Introduction: Among multiple primary cancers in the same patient, renal cell carcinoma occurring either synchronously or metachronously is one of the most common.
Aim: The aim of the study was to determine the frequency of second primary malignant tumor in patients with primary renal cell carcinoma.
Material and methods: Between 1992 and 2000, 447 patients underwent nephrectomy for primary renal tumor at the Department of Urology, Sestre milosrdnice University Hospital. Out of 447 patients 310 were registered at Cancer Registry of the Republic of Croatia. There were data on 297 patients with renal cell carcinoma, 197 male and 104 female patients, age group 24-91 (mean 59.9) years.
Results: Data on 24 (8.1%) patients with second primary malignant tumors were found in Hospital Registry and Croatian Cancer Registry during the study period. There were 13 male patients, age range 47-80 (median 65.1) years, and 11 female patients, age range 51-70 years (median 61.1) years with 26 second primary tumors. One male patient presented with four different primary tumors (kidney, prostate, urinary bladder and colon). The patients most commonly presented with prostate and colon carcinoma. The second malignant primary tumors occurred most commonly as antecedent to renal cell carcinoma, i.e. in 11 (42.3%) cases.
Conclusion: Our results indicate that during the clinical follow-up of patients treated for primary renal cell cancer, a possibility of second primary cancers should always be considered. In order to upgrade detection of multiple cancer, the quality and completeness of cancer notification and registration from hospitals as well as collaboration between the National Cancer Registry and hospital cancer registries should be improved.