title: Multiple ipsilateral renal tumors discovered at planned nephron sparing surgery: importance of tumor histology and risk of metachronous recurrence.
abstract: OBJECTIVE
  Unrecognized sporadic multifocality at planned nephron sparing surgery (NSS) presents a surgical dilemma. We report a single institution experience with patients presenting with multiple ipsilateral renal tumors, of which at least 1 was renal cell carcinoma (RCC). We determined the outcome for patients treated with NSS or radical nephrectomy (RN).
  
  
  METHODS
  A total of 118 patients underwent surgery between 1970 and 2000 for sporadic multiple ipsilateral renal tumors, of which at least 1 was RCC. The patients were treated with RN (102) and NSS (16). Clinical features recorded included age at surgery, sex, history of smoking, a preexisting solitary kidney and symptomatic disease at presentation. Pathological features included histological subtype, nuclear grade, tumor stage (2003 TNM) and tumor size. Cancer specific survival was estimated using the Kaplan-Meier method.
  
  
  RESULTS
  A greater proportion of patients treated with NSS had a solitary kidney compared with patients treated with RN (6 or 38% versus 0, p <0.001). Of the 102 patients treated with RN for multiple tumors 12 died of RCC at a median time to death of 3.3 years (range 3 months to 9.5 years). Estimated cancer specific survival at 5 years was 90.1%. There was metachronous contralateral recurrence in 5 patients a median of 8.1 years following RN (range 3 months to 14 years). Two of the 16 patients treated with NSS died of RCC 6 and 11 years following NSS, respectively, for a cancer specific survival rate of 100% at 5 years. Two patients had local renal recurrence 1.7 and 2.8 years following NSS, respectively, and a metachronous contralateral renal tumor was found in 1 patient 7 months following NSS. Of the 102 patients treated with RN 63 (62%) and 9 of the 16 (56%) treated with NSS had at least 1 clear cell RCC. In 23 of the 102 patients (23%) treated with RN only 1 tumor was RCC, while the remainder were benign, suggesting that these patients were potential candidates for NSS.
  
  
  CONCLUSIONS
  Patients undergoing RN or NSS for multiple ipsilateral renal tumors, of which at least 1 is RCC, have favorable cancer specific survival. The metachronous contralateral recurrence rate for patients with sporadic multifocal lesions is approximately 5%. Planned NSS may not be abandoned if satellite lesions are benign.
authors.affiliation: Department of Urology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Michael  L
authors.initials: M
authors.lastname: Blute
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Thibault
authors.forename: Bradley C
authors.initials: BC
authors.lastname: Leibovich
authors.forename: John C
authors.initials: JC
authors.lastname: Cheville
authors.forename: Christine M
authors.initials: CM
authors.lastname: Lohse
authors.forename: Horst
authors.initials: H
authors.lastname: Zincke
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D016609:Neoplasms, Second Primary / Q000601:surgery*; D009392:Nephrectomy / Q000379:methods; D012189:Retrospective Studies