Sir,

Conjunctival mucosa-associated lymphoid tissue (MALT) lymphomas are localized low-grade extra-nodal tumours that are managed with radiotherapy, cryotherapy, surgical excision, or even observation.

Intra-lesional interferon injection for conjunctival lymphomas was first cited as early as 1996 by Cellini et al;1 its successful use has been reported since then.2, 3 We report a case where its use has been invaluable in a patient with recurrent conjunctival MALT lymphoma following external beam radiation.

Case report

A 55-year-old woman presented with a 2-week history of red watery right eye and swelling of her right lower lid. On examination, she had a salmon pink mass in the right inferior bulbar conjunctiva (Figure 1a). The rest of the ocular examination was normal. Conjunctival biopsy confirmed this to be an extra-nodal marginal-zone MALT-type lymphoma. The patient was treated with external beam radiation (24 Gy in 12 fractions) to the right inferior conjunctiva with complete regression of the lymphoma.

Figure 1
figure 1

(a) Digital photograph of the right inferior conjunctival lesion at presentation. (b) Digital photograph of the right superior conjunctival lesion 10 months post external beam radiation. (c) Haematoxylin and eosin-stained section of the recurrent lesion showing diffusely packed atypical lymphoid cells. (d) Immunohistochemistry with CD20 showing membranous staining of the lymphoid cells indicative of a B-cell lymphoma. (e) Digital photograph of the right conjunctival lesion 1 month post interferon injection demonstrating complete regression of the lymphoma.

Full size image

At 10 months post radiotherapy, she was noted to have a similar pink lesion in the right superior bulbar conjunctiva (Figure 1b). A biopsy confirmed recurrent MALT lymphoma (Figure 1c).

Owing to recent external beam radiotherapy it was felt inappropriate to re-treat her with the same modality and she was treated with intra-lesional interferon injection.

She received a 4-week course of 3 times a week intra-lesional injections of 1.5 mega-units in 0.25 ml of Interferon α2A, with complete regression of the lesion.

She remains disease free at 10 months follow-up.

Comment

Radiotherapy has been widely used as a treatment for MALT lymphoma with successful results, but ocular complications such as corneal ulcers, radiation-induced cataract, ocular surface disorders,4 and recurrence have been reported.

Intra-lesional interferon has been successfully used for treatment of conjunctival MALT lymphoma. A recurrence rate of 15% on a long-term follow-up (65 months) has been reported.5

We believe this is the first case reported where intra-lesional Interferon α2A was used in recurrent conjunctival MALT lymphoma after external beam radiation, and we recommend considering it in similar cases.