Artikel
Proton radiotherapy in the management of complicated conjunctival melanoma
Suche in Medline nach
Autoren
Veröffentlicht: | 22. September 2004 |
---|
Gliederung
Text
Objective
Primary conjunctival melanomas may be diffuse and involve several parts of the conjunctiva. Recurrences sometimes develop at the site of the primary tumour but very often they spread to other, primarily not affected, parts of the conjunctiva. Proton beam irradiation offers the opportunity to define several, flexible and not necessarily adjacent radiation fields, which gives the possibility to keep sensitive structures, e.g., limbus, lens, posterior segment, out of the irradiated volume.
Methods
Twenty patients with conjunctival melanoma were treated in cooperation with the Centre Antoine-Lacasagne in Nice between 1992 - 2002 with proton beam irradiation. All cases were not assessable for brachytherapy with a plaque. Sixteen cases were recurrences after various pre-treatments. A total of 31Gy in 6 fractions was applied. The "high risk" areas were treated with a boost in 2 fractions up to 45Gy. This corresponds to a biological dose of 52Gy irradiation with photons.
Results
The mean follow-up time is 3.2 years. Recurrent disease occurred in 6 cases (30%); 2 of them outside the radiation field, 3 within the field treated with 31Gy, and a single one in the boost-field of 45Gy. An exenteration followed only in two patients (10%). Among the 18 patients who have their eye preserved the visual acuity remained within one line of change in 12 cases (66.6%); in 14 patients the visual acuity was 0.25 or better. A sicca syndrome developed in 19/20 patients. However, only 8/20 patients use artificial tears more than 5x/d, and just 6 patients (30%) were substantially annoyed by that. A focal cataract developed in 7 patients (35%). Metastatic disease occurred in 6 patients (30%) and so far 4 (20%) of them died. There was no association between the occurrence of local recurrence and the development of metastases.
Conclusions
For cases of complicated and diffuse conjunctival melanomas proton beam irradiation offers an alternative to exenteration.