[Clinical and epidemiological characteristics of squamous cell carcinoma of the oral cavity in women]. / Características clínico-epidemológicas do carcinoma epidermóide de cavidade oral no sexo feminino.

BACKGROUND: Squamous cell carcinoma (SCC) of the oral cavity occurs mainly in the male population. The objective of the study is to identify the main clinical and epidemiological differences of the oral SCC between men and women. METHODS: Retrospective analysis of the charts of 228 cases of SCC of the oral cavity in women treated at the Head & Neck Surgery Service, Heliopolis Hospital, São Paulo, Brazil from 1977 to 1996. The clinical and epidemiological characteristics of these cases were compared with those of 849 male patients. RESULTS: The mean age of women was 60.7 years (ranging 2 to 100 years) and in the male group was 55.6 years (p<0.00001). In cases where the alcohol intake and tobacco use were absent, the tumors ocurred in older patients. The isolated tobacco use didn't affect the distribuction by age but for the alcohol intake (alone or combined with tobacco) the patients were younger. On the alcohol intake, 71% of the women and 8% of the man used no alcohol. The most common sites of tumors were tongue and floor of the mouth but in the women group the incidence of tumors in these sites were 43% compared with 61% in the men. CONCLUSIONS: The highest incidence of SCC the of oral cavity occurs later in women, than in men. This could be explained by a lesser exposure to alcohol and tobacco in women. Other factors seem to be involved in this issue.

Características clínico-epidemológicas do carcinoma epidermóide de cavidade oral no sexo feminino / Clinical and epidemiological characteristics of squamous cell carcinoma of oral cavity in women

OBJETIVO: Este trabalho tem como objetivo identificar as principais diferenças clínico-epidemiológicas do carcinoma epidermóide de cavidade oral no sexo feminino quando comparado ao sexo masculino. MÉTODOS: Foram estudados retrospectivamente os prontuários de 228 pacientes do sexo feminino portadoras de carcinoma epidermóide de cavidade oral, atendidos no Serviço de Cirurgia de Cabeça e Pescoço do Hospital Heliópolis, no período entre 1977 e 1996. As características clínico-epidemiológicas destas pacientes foram comparadas com aquelas de 849 pacientes do sexo masculino. RESULTADOS: A idade das pacientes das mulheres variou de 2 a 100 anos, com uma média de 60,7 anos. Nos homens encontramos idade entre 17 e 88 anos com uma média de 55,6 (p<0,00001). Quando o etilismo e o tabagismo estavam ausentes, a incidência do carcinoma epidermóide de boca ocorreu em uma faixa etária mais tardia. A presença do tabaco isoladamente näo afetou a distribuiçäo por faixa etária, enquanto que o álcool isoladamente ou em associaçäo com o tabaco leva a uma incidência mais precoce do câncer de boca. Os dois principais sítios de incidência säo a língua e o soalho. As mulheres têm uma menor incidência de lesöes de língua e soalho (43 por cento) quando comparado aos homens (61 por cento). Aproximadamente 50 por cento das mulheres eram estadio III e IV no momento do diagnóstico. Entre os homens este índice atinge 53 por cento. CONCLUSÖES: O carcinoma epidermóide de cavidade oral nas mulheres tem características clínico-epidemiológicas peculiares que justificam o desenvolvimento de protocolos de diagnóstico e tratamento específico para ele

Perioperative frozen section examination in parotid gland tumors.

CONTEXT: The minimal recommended surgical approach to parotid tumors is partial parotidectomy with resection of the superficial lobe of the gland. Histologic diagnosis prior to surgery is not possible, as incisional biopsies are contraindicated due to the possibility of facial nerve injury or incomplete tumor resection. Thus, the biopsies tend to be perioperative. OBJECTIVE: To compare the results of frozen section examination with the definitive pathological diagnosis. DESIGN: Accuracy study by retrospective analysis. SETTING: Head and Neck Surgery Service of Heliópolis Hospital, São Paulo, Brazil. SAMPLE: 153 cases of parotid gland tumors treated between 1977 and 1994. DIAGNOSTIC TEST: Frozen section and pathological diagnosis. MAIN MEASUREMENTS: Sensibility and specificity of the frozen section examination. RESULTS: Frozen section study diagnosed 19 (12.4%) malignant and 127 (83.7%) benign tumors. Sensitivity of the frozen sections for malignancy was 61.5% (95% CI 54 to 69%) and specificity was 98% (95% CI 94 to 100%), and this result is comparable to the literature. CONCLUSIONS: We consider that frozen section examination for salivary gland tumors is not sufficient on its own for deciding on the best management. Their interpretation must be correlated with clinical and intraoperative findings, in association with the surgeon's experience.

Head and neck squamous cell carcinoma in childhood.

BACKGROUND: Squamous cell carcinoma (SCC) of the head and neck region is rare in young patients and even less frequent in children 15 years or younger children. The patients reported in the literature are isolated cases and their management is always difficult because there is no large experience or a convincing theory to support treatment decisions for every child. PROCEDURES AND RESULTS: Four patients aged 15 years or younger were treated for SCC of head and neck between 1977 and 1995 at the Head and Neck Service of Heliópolis Hospital, São Paulo, Brazil, and with this paper we are reporting our experience with their treatment, including a genetic investigation in two cases (immunohistochemical analysis using monoclonal antibodies against p53 and c-erbB-2 oncogenes). These patients had no history of tobacco or ethanol abuse and no history of cancer in their families. Many authors attribute an unusual aggressiveness to SCC in childhood, with propensity to locoregional recurrence and high death rates and therefore, propose aggressive multidisciplinary therapy. Our cases, with the exception of one, had an early diagnosis and were treated using the same method we use for adults; the results were very good. CONCLUSIONS: We recommend for these cases the same protocol as for older patients. In these cases, however, the primary lesion is resected with a safety margin which is usually 2 to 3 mm larger than usual safety margins and selective neck dissection is routinely indicated. This management is adopted in an attempt to avoid postoperative irradiation which may prove to be dangerous in the future for young patients. On the other hand, we recognize that due to a small number de patients, definitive treatment recommendations cannot be made at this time.

Specific effects of the benzodiazepine midazolam on visual receptive fields in light and dark adapted human subjects.

Psychophysical experiments in humans have revealed similar characteristics of visual receptive fields as were found in cats and monkeys from retinal ganglion cell recordings. In addition, in some retinal ganglion cells of cats the GABA antagonist bicuculline decreases the activity of the inhibitory surround. These findings led to two predicitions: 1) benzodiazepines will selectively increase the inhibitory surround of human visual receptive fields, 2) after dark adaptation, no free GABA will be available in the synapses and benzodiazepines will have no effect on the visual system. Characteristics of human receptive fields were determined by subthreshold summation: the contrast threshold of a vertical line was measured dependent on the distance of two parallel flanking lines whose contrast was below threshold. Both hypotheses were confirmed: the threshold in the inhibitory region of receptive fields was specifically increased in a dose-dependent manner by midazolam PO (7.5 mg: P < 0.05; 15 mg: P < 0.01). In dark-adapted subjects no effect of midazolam was found. Control experiments with atropine (1 mg IV), sulpiride (100 mg IM), and levodopa (100 mg PO) showed no specific effect. The visual system may be a model to bridge the gap between animal and human psychopharmacology.

Secondary structural changes in globular protein induced by a surfactant: Fourier self-deconvolution of FT-IR spectra.

Conformational changes in ovalbumin, a globular protein, induced by an anionic surfactant, sodium dodecyl sulfate (SDS), have been monitored by an FT-IR spectrometer using ZnSe cylindrical internal reflection optics which allows high quality IR spectra to be obtained in water solution. The most notable change, on addition of SDS, occurs in the composite band of the Amide I absorption band and the vibrational frequency of the composite C = O bond shifts from 1639 cm-1 to 1652 cm-1. On the other hand, the position of the Amide II band remains fairly unchanged. Comparison of the various peak positions in the deconvoluted spectra for the native protein and the perturbed protein clearly shows the effect of SDS on the secondary structures of the protein. SDS unfolds the protein. It increases the helix content slightly. More importantly, it alerts the beta sheet structure, destroying it almost completely in the Amide I region, while retaining it in its neighbourhood. In the deconvoluted spectra of the perturbed protein, a band at 1531 cm-1 indicates generation of some beta turns. We used the second derivative of the deconvoluted spectra for fixing positions of minor peaks and shoulders. The results of this study indicate that the deconvolution of the normal IR spectra, consisting of composite bands, provides evidence for the specific secondary structures in a protein and for the way they are affected by changes in the environment, e.g., the addition of SDS. This makes it possible to relate conformational changes to specific secondary structures.