Prospective nonrandomized analysis of treatment method.
PARTICIPANTS: Of 100 consecutive patients with choroidal
melanoma treated with transpupillary
thermotherapy, the mean
tumor basal diameter was 7.1 mm and
tumor thickness was 2.8 mm. The
tumor margin touched the optic disc in 34 eyes (34%) and was beneath the fovea in 42 eyes (42%). Documented growth was present in 64 eyes (64%), and known clinical risks for growth were present in all of the remaining 36 eyes (36%), with an average of 4 of 5 statistical risk factors for growth per
tumor. After a mean of three treatment sessions and 14 months of follow-up, the mean
tumor thickness was reduced to 1.4 mm. Treatment was successful in 94 eyes (94%) and failed in 6 eyes (6%). Three patients with amelanotic
tumors showed no initial response to
thermotherapy, but subsequent intravenous
indocyanine green administration during
thermotherapy resulted in improved heat absorption and
tumor regression to a flat
scar. The six eyes classified as treatment failures included four eyes with
tumors that showed partial or no response to
thermotherapy, thus requiring plaque
radiotherapy or enucleation, and two eyes with recurrence, subsequently controlled with additional
thermotherapy.
After treatment, the visual acuity was the same (within 1 line) or better than the pretreatment visual acuity in 58 eyes (58%) and worse in 42 eyes (42%). The main reasons for poorer vision included treatment through the foveola for subfoveal
tumor (25 eyes),
retinal traction (10 eyes),
retinal vascular obstruction (5 eyes),
optic disc edema (1 eye), and unrelated ocular
ischemia (1 eye). Temporal location (versus nasal and superior, P = 0.02) and greater distance from the optic disc (P = 0.04) were risks for
retinal traction.
CONCLUSIONS: Transpupillary
thermotherapy may be an effective treatment for small posterior choroidal
melanoma, especially those near the optic disc and fovea. Despite satisfactory local
tumor control, ocular side effects can result in decreased vision. Longer follow-up will be necessary to assess the impact of
thermotherapy on ultimate local
tumor control and metastatic disease.