[An optimal follow-up protocol for renal cell carcinoma based on the occurrence of recurrences after surgery]

The tumor biology of renal cell carcinoma (RCC) remains poorly understood and the prognosis of which is unpredictable. To define an optimal follow-up protocol in nonmetastatic RCC, tumor recurrences and the clinical course were assessed in the patients who had undergone nephrectomy.

Between March 1972 to July 1999, 265 patients with PT1-3N0 (Nx) M 0 RCC underwent radical or partial nephrectomy. Clinicopathological variables were compares with the time of the first recurrence, site of metastasis and reason for diagnosis.

In July 1999, the median (range) follow-up for the surviving patients was 50 (1-244) months. Metastases were diagnosed in 45 of the 265 patients (17%). Sixty percent of the patients had their metastases diagnosed within 3 years and 87% by 6 years. The incidence and the mean time to first diagnosis of recurrence were 9.0% and 43.6 months for pT1, 32.4% and 39.6 months for pT2, and 32.7% and 25.0 months for pT3. Metastatic sites and the mean time of diagnosis were 40.6 months in lung (46.7%), 26.1 months in bone (17.8%), 18.6 months in retroperitoneal organs (11.1%), 38.0 months in liver (6.7%), 51.0 months in thyroid gland (4.4%) and 31.0 months in brain (2.2%). Most recurrence in lung, retroperitoneal organs and liver were incidentally diagnosed, whereas recurrences in bone, thyroid gland and brain had some symptoms associated with metastases. Incidence of lung metastasis in pT1 (9 patients, 56%) and pT2 (6, 55%) was greater than that in PT3 (6, 33%). In contrast, incidence of abdominal metastasis (retroperitoneal organs and the liver) in pT3 (4 patients, 33%) was grater than pT1 (2, 12%) and PT2 (1, 16%).

The results indicate that the risk of tumor progression and site of metastasis seemed to depend on original TNM stage. Therefore stage specific postoperative follow-up protocol should be considered. The yearly follow-up may suffice for pT1a patients after surgery. For pT1b and pT2 patients, the follow-up should be intense during the first 3 years by a routine chest X-ray. For pT3 patients, the follow-up during the first 2 years may be important. Particularly, considering the high incidence of abdominal metastasis in these patients, examination by CT scan is recommended every 6 months in the first 2 years. No need for bone scintigraphy and brain CT was indicated for asymptomatic patients.