[Cancer of the kidney, prognostic value of nuclear grading for the early diagnosis of metastasis]. / Cancer du rein, valeur pronostique du grade nucléaire pour le diagnostic précoce de métastase.

ABSTRACT

OBJECTIVES: Since immunotherapy or surgery can sometimes lead to remission of metastatic renal cell carcinoma, it is important to recognize factors predicting metastasis. We therefore evaluated the usefulness of nuclear grading in predicting metastasis of renal cell carcinoma. METHODS: We retrospectively reviewed 95 patients (69 males, 26 females; mean age 63.9 years) who successively underwent surgical exeresis of a renal cell carcinoma. The TNM classification was established on the basis of preoperative work-up (thoraco-abdominal computed tomography, bone scintigraphy) and pathology examination of the surgical specimen. Nuclear grading was performed by a pathologist who was unaware of the histology results. Outcome was evaluated on the basis of physical examination and computed tomography results 6 months after surgery. RESULTS: There were 34 cases of clear cell carcinoma, 10 granulosus tumours, 2 oncocyte tumours and 16 renal cell carcinomas of undetermined type. Mean tumour diameter was 70.3 +/- 37.8 cm. Tumour classification gave (< 5 cm, n = 23; > 5 cm, n = 26; local invasion, n = 28; invasion of neighbouring organs, n = 2). Metastases had been identified in 11 patients before surgery. Nuclear grading according to the Führman scale gave F1 (n = 3), F2 (n = 28), F3 (n = 34) and F4 (n = 24). Tumour size and the TNM classification were correlated with the observed nuclear grading scores. Within one year of surgery, metastasis was observed in 6 patients whose Führman grades were F3 (n = 1) and F4 (n = 5). Metastasis occurred in 26% of the patients with a Führman grade 4. CONCLUSION: Nuclear grading can be used to identify patients who should be closely followed after surgical removal of renal cell carcinoma in order to improve early diagnose of metastasis.