SAN DIEGO – Using laser and light sources to treat nonaggressive basal cell carcinoma (BCC) is emerging as a promising treatment option, especially for those with multiple tumors and those who are poor surgical candidates, , said at the annual Masters of Aesthetics Symposium.
“Topical therapies often result in recurrence, so there really is a need for an alternative [to surgery] that’s effective, efficient, and carries a low risk of side effects,” said Dr. Ortiz, who is director of laser and cosmetic dermatology at the University of California, San Diego,
“The prototypic feature of BCC is the presence of telangiectatic vessels,” she explained, and the postulated mechanism of action is selective photothermolysis of the tumor vasculature. “These vessels are slightly larger in caliber, compared with normal skin – 40 micrometers versus 15 micrometers – and more fragile. You can tailor your pulse duration to the size of the vessels. Theoretically, by targeting the vasculature then you get tumor regression with sparing of normal tissue.”
Initial studies of this approach have used the 595-nm pulsed-dye laser, which is well absorbed by oxyhemoglobin, but more recent studies have used the 1064-nm Nd:YAG to reach deep arterial vessels. In a prospective, open-label study, 10 patients with 13 BCCs less than 1.5 cm in diameter received one treatment with a 10-ms pulsed 1064-nm Nd:YAG laser delivered on the trunk or extremities at a fluence of 80-120 J/cm2 (). Dr. Ortiz and her colleagues observed a 92% clearance rate overall.
She described other earlier studies of the approach as flawed, because they relied on confirmation of clearance rates with clinical exam or biopsy rather than with surgical excision. “Also, some of the protocols weren’t standardized, multiple treatments were required, and subjects with suboptimal response were currently on anticoagulation,” she said. “Intravascular coagulation is important for effective treatment with vascular lasers, so anticoagulation may interfere with efficacy.”
In a more recent multicenter study, Dr. Ortiz and her colleagues treated 33 BCCs once with the long-pulsed 1064-nm Nd:YAG laser delivered with a 5-6 mm spot size at a fluence of 125-140 J/cm2 and a 7-10 ms pulse duration (). Standard surgical excision with 5-mm margins was performed 4 weeks after laser treatment. Among 31 subjects who completed the study, 28 of 31 BCC tumors (90%) cleared after one treatment.
“The treatments were performed without anesthesia, because we didn’t want the vasculature to be affected, but in clinical practice I am now using lidocaine with no epinephrine,” Dr. Ortiz said. She characterized the results as “at least comparable to, if not superior to” common modalities including methyl aminolevulinate–PDT (72.8%), imiquimod cream (83.4%), and fluorouracil cream (80.1%). “One criticism I hear is that with such high fluences, you’re probably getting some bulk heating,” she said. “Maybe so, but it seems to work and there’s no scarring, which suggests otherwise.”
Advantages of using a 1064-nm Nd:YAG for treating nonaggressive BCCs are that it requires just one treatment, it takes about 5 minutes, and there is no significant downtime, with no limitations in posttreatment activity. “Potentially there is a relatively decreased risk for complications, including infection and bleeding,” she added. “It’s a good alternative for treating patients with multiple tumors or those who are poor surgical candidates.”
She and her colleagues are currently performing a long-term follow-up study of 35 BCC lesions. Only one has potentially recurred, but that recurrence has not yet been confirmed.
Dr. Ortiz treats BCCs with a standard 5-mm margin and uses lidocaine without epinephrine to avoid vasoconstriction. She typically uses a 1064-nmdelivered at a pulse duration of 8 ms and a fluence of 140 J/cm2, with no cooling. “Theoretically, any 1064-nm pulsed-dye laser could work, but the way the pulse is delivered is different, depending on which device” is used, she said.
“I always like waiting between passes to avoid any bulk heating. The immediate endpoint to strive for is slight graying and slight contraction,” she said. Billing codes for malignant destruction/electrodesiccation and curettage can be used (codes 17260-17266 for the trunk and 17280-17283 for the face).
In order to determine the mechanism of cell death and to optimize results, Dr. Ortiz said that further studies need to be conducted in vitro and in vivo. In order to determine treatment efficacy, clinical studies involving various heat sources and low concentrations of lidocaine are also required.
Dr. Ortiz disclosed having financial relationships with numerous pharmaceutical and device companies. She is also cochair of the MOAS.