RÉSUMÉ
Objective To investigate the clinical features,diagnosis,treatment and prognosis of the renal secondary tumor.Methods From January 2000 to January 2014,the data from 31 patients,including 23 male patients and 8 female patients,with renal secondary tumors were analyzed retrospectively.Their mean age was 56 years old (ranging from 38 to 75 years old).The 31 renal secondary tumors rooted in lung cancer(n =14),lymphoma(n =5),colorectal cancer and gastric cancer(n =3),breast cancer(n =2),esophageal cancer(n =1),thyroid cancer (n =1),cervical cancer (n =1) and bladder cancer (n =1),respectively.There were 22 patients (71.0％) of renal metastasis accompany with other organs or lymph node metastasis.9 cases (29％) suffered with independent renal metastasis and 21 cases (67.7％) suffered with unilateral renal metastasis.5 cases(16.1％) were diagnosed as primary tumor with the renal metastasis at the same time,and the remaining 26 cases were found renal metastasis within 9 to 72 months after primary tumor (mean 30 months).There were only 5 patients (16.1％) with symptom.Ultrasound showed low echo range in 20 cases (65.6％) or uneven echo in 11 cases (34.4％).CT showed equal density (77.4％) in 24 cases or slightly low density shadow (22.6％) in 7 cases,most of which were endogenous,mild enhancement.10 cases (32.3％) were bilateral renal metastasis,unilateral renal multiple metastases was found in 6 cases (19.4％),and single metastasis was noticed in 15 cases (48.4％).The average diameter of the renal metastasis was 2.7 cm (ranging from 0.9 to 6.8 cm).Except 4 cases gave up the treatment,the remaining 27 cases were accepted comprehensive therapy about the primary tumor.the 9 patients with renal metastasis only were treated with chemotherapy or targeted therapy for the advanced primary tumor.Among the 9 patients,6 cases were undergone NSS or radical nephrectomy (RN) treatment.Results In 9 cases with only renal metastasis,6 cases,treated by surgery,recovered well.Postoperative pathological and immunohistochemical results confirmed the renal metastasis.Up to January 2015,the follow-up duration ranged from 2 months to 60 months [mean (22.6 ± 18.4) months].The survival time ranged from 1 month to 51 months [mean (13.2 ± 13.2) months].Among 22 cases with multiple metastasis,4 cases gave up treatment,whose average survival time was (2.0 ± 1.4) months.However,the average survival time in remaining 18 cases was (11.1 ± 4.7) months (P ＜ 0.05).In 9 cases with independent renal metastasis,the average survival time in 6 cases,accepted the procedure,was (26.2 ± 18.6) months.While,the average survival time in remaining 3 non-surgical cases,was (10.3 ± 4.0) months (P ＜ 0.05).Conclusions Renal secondary tumor was rare in clinic.Most cases have isolated lesion.Renal secondary tumor was advanced manifestation of the primary tumor,which could prolong the survival time according to the comprehensive treatment for the primary tumor.Surgical resection of the lesion before the comprehensive treatment could be chosen in the independent renal metastasis.