Thymectomy and RCC Incidence: Exploring the Link

Regina Barragan-Carrillo, MD, medical oncologist, postdoctoral fellow, Department of Medical Oncology and Therapeutics Research, City of Hope Comprehensive Cancer Center, discusses results of a study which sought to assess the association between thymectomy and incidence of renal cell carcinoma (RCC).

Transcription:

0:09 | For the end points that we tested for the rate of nephrectomies, or renal serve diagnosis specifically, how we did this and how we chose that is because of the methodology we had available. We used the [California Office of Statewide Health Planning and Development (OSHPD)] database, which is the standard for the office of statewide planning and development which is a database based in California, which accounts for all the procedures that are done in the in an outpatient setting, and also for [emergency room] visits. What we have seen with the information available are the procedures through the CPT and ICD-9/10 coding.

0:49 | What we decided is to use the coding for thymectomy and the coding for nephrectomy to identify both groups. For example, the rate we have in the state of California accounting for all adult patients, meaning 40 years or older, the rate we have for nephrectomy for renal cell carcinoma is around 0.2%. The rate we noticed in those patients who have previously undergone a thymectomy was 0.56%, which is more than double than we would have expected for the state of California.

1:26 | One might raise the question, and I think it is a valid question, whether there was a risk of bias in the selection of the population because these are patients who are already under certain scrutiny because of their past surgical history, so we included in our analysis, another 3 surgical procedures, which were a cholecystectomy, a hip arthroscopy, and a knee arthroscopy, and in all of 3 subpopulations who had undergone those procedures and afterwards required nephrectomy for RCC, the rates for RCC re diagnosis were also pretty similar to what we saw in the overall population, which were around 0.20%. Historically, the numbers make sense in that regard, and the difference between the patients with a prior thymectomy was quite clear to us.