Effect of retinoids on the induction of colon cancer in F344 rats by N-methyl-N-nitrosourea or by 1,2-dimethyihydrazine

The possible modifying effect of synthetic and natural retinoidson the incidence of colon cancer in rats induced by 2 intrarectaldoses of 2.5 mg of N-methyl-N-nitrosourea (MNU) given once aweek for 2 successive weeks or a single 150 mg/kg body weightdose of 1,2-dime-thylhydrazine (DMH), s.c. was investigated.Emphasis was on the effect of the development of early tumorsas visualized by endoscopy. With the retinoids N-ethyl-retinamide,N-2-hydroxyethylretinamide, N-(4-hydro- xyphenyl)-all-trans-retinamide(RAHA), and retinyl acetate (RA) administered orally after thecarcinogens, significant differences in early developing tumorswere not found. At histopathological examination of the tumorsthe RAHA + DMH group had significantly fewer adenomas per animal.The percentage of adenoma bearing rats was significantly lowerin groups receiving RAHA + DMH or RA + DMH. However, food consumptionwas lower in rats consuming either RAHA or RA. Retinyl palmitate(RP) and RAHA was administered intrarectally to MNU-inducedrats either before or after the carcinogen. When administeredbefore MNU, RP caused a significant increase in the percentageof tumor bearing animals and the average number of tumors peranimal as visualized endos copically. At histopathological examination,all retinoid groups except RAHA given after the carcinogen,produced significantly more adenomas per animal and a significantlygreater adenoma incidence than did the control groups. Thus,in two systems, the oral administration of retinoids did notclearly inhibit the early or later stages of colon tumor development.Inirarectal infusion of two retinoids had no effect on colonicmor phology but at histopathological examination of later stagetumors there was an enhanced adenoma response.     

Biopsy findings after breast conservation therapy for early-stage invasive breast cancer

PURPOSE: To determine the patterns and factors predictive of positive ipsilateral breast biopsy after conservation therapy for early-stage breast cancer. METHODS AND MATERIALS: We performed a retrospective review of Stage I-II breast cancer patients initially treated with lumpectomy and radiotherapy between 1977 and 1996, who later underwent post-treatment ipsilateral breast biopsies. RESULTS: A total of 223 biopsies were performed in 193 treated breasts: 171 single and 22 multiple biopsies. Of the 223 biopsies, 56% were positive and 44% were negative for recurrence. The positive biopsy rate (PBR) was 59% for the first and 32% for subsequent biopsies. The median time to the first post-treatment biopsy was 49 months. Of the patients with negative initial biopsy findings, 11% later developed local recurrence. The PBR was 40% among patients with physical examination findings only, 65% with mammographic abnormalities only, and 79% with both findings (p = 0.001). Analysis of the procedure type revealed a PBR of 86% for core and 58% for excisional biopsies compared with 28% for aspiration cytology alone (p = 0.025). The PBR varied inversely with age at the original diagnosis: 49% if >or=51 years, 57% if 36-50 years, and 83% if 180 months after completing postlumpectomy radiotherapy (p = 0.01). The PBR was not linked with recurrence location, initial pathologic T or N stage, estrogen receptor/progesterone receptor status, or final pathologic margins (all p >or= 0.15). CONCLUSION: After definitive radiotherapy for early-stage breast cancer, a greater PBR was associated with the presence of both mammographic and clinical abnormalities, excisional or core biopsies, younger age at the initial diagnosis, and longer intervals after radiotherapy completion.     

Neurocognitive function in same-sex twins following focal radiation for medulloblastoma

Increased neurotoxicity and poor long-term neurocognitive outcome of preschool children treated for brain tumors have led to innovative therapeutic strategies in order to delay or avoid the use of craniospinal radiation and to improve survival. Because these protocols are relatively new, few data exist regarding cognitive outcome. We conducted a twin case-control study to investigate neurocognitive and behavioral outcome in a preschool patient who was 16 months old at diagnosis of medulloblastoma and was treated with surgery, chemotherapy, stem cell transplant, and focal radiation to the tumor bed. Stability and change over two assessments were compared for the patient and her nonaffected twin for standardized measures of cognitive function and experimental measures of parent-child interaction, social competence, and goal-directed play. A striking finding was improvement in intelligence, receptive language, and visual-motor functioning in the affected twin from 12 months to 24 months after treatment. Improvement in ratings of parent-child interaction and social competence for the affected twin was also evident. These findings are notable compared with the potentially devastating impact of craniospinal tumor, and this study is among the first to document the relative benefit of focal radiation in sparing cognitive function, albeit in a single case study.     

Ductal carcinoma in situ: biology, diagnosis, and new therapies

The incidence of ductal carcinoma in situ (DCIS) has markedly increased as a result of the use of screening mammography. Whether DCIS is a premalignant lesion or a cancer remains a cause of debate, but evidence supports the idea that DCIS evolves into invasive breast cancer based on histologic patterns, similar risk factors, and genetic similarities. Microcalcifications identified during mammography generally raise the suspicion of DCIS, and biopsy, often by core needle, confirms such a diagnosis. The extent of disease can be further delineated by breast magnetic resonance imaging. Radiation therapy in breast-conserving treatment, along with tamoxifen, decreases the overall rate of local recurrence in patients with DCIS. Studies in the treatment of DCIS exploring partial breast radiation and trastuzumab are under way. Ongoing investigations with comparative genomic hybridization suggest that there are independent, evolutionary genetic pathways within DCIS. Genome-wide microarray-based gene expression analyses are now providing new opportunities to discover genes that are specifically activated or inactivated during the course of breast cancer progression.     

Evaluation of the implementation of CIPESC in Curitiba

This report of experience has the objective of presenting the results of the evaluation workshops on the implantation of an operating system of CIPESC, which simultaneously describes, validates, quantifies and qualifies the nursing practices in collective health carried out in the scope of extra-internment in the Units of Health of the city of Curitiba, in the State of Paraná. The workshops provided subsidies for identification of the strong points and the difficulties of implementing the CIPESC-Curitiba nomenclature, but at the same time revealed contradictions in the nurses' speeches. It is agreed upon that it is through conscious practice that these contradictions are overcome, and, starting from them, is built a Nursing with potential of intervention in the population's epidemiological profiles.