Purpose
To describe the histopathological features of amyloid deposition seen in the ocular surface and/or adnexa biopsy specimens and further characterize the type of amyloid with proteomic analysis.
Methods
This is a retrospective study in which the medical records from patients that were diagnosed with primary and secondary ocular and orbital amyloid deposition at our institution were retrieved between 1991-2014. The demographic data, clinical findings and pathology reports were also reviewed. Mass spectrometry-based proteomic analysis was performed in one case using formalin-fixed paraffin-embedded tissue.
Results
The study included 9 patients (5 females, 4 males). The mean age was 59.1 years (range 39 - 88 years). Eight cases presented as unilateral lesions in otherwise healthy patients and one case was bilateral, in a patient with a previous history of multiple myeloma confirmed by electrophoresis. Four cases involved the conjunctiva, three cases with lesions in the eyelid and two cases presented as orbital masses, one of them with ptosis. Congo red stain was positive in eight cases; one case was unequivocal but moderately positive for Thioflavine T. Proteomic analysis performed in one of the orbital masses demonstrated lambda light chain-derived peptides (but not kappa). Systematic clinical evaluation in this patient was performed, and no evidence of a systemic plasma cell dyscrasia was identified.
Conclusions
Our study describes the clinicopathologic features of amyloid deposition in the ocular surface and adnexa in patients with no evidence of predisposing disease, as well as secondary amyloid orbital deposition seen in one patient with a preexisting plasma cell dyscrasia (multiple myeloma). Proteomic analysis may be of value in biopsies from these patients and deserves further study.