We report the recurrence of a localized conjunctival lymphoma arising in mucosal-associated lymphoid tissue (MALToma) in the psoas muscle, 18 months after initial treatment with radiotherapy. Findings from systemic investigations demonstrated MALToma recurrences in the psoas muscle and the stomach. Ocular adnexal MALTomas typically manifest as localized tumors, which respond well to radiotherapy, but a proportion may recur in typical MALT sites. To our knowledge, this is the first report of a recurrence in the psoas muscle, and the clinical implication is that all patients with ocular adnexal lymphomas need to be followed up for an indefinite period.
Lymphomas originating in muscosal-associated lymphoid tissue (MALToma) are characterized by small B-cell lymphocytes of low-grade malignancy. MALToma was first described in the mucosal tissue of the stomach; other documented sites include the lung, the salivary gland, and the thyroid gland. An ocular adnexal MALToma may involve the eyelids, conjunctiva, or orbital or lacrimal structures. MALTomas are thought to have an indolent natural history and respond well to radio-therapy. However, they may recur and the site of recurrence may be another typical MALT site. We report a case of localized conjunctival MALToma recurring in the psoas muscle and gastric mucosa conjunctive tissue.
A 59-year-old man was referred for an assessment of a small lump on his right conjunctiva, which had been noted 4 months earlier and was not associated with pain or any other ophthalmic symptoms. There was no other remarkable medical history. Results of an ophthalmic examination revealed a small, flesh-colored, mobile mass (2×1.5 cm) on the right superior bulbar conjunctiva.
No regional lymphadenopathy was detected and findings from a systemic examination were normal. An excision biopsy was performed and findings from histopathologic examination revealed an atypical lymphoid infiltrate composed of uniform, small round and small cleaved lymphocytes with occasional larger cells, which are characteristic of extranodal low-grade B-cell lymphoma of MALT type (Figure 1, A). The occasional lymphoepithelial island infiltrated by lymphocytes is also seen in Figure 1. Immunohistochemical staining with L26 identified many B lymphocytes while fewer T lymphocytes stained with CD3 and immunophenotypic analysis demonstrated κ light chain restriction. Staining with CD21 did not demonstrate the remnants of any reactive follicles. Staging investigations (including bone marrow biopsy and computed tomographic scans) confirmed that the disease was localized to the conjunctiva (stage I).
Photomicrographs of biopsy materials that show a polymorphous mixture of small cleaved lymphocytes of mucosal-associated lymphoid tissue (MALTomas). A, Conjunctival biopsy material showing a lymphoepithelial island that has been infiltrated by lymphocytes (arrow) (hematoxylin-eosin, original magnification ×200). B, Psoas muscle biopsy material that shows diffuse infiltration with uniform, small round and small cleaved lymphocytes, typical of MALTomas (a). Some striated muscle fibers are also seen (b) (hematoxylin-eosin, original magnification ×40). C, Gastric polyp biopsy material showing similar diffuse infiltration of gastric lamina propria with a polymorphous mixture of small round and small cleaved lymphocytes as seen in parts A and B (arrows) (hematoxylin-eosin, original magnification ×100).
The patient was successfully treated with low-dose local radiotherapy (27 Gy in 13 fractions), but 18 months later he complained of persistent epigastric pain and on clinical examination had left lower limb edema. Results of a complete blood cell count and a bone marrow biopsy were normal, while the computed tomographic scan of his abdomen revealed a large retroperitoneal mass arising from the left psoas muscle (Figure 2). Further procedures included a gastroscopy, during which a biopsy specimen of a gastric polyp was obtained and computed tomography–guided biopsy of the retroperitoneal mass was performed. The histological features of the gastric polyp and the psoas muscle demonstrated a diffuse infiltrate of small round and small cleaved lymphocytes consistent with MALToma and were identical to the original ocular histologic features (Figure 1). A chemotherapy regimen consisting of 5 cycles of intravenous methotrexate (1 g), bleomycin sulfate (8 mg), doxorubicin hydrochloride (Adriamycin) (89 mg), and cyclophosphamide (1.2 g) was begun. The patient was free of disease at 18-month follow-up.
Computed tomographic scan of the abdomen showing a mass arising from the left psoas muscle (patient in prone position). Pointer is biopsy needle in psoas muscle (a).
Extranodal marginal zone B-cell lymphomas (MALTomas) occur at various sites, most commonly the gastrointestinal tract, salivary gland, lung, and thyroid gland.1 MALTomas affecting the ocular adnexa are not only limited to the conjunctiva or lacrimal apparatus (ie, tissues with mucosal surfaces) but also the diagnosis is based on typical histological changes that can be seen in all ocular adnexal tissues.2,3 Ocular adnexal MALTomas are primarily low-grade lymphomas that are usually confined to the adnexa at diagnosis (stage I) and that respond well to local radiotherapy.3,4 While this is, to our knowledge, the first report of recurrence in the psoas muscle, ocular adnexal MALTomas, like other MALTomas, may recur at typical MALT sites. The tendency to spread to typical locations may be due to specific circulation and homing patterns characteristic of lymphocytes.1 However, MALTomas may arise in any site in the body secondary to autoimmune disease or infection, as typified by patients with Helicobacter pylori infection in whom MALTomas of the gastric mucosa develop.5 Our patient, however, had no history of either autoimmune disease or infection. If appropriate staging procedures show stage I disease, local radiotherapy is still the treatment of choice for primary ocular adnexal MALTomas,3,4 but regular follow-up is required, probably for an indefinite period, as these tumors can transform into diffuse large B-cell lymphomas.3
Accepted for publication September 22, 1997.
Corresponding author: Mark T. Cahill, MD, FRCOphth, The Royal Victoria Eye and Ear Hospital, Adelaide Road, Dublin 2, Republic of Ireland.
Cahill MT, Moriarty PA, Kennedy SM. Conjunctival ‘MALToma' With Systemic Recurrence. Arch Ophthalmol. 1998;116(1):97-99. doi:10.1001/archopht.116.1.97