RESUMEN
The literature is briefly summarized as to how several nutrients affect immune function, susceptibility to infection, and cancer susceptibility or progression. Nutritional deficiencies can impair immunity and so influence susceptibility to infectious agents, including ones that are common and relatively virulent in acquired immune deficiency syndrome (AIDS) patients. A variety of nutrients affect several of the immune functions that are defective in human immunodeficiency virus (HIV)-infected individuals. For example, beta-carotene increased the number of CD4+ cells; vitamin E decreased the number of CD8+ cells and increased the CD4+/CD8+ ratio; vitamin D decreased the CD4+/CD8+ ratio; and iron increased the number of peripheral lymphocytes in humans receiving supplementation. Furthermore, nutritional deficiencies can influence gastrointestinal function, while infectious diseases can influence nutrient requirements by altering the efficiency of absorption and the rate of tissue metabolism. Malnutrition, depressed serum zinc levels, and intestinal nutrient malabsorption have been found in AIDS patients. The above findings suggest that dietary manipulations might diminish the immune defects in HIV infection and enhance resistance to opportunistic infections. However, dietary alterations in immune defects are generally not well quantified and may be small relative to the magnitude of the defects observed in AIDS patients. Because conflicting or adverse effects have been reported for some nutrients, recommendations for dietary supplementation in HIV-infected individuals are premature and possibly hazardous. Further studies are much needed to relate dietary nutrient intakes to clinical outcomes.
Asunto(s)
Seropositividad para VIH/inmunología , Trastornos Nutricionales/inmunología , Humanos , Parasitosis Intestinales/inmunología , Masculino , Neoplasias/inmunología , Fenómenos Fisiológicos de la NutriciónRESUMEN
The purpose of this case-control study was to identify susceptible subgroups, primarily based on pigmentary characteristics, at higher risk of developing melanoma when exposed to the sun. The study group, which was interviewed from 1979 to 1982, consisted of 289 consecutive patients with melanoma and 527 randomly selected controls without cancer. In general, the risk of melanoma associated with sun exposure was greater for individuals expected to be susceptible on the basis of poor ability to tan, but not other pigmentary traits. There were, in addition, some noteworthy interactions between age and sun exposure. Among subjects with poor tanning ability, the risk of melanoma associated with outdoor occupation was more than 3-fold [odds ratio (OR) = 3.3] compared to indoor occupation. In contrast, the analogous OR was much less elevated among subjects with a good ability to tan (OR = 1.5). Mixed indoor and outdoor job exposure was protective among good tanners (OR = 0.80), but not among poor tanners (OR = 1.5). A similar pattern was seen for recreational sun exposure and, when applying multiple logistic regression, for the patient's overall subjective assessment of his lifetime sun exposure. However, quantitative assessment of average hours of sun exposure did not prove to be a good indicator of melanoma risk, even among susceptible individuals. A history of severe sunburn with blistering was associated with nearly 3-fold risk among poor tanners (OR = 2.9) but was protective among good tanners (OR = 0.79). A history of nonmelanoma skin cancer or solar keratosis was a very strong risk factor (OR = 7.3), which, however, did not significantly differ in magnitude among susceptibility subgroups.
Asunto(s)
Melanoma/etiología , Neoplasias Cutáneas/etiología , Luz Solar/efectos adversos , Adulto , Susceptibilidad a Enfermedades , Métodos Epidemiológicos , Color del Ojo , Femenino , Color del Cabello , Humanos , Masculino , Melanoma/etnología , Persona de Mediana Edad , Factores de Riesgo , Neoplasias Cutáneas/etnología , Pigmentación de la PielRESUMEN
The purpose of this case-control study was to identify differences in risk factors between melanoma and non-melanoma skin lesions. The study group, interviewed from 1979 to 1982, consisted of 289 subjects with melanoma, 75 subjects with non-melanoma sun-related skin lesions and 527 controls. Simultaneous comparison of the three subgroups was accomplished by polychotomous logistic regression. The highest exposure category of lifetime sun exposure was associated with a nearly threefold risk of both melanoma and non-melanoma. Poor tanning was associated with an approximately twofold risk of both disease types. Similarly, northern European ethnicity was associated with an approximately twofold risk of disease. Number of moles on the body exhibited a relationship with melanoma only: having more than 25 moles, compared to their absence, was associated with a thirteenfold risk of melanoma. History of freckling was associated with a twofold risk of melanoma, but no increase in the risk of non-melanoma. Alternatively, mixed indoor-outdoor recreational exposure was associated with a 50% increased risk of non-melanoma, but a 25% decreased risk of melanoma. History of severe sunburn was associated with a twofold risk of non-melanoma only. For history of prior sun-related lesions the nearly sevenfold risk of melanoma was exceeded by the 14-fold risk of non-melanoma.
Asunto(s)
Melanoma/etiología , Enfermedades de la Piel/complicaciones , Neoplasias Cutáneas/etiología , Quemadura Solar/complicaciones , Luz Solar/efectos adversos , Estudios de Casos y Controles , Europa (Continente) , Color del Cabello , Humanos , Melanoma/etnología , Recreación , Análisis de Regresión , Factores de Riesgo , Neoplasias Cutáneas/etnologíaRESUMEN
Medical conditions related to hormonal abnormalities were investigated in a case-control study of breast cancer among women who attended a screening centre. Information was obtained by telephone interview regarding physician-diagnosed medical conditions such as thyroid or liver diseases, diabetes, and hypertension, as well as hirsutism, acne, galactorrhoea, and reproductive, menstrual, and gynaecological factors. Results are presented for 354 cases and 747 controls. Women with fertility problems who never succeeded in becoming pregnant were at significantly increased breast cancer risk (adjusted odds ratio [OR] = 3.5; 95% confidence interval [CI]:1.1-10.9). An elevated cancer risk was also associated with having excess body hair (OR = 1.5; 95% CI:1.0-2.3), or having excess body hair in addition to persistent adult acne (OR = 6.8; 95% CI:1.7-27.1). Recurrent amenorrhea (OR = 3.5; 95% CI:1.1-11.5), and a treated hyperthyroid condition (OR = 2.2; 95% CI:1.1-4.4) were significantly associated with risk. A non-significant elevation of risk was present for endometrial hyperplasia (OR = 1.8; 95% CI: 0.8-4.0). There was a suggestion of an association between a history of galactorrhoea and breast cancer risk (OR = 2.0; 95% CI:0.8-4.9) among premenopausal women. No associations were found with other medical or gynaecological factors. The possibility that some of these findings are due to chance cannot be excluded because of the problem of multiple comparisons.
Asunto(s)
Neoplasias de la Mama/epidemiología , Aborto Espontáneo/complicaciones , Acné Vulgar/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/etiología , Estudios de Casos y Controles , Femenino , Enfermedades de los Genitales Femeninos/complicaciones , Hirsutismo/complicaciones , Humanos , Infertilidad Femenina/complicaciones , Ciclo Menstrual , Persona de Mediana Edad , Ciudad de Nueva York/epidemiología , Embarazo , Factores de Riesgo , Encuestas y Cuestionarios , Enfermedades de la Tiroides/complicacionesAsunto(s)
Melanoma/epidemiología , Neoplasias Inducidas por Radiación/epidemiología , Pigmentos Biológicos/fisiología , Neoplasias Cutáneas/epidemiología , Rayos Ultravioleta , Adulto , Factores de Edad , Anciano , Humanos , Masculino , Melanoma/etiología , Persona de Mediana Edad , Neoplasias Inducidas por Radiación/etiología , New York , Riesgo , Factores Sexuales , Neoplasias Cutáneas/etiología , Luz SolarRESUMEN
Some possible explanations are considered for the better response to surgical adjuvant chemotherapy in premenopausal than in postmenopausal breast cancer patients. Mean estrogen receptor (ER) concentration is lower in premenopausal women. It is proposed that ER-negative women tend to respond more favorably to chemotherapy for breast cancer because higher estrogen levels in this group may induce hydrolytic enzymes which break down the stromal barrier to the tumor, resulting in a less viscous, less fibrous stroma, and an increased vascular supply. These conditions may facilitate the diffusion of chemotherapeutic agents to the interior of a tumor. This hypothesis can be investigated utilizing existing data gathered in clinical trials of adjuvant chemotherapy.
Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Receptores de Estrógenos/análisis , Neoplasias de la Mama/análisis , Neoplasias de la Mama/cirugía , Colágeno/metabolismo , Estrógenos/sangre , Estrógenos/farmacología , Femenino , Humanos , Hidrolasas/metabolismo , Menopausia , Invasividad Neoplásica , Pronóstico , Receptores de Estrógenos/metabolismoRESUMEN
In this update, 15 additional successful transanal repairs followed for one to six years postoperatively for low rectovaginal fistulas without colostomies are added to the uniformly successful 20 patients presented in a 1978 report. Changes in perioperative routines have greatly enhanced cost efficiency and these modifications are enumerated. The repair still encompasses total excision of the epithelialized fistula, and reapproximation of the attenuated septal fibers and anal sphincter mechanism, as well as the caudad rectal mucosal advancement that covers and protects the repair from the fecal stream and the high intraluminal pressures of defecation. Once again, we have excluded inflammatory, neoplastic, and irradiation-caused fistulas from this discussion, although we, as well as others, have applied this technique in selected cases.
Asunto(s)
Fístula Rectovaginal/cirugía , Adulto , Canal Anal , Femenino , Estudios de Seguimiento , Humanos , Mucosa Intestinal/cirugía , Tiempo de Internación , Métodos , Membrana Mucosa/cirugía , Cuidados Posoperatorios , Cuidados Preoperatorios , Colgajos QuirúrgicosRESUMEN
Spasm of the proximal sigmoid colon has been a major hindrance in the use of the EEA stapler in low anterior resections. Intravenous glucagon, by causing rapid relaxation and hypotonicity of the sigmoid colon, appears to help correct this problem and allows for a safer and more atraumatic anastomosis.
Asunto(s)
Colon Sigmoide/cirugía , Glucagón/uso terapéutico , Enfermedades del Sigmoide/prevención & control , Espasmo/prevención & control , Engrapadoras Quirúrgicas , HumanosRESUMEN
The benefits of circular stapling devices are obvious. The introduction of staplers with detachable anvils has simplified the stapling procedure even more than the original instruments. A simple technique for placing the anvil and pursestring are described.
Asunto(s)
Colon/cirugía , Recto/cirugía , Engrapadoras Quirúrgicas , Anastomosis Quirúrgica/métodos , HumanosRESUMEN
A cohort of 2,657 infants in Rochester, New York, who were given x-ray treatment for a purported enlarged thymus gland, along with 4,833 siblings, have been followed by mail surveys through about 1986, which represents an average of 37 years of follow-up, to determine their incidence of thyroid cancer. Estimated thyroid doses ranged from 0.03 to > 10 Gy, with 62% receiving > 0.5 Gy. There were 37 pathologically diagnosed thyroid cancers in the irradiated group and five in the sibling controls. The dose-response relation was essentially linear, with no evidence of an additional dose-squared component. The estimated relative risk at 1 Gy was 10 (90% confidence interval 5-23). Thyroid cancer rates were elevated even at low doses; i.e., a dose-response analysis over the range of 0-0.3 Gy showed a significant positive slope. The risk ratio was declining over time but was still highly elevated to at least 45 years after irradiation. An examination of potential risk factors showed that older age at first childbirth was significantly associated with thyroid cancer risk. An evaluation of interactions between possible risk factors and radiation suggested that Jewish subjects and women with older ages at menarche or at first childbirth were at greater risk for radiogenic thyroid cancer.
Asunto(s)
Neoplasias Inducidas por Radiación/epidemiología , Hiperplasia del Timo/radioterapia , Neoplasias de la Tiroides/epidemiología , Factores de Edad , Estudios de Casos y Controles , Relación Dosis-Respuesta en la Radiación , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Lactante , Judíos , Modelos Lineales , Masculino , Factores de Riesgo , Neoplasias de la Tiroides/etiologíaRESUMEN
A retrospective study was done comparing the rates of local recurrence in cancer of the rectum treated by low anterior resection using the stapling device or hand-sewn. It was found that there was no increase in recurrences when the stapler was used, even though lower lesions were treated.
Asunto(s)
Adenocarcinoma/cirugía , Recurrencia Local de Neoplasia/etiología , Neoplasias del Recto/cirugía , Engrapadoras Quirúrgicas , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Estudios RetrospectivosRESUMEN
PURPOSE: A prospective study of colorectal cancer (1987-1991) using flow cytometry was performed to determine the relationship of age with DNA index (DNA-I), sites of disease, Dukes stage, grade, and survival. METHODS: The flow cytometry was performed on 138 fresh, unfixed, surgical specimens using 4',6'-diamidino-2-phenylindole, a DNA fluorochrome. RESULTS: The mean age was 66.9 (42.8 percent > or = 70; range, 22-92; median, 68) years, and 48.6 percent were female. The patients' stages were (in percent): A, 4.4; B, 53.0; C, 38.2; D, 4.4. Tumor grades of differentiation (in percent) were well, 14.4; moderate, 68.9; poor, 16.7; and sites (in percent) were: rectum, 19.6; sigmoid/left, 50.7; transverse/right, 29.0. Aneuploidy (DNA-I not equal to 1.0; CV, 3.5 percent) was found in 58.8 percent. Age (by decade of presentation) was compared with site and Dukes stage. Older patients had more transverse/right-sided lesions (P = 0.003). Patients with Dukes C and D tumors had a lower age (by decade of presentation) than patients with B2 lesions (P = 0.03). Age was not related to DNA-I or grade or DNA-I with sex, grade, site, stage, or survival (P > 0.05). CONCLUSIONS: This prospective study suggests that colorectal cancer tends to present at an earlier stage and in the more proximal colon in the older population. Because right-sided lesions are beyond the reach of sigmoidoscopy, these findings have prognostic and screening implications.