Given the task definition and input, reply with output. Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Hospital case volume has been shown to be a predictor of patient mortality for treatment for various cancers. The influence of hospital case volume on malignant melanoma survival and treatment utilization is unknown.', 'We used the Surveillance, Epidemiology, and End Results-Medicare linked databases to identify patients aged 65 years or older diagnosed with metastatic melanoma between 2000 and 2009. We analyzed claims data to ascertain cancer treatment variation by hospital case volume. Overall survival was evaluated using propensity score methods.', 'Among 1438 patients, 612 (42.6%) were treated in low-volume hospitals (5 patients) after receiving their diagnosis, 479 (33.3%) were treated in intermediate-volume hospitals (6 to 10 patients), and 347 (24.1%) were treated in high-volume hospitals (>10 patients). In Cox proportional hazards models, treatment in a high-volume hospital after propensity score adjustment was associated with a significant improvement in survival when adjusting for other characteristics (intermediate volume: hazard ratio [HR]=0.70, P=0.0007; high volume: HR=0.63, P<0.0001). Patients treated in high-volume hospitals were less likely to receive chemotherapy, surgery, and/or radiation therapy after a metastatic melanoma diagnosis.
Does hospital Case Volume be Associated With Improved Survival for Patients With Metastatic Melanoma?