Doctors Guide (KC) 10-Mar-09

Go Back To Doctors Guide (KC)

Percutaneous Cryoablation Destroys Small Kidney Tumours: Presented at SIR

SAN DIEGO -- March 10, 2009 -- Percutaneous cryoablation is an effective treatment modality and a viable alternative to more invasive options for renal cell carcinoma in patients with tumours in the 4-cm range, according to research presented here at the Society of Interventional Radiology (SIR) 34th Annual Scientific Meeting.

More than 50,000 individuals were diagnosed in the United States with kidney cancer last year, according to the American Cancer Society. Most of the tumours were found incidentally while undergoing other procedures and tests.

Interventional cryoablation is as effective as partial nephrectomy, the current gold-standard treatment, according to the study's coauthor and presenter Christos Georgiades, MD, PhD, Vascular and Interventional Radiology, Johns Hopkins Hospital, Baltimore, Maryland.

"The good news is that most tumours, when diagnosed, are small and amenable to treatment offered by interventional radiology," said Dr. Georgiades in his presentation on March 9. "Using cryoablation, the major advantages are that there is no incision -- just a tiny hole in the skin -- and no surgery; no general anaesthesia, and the patient is awake and even talking."

Dr. Georgiades said that laparoscopic surgery literally cuts out the tumour and that patients no longer need to have a kidney partially or completely removed to treat their cancer. When asked to compare the rates of complications between percutaneous cryoablation and traditional surgery, he said that none of his patients who had cryoablation developed new or metastatic disease.

In their study, Dr. Georgiades and colleagues assessed the outcomes of CT-guided, percutaneous cryoablation of 90 renal masses in 84 consecutive patients treated over a period of 2.5 years. All patients were referred by the urology department and included both surgical and nonsurgical candidates. Biopsy was performed in all patients prior to or at the time of the cryoablation. In 70% to 75% of presenting patients, the tumour was 4 cm or smaller in dimension. Median age was 67 (range 57-77).

Ablation protocol consisted of a 10-minute freeze, an 8-minute thaw, and a 10-minute refreeze cycle. Ablation needles were placed by an interventional radiologist under image guidance. The procedure took about 28 minutes each with the patient under lidocaine.

Technical success was defined as if the cryoablation "ice-ball" extended at least 4 mm beyond the tumour margins. Follow-up protocol consisted of clinic visits and contrast enhanced CT or MRI at 3, 6, and 12 months, and yearly thereafter. Efficacy was determined based on tumour size and enhancement pattern on follow-up imaging (MRI or CT). Imaging studies were read by an independent radiologist. Overall and disease specific survival were calculated at 1, 1.5, and 2 years.

Results showed a technical success rate of 100% in the patient population studied. Lesion size was 2.5 cm (1-10 cm); 10 of the 73 Bosniak III-IV lesions were benign. For the rest, overall and disease-specific survival was 98.1% and 100%, respectively, at a median follow-up of 45 weeks (12-117).

For the 14 patients followed for a median of 2 years, both overall and disease-free survival rates were 100%. Primary and secondary (reablation) efficacy outcomes based on imaging results were 96.8% and 98.4%, respectively. No patients with disease confined to the kidney developed metastatic disease during the follow-up period.

"The image-guidance option is remarkable as a first treatment option," said Dr. Georgiades. "This treatment can be used on patients with tumours all the way up to 10 cm, and most patients go home from the hospital the same day."

[Presentation title: Percutaneous Cryoablation for Renal Cell Carcinoma: Efficacy. Abstract 19]

To View The Original Article Click Here

Disclaimer

E&OE - Errors & Omissions Excepted