title: [Nephron-sparing surgery for the treatment of small renal tumors. The role of radiofrequency].
abstract: OBJECTIVE
  Laparoscopically assisted radiofrequency is a minimally invasive nephron-sparing treatment option for renal tumors, mainly in patients with high comorbidity. We present the short-term results of our series patients treated with this novel technique.
  
  
  METHODS
  Renal lesions smaller than 4 cm, suspicious of malignancy or metastasis on CT scan or MRI are candidates for radiofrequency. Under laparoscopic vision the tumor is identified, and percutaneous biopsy is performed. Depending on the size of the tumor, a number of punctures with the radiofrequency needle are performed with the aim to achieve tumor necrosis during at least one cycle of radiofrequency. Follow-up is performed with MRI in the first postoperative day and then after CT scan or MRI at 1, 3, 6 and 12 months. The persistent absence of contrast or vascular necrosis of the lesion is considered a satisfactory ablation without recurrence.
  
  
  RESULTS
  12 patients, two with metastasis and ten with primary lesions (mean age 60.8 years), with one or more lesions suspicious of malignancy underwent radiofrequency. Mean ASA was 2.4. 15 tumors were treated, with a mean diameter of 2.8 cm. An average of 2.5 punctures was performed with the radiofrequency needle. Biopsy results showed: one case of thyroid cancer metastasis, one case of melanoma metastasis, and 10 cases of renal cell carcinoma. Mean hospital stay was 25.8 hours. There were not short-term complications. Follow-up time was 8.8 months. Today there is no evidence of recurrence in imaging tests.
  
  
  CONCLUSIONS
  Radiofrequency is effective eradicating small renal lesions, both primary and metastatic; it is especially useful in patients with high comorbidity. Despite the number of patients with adequate follow-up is not enough, the technology is promising. The approach under laparoscopic vision contributes to an effective biopsy, avoiding dissemination and enabling a more precise radiofrequency by direct vision control of tumor necrosis.
authors.affiliation: Unidad de Enndourología y laparoscopía Urológica, Clínica Santa María, Santiago, Chile.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Velasco
authors.forename: Octavio
authors.initials: O
authors.lastname: Castillo
authors.forename: Ivar
authors.initials: I
authors.lastname: Vidal
authors.forename: Rafael
authors.initials: R
authors.lastname: Sánchez-Salas
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Campos
authors.forename: Renato
authors.initials: R
authors.lastname: Cabello
authors.forename: Felipe
authors.initials: F
authors.lastname: Balbontin
authors.forename: Alejandro
authors.initials: A
authors.lastname: Majerson
authors.forename: Gilberto
authors.initials: G
authors.lastname: González
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017115:Catheter Ablation / Q000379:methods; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D009399:Nephrons; D011446:Prospective Studies; D055815:Young Adult