Rain, winds and haze during the Huygens probe's descent to Titan's surface.

The irreversible conversion of methane into higher hydrocarbons in Titan's stratosphere implies a surface or subsurface methane reservoir. Recent measurements from the cameras aboard the Cassini orbiter fail to see a global reservoir, but the methane and smog in Titan's atmosphere impedes the search for hydrocarbons on the surface. Here we report spectra and high-resolution images obtained by the Huygens Probe Descent Imager/Spectral Radiometer instrument in Titan's atmosphere. Although these images do not show liquid hydrocarbon pools on the surface, they do reveal the traces of once flowing liquid. Surprisingly like Earth, the brighter highland regions show complex systems draining into flat, dark lowlands. Images taken after landing are of a dry riverbed. The infrared reflectance spectrum measured for the surface is unlike any other in the Solar System; there is a red slope in the optical range that is consistent with an organic material such as tholins, and absorption from water ice is seen. However, a blue slope in the near-infrared suggests another, unknown constituent. The number density of haze particles increases by a factor of just a few from an altitude of 150 km to the surface, with no clear space below the tropopause. The methane relative humidity near the surface is 50 per cent.

The National Bladder Cancer Group's experience: invasive and metastatic bladder cancer selected reports.

The National Bladder Cancer Group, a multidisciplinary organization that was originally the therapeutic arm of the National Bladder Cancer Project, reported the results of trials using cisplatin with and without cyclophosphamide in patients with advanced bladder cancer. The objective response rate in both arms was 16% of 109 patients with no difference between the arms. Other studies included cisplatin and irradiation for patients who had comorbid conditions that prevented cystectomy (local response--cT2 11/13 patients; cT3 & cT4 2/4 patients). Seventy patients were treated on the same protocol, and 33 were alive 4 years later. Complete response versus local failure produced 57% versus 11% at 4 years. After cessation of funding, the clinicians at the Massachusetts General Hospital agreed to follow a potentially bladder-sparing multimodality protocol, which stipulated that visible tumor be resected following which the patient received methotrexate, vinblastine and cisplatin (MCV), small-volume irradiation, and more cisplatin with midcourse cystectomy if local tumor persisted. Overall survival was 45%. The Radiation Therapy Oncology Group conducted a similar study omitting MCV from one arm. The 5-year survival rate was 38% with no advantage for either arm.

Bladder cancer: race differences in extent of disease at diagnosis.

BACKGROUND: Blacks are less likely than whites to develop bladder cancer; although once diagnosed, blacks experience poorer survival. This study sought to examine multiple biological and behavioral factors and their influence on extent of disease. METHODS: A population-based cohort of black bladder cancer patients and a random sample of frequency-matched white bladder cancer patients, stratified by age, gender, and race were identified through cancer registry systems in metropolitan Atlanta, New Orleans, and the San Francisco/Oakland area. Patients were ages 20-79 years at bladder cancer diagnosis from 1985-1987, and had no previous cancer history. Medical records were reviewed at initial diagnosis. Of the patients selected for study, a total of 77% of patients was interviewed. Grade, stage, and other variables (including age, socioeconomic status, symptom duration, and smoking history) were recorded. Extent of disease was modeled in 497 patients with urothelial carcinoma using logistic regression. RESULTS: Extent of disease at diagnosis was significantly greater in Blacks than in Whites. Older age group, higher tumor grade, larger tumors, and presence of carcinoma in situ were related to greater extent of disease in blacks and in whites. Large disparities between blacks and whites were found for socioeconomic status and source of care. Blacks had greater symptom duration and higher grade. Black women were more likely to have invasive disease than white women; this difference was not seen among men. Blacks in unskilled occupational categories, perhaps reflecting socioeconomic factors, were at much higher risk for muscle invasion than whites. CONCLUSIONS: While specific relationships between variables were noted, an overall pattern defining black and white differences in stage did not emerge. Future studies should examine the basis upon which occupation and life style factors operate by using biochemical and molecular methods to study the genetic factors involved.