Secondary extraocular extension of choroidal melanoma following primary photodynamic therapy
摘要
Secondary extraocular extension (SEOE) following conservative treatment of choroidal melanoma (CM) is extremely rare, and its occurrence in patients treated with primary photodynamic therapy (PDT) has not been documented in the literature so far. We present three cases from our combined experience in the United Kingdom (UK).
MethodRetrospective, observational case series. All cases of patients treated with PDT, based on the TAP protocol with some deviations, for CM who experienced SEOE were included, from two of the four national ocular oncology centres in the UK. Clinical, radiological, histopathological, and surgical procedural data are presented.
ResultsIn total, at two of the four national ocular oncology centres in the UK, only three patients previously treated with PDT for CM were observed to develop SEOE during their follow up. All patients were treated with PDT after extensive counselling of all treatment options. All displayed local tumour control following initial treatment. SEOE occurred at a mean of 42.3 months [range 24–66] after treatment. SEOE was identified following enucleation for suspected intraocular clinical recurrence, or on surveillance ocular imaging (US and MRI). During ongoing follow up, two patients developed liver metastases, one remains metastasis-free to date. Given our combined experience, the estimated incidence of SEOE of choroidal melanoma following PDT was 1.3–1.6% across two ocular oncology services in the United Kingdom.
ConclusionsLocal radiotherapy remains the mainstay of treatment for small CM due to its superior local tumour control rates. Prior to this study, there had been no reports of SEOE following PDT for CM, so surveillance for recurrence was not designed to detect this complication. This series establishes that SEOE is a rare but important potential risk following PDT, and patients should be both counselled of this, and monitored for it. We suggest that long term follow-up of these patients should include interval ocular ultrasound to monitor for local recurrence and SEOE. Going forward, it may be appropriate to limit the use of primary PDT to those who would otherwise decline treatment of their melanoma.