5 Year Follow-up Results of Periocular Basal Cell Carcinoma Nitrous Oxide Cryotherapy
A recent report in the British Journal of Opthalmology focuses on what is believed to be the first report on the 5-year follow-up of the outcome of nitrous oxide contact probe cryotherapy for treatment of primary periocular basal cell carcinomas. Let’s unpack that.
A Look at Cryotherapy, in Brief
+ rapid freeze and slow thaw at temperatures below -30°C
+ freezing agents include liquid nitrogen, nitrous oxide and carbon dioxide
+ reported cure rates for liquid nitrogen therapy vary between 92% and 100%
The Study Stats
+ 100 periocular basal cell carcinomas in 95 patients
+ all carcinomas were >8mm in diameter
+ 58 females, 37 males; median age of 71 years
+ 36 of the 95 cases were not completed (15 death, 12 relocation, 9 lost and untraceable)
The Kaplan-Meier method was used to accommodate follow-up losses, so percentages relate to the 59 cases that were not lost. Of those cases, 94% of the treated basal cell carcinomas were recurrence-free at 36 months. At 60 months, 92% cases were recurrence-free. Histological method proved the recurence rate at 5 years to be 8%.
Results show that nitrous oxide probe cryotherapy is effective for clinically diagnosed primary periocular basal cell carcinomas measuring up to 8 mm diameter. It is simple and attractive to patients in its low side-effects and non-surgical nature.
Researchers are still asking, however, if a recurrence rate of 8% is acceptable. While there is not a 100% clearance rate, it is still one of the more popular treatments and if selected, should involve follow-up for as long as 5 years, if possible.
[image by Chris Samuel]