethylphthalate was able to initiate skin carcinogenesis when chronically promoted by TPA. Further, there was no evidence that either diethylphthalate or dimethylphthalate was able to promote skin carcinogenesis in skin previously initiated with DMBA. High incidences of both squamous cell papillomas and squamous cell carcinomas occurred among the initiation/promotion control animals initiated with DMBA and promoted with TPA. All TPA-dosed groups had significantly greater incidences of dermal acanthosis, ulceration, exudation, and hyperkeratosis than controls. GENETIC TOXICOLOGY: Neither diethylphthalate (10-10,000 μ/plate) nor dimethylphthalate (33-6,666 μ/plate) induced gene mutations in Salmonella typhimurium strains TA98, TA100, TA1535, or TA1537, with or without rat and hamster liver S9. In cultured Chinese hamster ovary cells, both diethylphthalate and dimethylphthalate induced sister chromatid exchanges in the presence of S9. Neither induced sister chromatid exchanges in the absence of S9. Neither chemical induced chromosomal aberrations, with or without S9, in cultured Chinese hamster ovary cells. CONCLUSIONS: Under the conditions of these 2-year dermal studies, there was no evidence of carcinogenic activity of diethylphthalate in male or female F344/N rats receiving 100 or 300 μL. The sensitivity of the male rat study was reduced due to low survival in all groups. There was equivocal evidence of carcinogenic activity of diethylphthalate in male and female B6C3F1 mice based on increased incidences of hepatocellular neoplasms, primarily adenomas. In an initiation/promotion model of skin carcinogenesis, there was no evidence of initiating activity of diethylphthalate or dimethylphthalate in male Swiss (CD-1®) mice. Further, there was no evidence of promotion activity of diethylphthalate or dimethylphthalate in male Swiss (CD-1®) mice. The promoting activity of TPA following DMBA initiation was confirmed in these studies. Minor dermal acanthosis was observed following dermal application of diethylphthalate in male and female F344/N rats dosed for 2 years and in male Swiss (CD-1®) mice dosed for 1 year. Synonyms: Diethylphthalate (CAS No. 84-66-2): 1,2-benzenedicarboxylic acid, diethyl ester; DEP; diethyl 1,2-benzenedicarboxylate; diethyl o-phthalate; diethyl phthalate; ethyl phthalate; o-benzenedicarboxylic acid diethyl ester; phthalic acid, diethyl ester; RCRA U088 Dimethylphthalate (CAS No. 131-11-3): 1,2-benzenedicarboxylic acid, dimethyl ester; dimethyl 1,2-benzenedicarboxylate; dimethyl benzene-o-dicarboxylate; dimethyl benzeneorthodicarboxylate; dimethyl o-phthalate; dimethyl phthalate; DMP; FIFRA 028002; methyl phthalate; go-dimethyl phthalate; phthalic acid, dimethyl ester; phthalic acid methyl ester; RCRA U102

Journal Article↗
PubMed2006

Skin adnexal neoplasms--part 2: an approach to tumours of cutaneous sweat glands.

Tumours of cutaneous sweat glands are uncommon, with a wide histological spectrum, complex classification and many different terms often used to describe the same tumour. Furthermore, many eccrine/apocrine lesions coexist within hamartomas or within lesions with composite/mixed differentiation. In addition to the eccrine and apocrine glands, two other skin sweat glands have recently been described: the apoeccrine and the mammary-like glands of the anogenital area. In this review (the second of two articles on skin adnexal neoplasms), common as well as important benign and malignant lesions of cutaneous sweat glands are described, and a summary for differentiating primary adnexal neoplasms from metastatic carcinoma is outlined, striving to maintain a common and acceptable terminology in this complex subject. Composite/mixed adnexal tumours are also discussed briefly.

Adenoma, Pleomorphic↗
PubMed2002

Toxicology and carcinogenesis studies of o-nitrotoluene sulfone (CAS no. 88-72-2) in F344/N rats and B6C3F(1) mice (feed studies).

UNLABELLED: [structure: see text] o-Nitrotoluene is used to synthesize agricultural and rubber chemicals, azo and sulfur dyes, and dyes for cotton, wool, silk, leather, and paper. o-Nitrotoluene was nominated for study by NIOSH and the NTP based on its considerable human exposure as well as the absence of long-term studies of carcinogenicity in rodents. Male and female F344/N rats and B6C3F1 mice were exposed to o-nitrotoluene (greater than 99% pure) in feed for 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, cultured Chinese hamster ovary cells, rat and mouse bone marrow cells, and mouse peripheral blood erythrocytes. 2-YEAR STUDY IN RATS: In the core study, groups of 60 male and 60 female rats were fed diets containing 625, 1,250, or 2,000 ppm o-nitrotoluene (equivalent to average daily doses of approximately 25, 50, or 90 mg o-nitrotoluene/kg body weight to males and 30, 60, or 100 mg/kg to females) for 105 weeks. In a 3-month stop-exposure study, groups of 70 male rats were fed diets containing 2,000 or 5,000 ppm o-nitrotoluene (equivalent to average daily doses of approximately 125 or 315 mg/kg) for 13 weeks followed by undosed feed for the remainder of the study. A group of 70 male rats receiving undosed feed served as a control group for both male rat studies; 60 female rats receiving undosed feed were the control group for the female core study. Ten control males and 10 males from each stop-exposure group were sacrificed at 3 months. Survival, Body Weights, and Feed Consumption: All 2,000 ppm core study, all 5,000 ppm stop-exposure, and all but three core study 1,250 ppm male rats died before the end of the studies. Survival of 625 ppm core study and 2,000 ppm stop-exposure males and of 2,000 ppm females was significantly less than that of the controls. Mean body weights of all exposed groups of males except the 625 ppm group were generally less than those of the controls throughout the study. Mean body weights of 2,000 ppm females were less than those of the controls during year 2 of the study. Feed consumption by exposed groups of rats was similar to that by the controls. Biomarkers of Exposure: Three urinary metabolites were followed during the study as biomarkers of exposure. The ratios of o-nitrobenzoic acid to creatinine and of o-nitrobenzylmercapturic acid to creatinine determined at 2 weeks and at 3, 12, and 18 months were linearly related to exposure concentration in males and females. The ratio of o-aminobenzoic acid to creatinine was not related to exposure concentration. Pathology Findings: The incidences of malignant mesothelioma in male rats occurred with positive trends in both the core and stop-exposure studies and were significantly greater in exposed groups than in the controls. Incidences of subcutaneous skin neoplasms (fibroma, fibrosarcoma, and lipoma) were increased in exposed groups of males, while the incidences of fibroma or fibrosarcoma (combined) were increased in exposed females. In all exposed groups of males and females except 2,000 ppm core study males, the incidences of mammary gland fibroadenoma were significantly increased. The incidences of mammary gland hyperplasia were significantly increased in 625 and 1,250 ppm females. Increased incidences of mesothelioma, skin neoplasms, and mammary gland fibroadenoma in the stop-exposure males indicated that 3 months of dosing were sufficient to produce a carcinogenic effect. Liver weights of 5,000 ppm stop-exposure males were significantly greater than those of the controls at 3 months. The incidences of hepatocellular adenoma in 2,000 ppm core study males and females and of hepatocellular adenoma or carcinoma (combined) in 2,000 ppm core study and 5,000 ppm stop-exposure males were significantly increased. Cholangiocarcinoma occurred in three 5,000 ppm stop-exposure males, and a single hepatocholangiocarcinoma occurred in a 625 ppm male and in a 2,000 ppm core study male. Nonneoplastic lesions of the liver included eosinophilic, mixed cell, and clear cell foci in exposed groups of males and females and mixed cell infiltrate in exposed males and basophilic focus in exposed females. The incidences of alveolar/bronchiolar adenoma and alveolar/bronchiolar adenoma or carcinoma (combined) were significantly increased in 5,000 ppm stop-exposure males, as were alveolar/bronchiolar hyperplasia in most exposed groups of males and females. The incidences of hematopoietic cell proliferation of the spleen and of hyperplasia of the mandibular lymph node (females) and bone marrow were increased in exposed groups of males at 3 months and/or 2 years and in exposed groups of females at 2 years. The incidences of mononuclear cell leukemia were significantly decreased in all groups of males exposed to 1,250 ppm or greater and in all exposed groups of females; the incidence of testicular interstitial cell adenoma was significantly decreased in 5,000 ppm stop-exposure males. 2-YEAR STUDY IN MICE: Groups of 60 male and 60 female mice were fed diets containing 0, 1,250, 2,500, or 5,000 ppm o-nitrotoluene (equivalent to average daily doses of approximately 165, 360, or 700 mg/kg to males and 150, 320, or 710 mg/kg to females) for 105 weeks. Survival, Body Weights, and Feed Consumption: All 2,500 and 5,000 ppm males died before the end of the study. Survival of 1,250 ppm males and 5,000 ppm females was significantly less than that of the controls. Mean body weights of exposed males and 5,000 ppm females were generally less than those of the controls throughout the study, and those of 2,500 ppm females were less during the second year of the study. Feed consumption by 5,000 ppm males was less than that by the controls. Biomarkers of Exposure: Three urinary metabolites were followed during the study as biomarkers of exposure. The ratios of o-nitrobenzoic acid to creatinine determined at 2 weeks and at 3, 12, and 18 months were linearly related to exposure concentration in males and females. The concentrations of o-nitrobenzylmercapturic acid and o-aminobenzoic acid were below the limit of quantitation at most time points. Pathology Findings: The incidences of hemangiosarcoma in all exposed groups of males and in 5,000 ppm females were significantly greater than those in the controls. Large intestine (cecum) carcinomas were observed in all exposed groups except 5,000 ppm males. The incidences of hepatocellular neoplasms were significantly increased in 2,500 and 5,000 ppm females. Nonneoplastic liver lesions including eosinophilic and basophilic foci and minimal to mild necrosis were enhanced in exposed males and females. Also present were focal hepatocyte syncytial alteration in exposed males and hepatocyte necrosis and focal hepatocyte cytoplasmic vacuolization in 5,000 ppm females. Renal tubule pigmentation occurred more frequently in exposed groups of males and in 5,000 ppm females than in the controls. Olfactory epithelial degeneration occurred in every male and female mouse exposed to 2,500 or 5,000 ppm, and the severity of this lesion increased with increasing exposure concentration. GENETIC TOXICOLOGY: o-Nitrotoluene was not mutagenic in any of several strains of S. typhimurium, with or without metabolic activation enzymes (S9). Sister chromatid exchanges were significantly increased in cultured Chinese hamster ovary cells following exposure to o-nitrotoluene in the presence of S9; an equivocal response was seen without S9. o-Nitrotoluene did not induce chromosomal aberrations in cultured Chinese hamster ovary cells, with or without S9. o-Nitrotoluene did not induce a significant increase in the frequency of micronuclei in bone marrow polychromatic erythrocytes of male rats or male mice when administered by intraperitoneal injection. Results of a peripheral blood micronucleus test were equivocal for male mice and negative for female mice administered o-nitrotoluene in feed for 13 weeks. CONCLUSIONS: Under the conditions of these studies, there was clear evidence of carcinogenic activity* of o-nitrotoluene in male rats based on increased incidences of malignant mesothelioma, subcutaneous skin neoplasms, mammary gland fibroadenoma, and liver neoplasms. The increased incidences of lung neoplasms in male rats were also considered to be exposure related. There was clear evidence of carcinogenic activity of o-nitrotoluene in female rats based on increased incidences of subcutaneous skin neoplasms and mammary gland fibroadenoma. The increased incidence of hepatocellular adenoma in female rats was also considered to be exposure related. There was clear evidence of carcinogenic activity of -o-nitrotoluene in male and female mice based on increased incidences of hemangiosarcoma, carcinoma of the large intestine (cecum), and hepatocellular neoplasms (females only). Exposure to o--nitrotoluene caused increased incidences of nonneoplastic lesions of the mammary gland (females only), liver, bone marrow, spleen, lung, and mandibular lymph node (females only) in male and female rats and of the liver, kidney, and nose in male and female mice. Decreased incidences of mononuclear cell leukemia occurred in exposed groups of rats; the incidence of testicular interstitial cell adenoma was decreased in exposed male rats. [tables: see text]

Administration, Oral↗
PubMed1999

DNA ploidy and nuclear morphometry for the classification of dysplastic nevi.

OBJECTIVE: To examine the diagnostic value of DNA ploidy and nuclear morphometric features in sporadic dysplastic nevi as compared to those in compound nevi and melanoma. STUDY DESIGN: DNA ploidy profiles plus seven direct and three derived nuclear features were obtained in a series of 120 melanocytic skin neoplasms (30 dysplastic nevi [DN], 30 melanomas [MM], 60 compound nevi [CN]) and the results compared. RESULTS: DNA ploidy separated melanomas from benign melanocytic skin neoplasms with 96.5% accuracy in classifying the grouped cases. The derived nuclear shape factor Form PE and nuclear axis ratio were the most successful discriminants separating DN from MM but allowed only 73.3% correct classification of cases. Separation of DN from CN was best achieved using Form PE and mean nuclear area (74.4% correctly classified). Results from compound nevi in subjects < 25 years of age fell between those for DN and MM. CONCLUSION: Quantitative nuclear cytologic characteristics in sporadic dysplastic nevi span a range seen in common nevi through to those in thin melanomas. Cytologic changes in sporadic dysplastic nevi overlap those seen in other melanocytic skin neoplasms. Therefore, other reproducible morphometric features need to be assessed in order to further refine the histopathologic diagnosis of this entity.

Adult↗
PubMed2002

Skin tumors in aging Long Evans rats.

We report 25 cases of skin neoplasm observed among 30 Long Evans rats serving as controls in a psychosocial behavioral study conducted in the Vivarium at Charles R. Drew University, Los Angeles, CA. The animals were 10 weeks old at the beginning of the study. All the skin tumors developed at 18 to 26 months of age and slowly enlarged over a period of 9 months. Multiple nodules occurred in 8 males and 6 females. None of the tumors regressed. The tumors were located around the hind leg and dorso-medial area and measured 1 to 2 cm. Physical examination revealed firm well demarcated dermal masses. Most of the tumor nodules were intradermal, and some had a central ulcerated or keratin-filled core. Microscopic examination performed on some of the tumors showed findings of classic Keratoacanthoma, whereas others showed histologic features suggestive of squamous cell carcinoma. These findings indicate a high rate (83%) of spontaneous skin neoplasms among aging Long Evans rats. To our knowledge, such a high rate of skin neoplasms in aged rodents has not been described in the literature. Furthermore, further studies should be undertaken to confirm these findings and to assess whether these rodents might serve as a model for studying the alterations in the immune system with aging.

Aging↗
PubMed2003

Pilomatrixoma: a review of 346 cases.

Pilomatrixoma, also known as calcifying epithelioma of Malherbe, is a benign skin neoplasm that arises from hair follicle matrix cells. Pilomatrixoma is a common skin neoplasm in the pediatric population that is often misdiagnosed as other skin conditions. This study reviews an 11-year experience at a tertiary children's hospital, examining the cause, clinical and histopathological presentation, management, and treatment outcomes of pilomatrixoma. A review of the pathology database at Children's Hospital Los Angeles revealed 346 pilomatrixomas excised from 336 patients between 1991 and 2001. The hospital charts, pathology records, and plastic surgery clinic charts were reviewed with respect to variables such as sex, age at the time of presentation, clinical and histopathological presentation, preoperative diagnosis, management, recurrence, and treatment outcome. The main presenting symptom was a hard, subcutaneous, slowly growing mass. The preoperative diagnosis was accurate and consistent with the pathological diagnosis of pilomatrixoma in only 100 cases (28.9 percent). This entity should be considered with other benign or malignant conditions in the clinical differential diagnosis of solitary firm skin nodules, especially those on the head, neck, or upper limbs. The diagnosis can generally be made with a clinical examination. Imaging studies are not required unless symptoms or the location of the lesion warrants such diagnostic assessments. The treatment of choice is surgical excision, and the recurrence rate is low.

Adolescent↗
PubMed1990

[Colonic neoplasms and skin fibromas: common determinants and their significance].

To find common factors for colonic-neoplasias and skin-tags, 157 inpatients, who consecutively had a coloscopy because of intestinal complaints, were intensively examined dermatologically. Regression-analyses showed that the number of colonic polyps were age- (p = 3 x 10(-8)) and sex-dependent (1.9 x 10(-2)) and skin-tags had no influence on the number of colonic polyps. The size of colonic polyps also showed a clear age dependency (p = 3 x 10(-8)). The number of skin-tags were dependent on weight (p = 9 x 10(-3)) and age (p = 1.3 x 10(-2)), its size on the interaction of sex and triglyceride-levels (p = 3 x 10(-8)). Discriminant-analyses identified the following factors as important: age and triglyceride-concentration to recognize a patient with colonic polyps; age, positive Haemoccult-test and number of skin-tags to recognize a patient with tubulovillous adenomas or colonic carcinomas. The essential common factor of colonic polyps and skin-tags was the age. For the recognition of a patient with colonic polyps the age was the most essential factor, skin-tags, on the contrary, were unimportant. The association between colonic polyps and skin-tags therefore was merely an effect of age.

Age Factors↗