Ultrasound screening for renal cell carcinoma is feasible but not clearly justifiable

In a two-year study involving nearly 10,000 volunteers, German researchers have found that using ultrasonography to screen for renal cell carcinoma is effective, but its justification remains unclear.

In the May issue of BJU International, the multicenter team led by Dr. Dragana Filipas at the University of Mainz, Germany, reports that 9,959 volunteers who were at least 40 years old underwent 17,810 renal ultrasound exams during the course of the study. When subjects underwent follow-up ultrasound exams 1 year after their baseline exams, the sensitivity of the test was 82%, and the predictive value was 2% for equivocal findings and 50% for positive findings. Renal masses were discovered in 13 patients. Nine of these masses turned out to be renal cell carcinoma. On the basis of older registry data, the authors had expected to identify 3 cases of renal cell carcinoma per 10,000 subjects, rather than the 9 cases they observed. They point out, however, that the proportion of late stage, larger tumors was high. “Early detection by screening did not lead to a shift toward lower tumour stages, one of the key goals of screening,” they write. Only 6 of their patients had low-stage tumors and were thus likely to benefit from screening. During the period of the study, 481 patients were admitted to the researchers’ hospitals with renal tumors. In only 2% of these patients had the tumor been identified by the screening program, according to the investigators. “The screening programme was well accepted by physicians in private practice and by the eligible population,” according to the authors. Even so, they conclude, “Whether the…benefit will justify the cost of screening…can only be answered in a comparative prospective long-term screening study of a screened and unscreened population.” Dr. Filipas and colleagues add that cost factors vary by country. “In the USA, for example, renal ultrasound is reserved for the radiologist and is thus much less accessible…[and] many times more costly.” (Source: BJU International 2003;91:595-599: Reuters Health: May 29, 2003: Oncolink)