Immunoglobulin light-chain amyloidosis in the setting of multiple myeloma diagnosed from oral biopsy

Immunoglobulin light-chain (AL) amyloidosis, the most common clinical form of systemic amyloidosis, is a serious condition that may affect the oral mucosa. Although macroglossia is the most common manifestation, other oral mucosal sites may be involved. This case report describes AL amyloidosis diagnosed by oral biopsy in a patient who was subsequently found to have multiple myeloma.

A 58-year-old woman sought treatment because of multifocal oral nodules, fatigue, weight loss, shoulder and low back pain, congestive heart failure, chronic anemia, cough, episodes of vision loss, proteinuria, and neuropathy in the hands. Oral biopsy confirmed the presence of amyloid deposition, and the workup established a diagnosis of AL amyloidosis in the setting of λ light-chain multiple myeloma. Six months after the initiation of treatment with daratumumab, cyclophosphamide, bortezomib, and dexamethasone there was a 46-fold decrease in free serum λ light chains. The patient reported less fatigue, improvement in appetite, and weight gain despite persistent macroglossia. After several treatment modifications, hematologic response was achieved with elranatamab, despite adverse events.

AL amyloidosis is a complex, potentially life-threatening condition that requires a multidisciplinary approach. This article highlights the role of the dentist in facilitating the diagnosis through a simple oral biopsy. Since dentists are often the first specialists to encounter oral manifestations of systemic disease, heightened awareness is crucial for timely recognition and referral.