An unusual oral manifestation of chronic lymphocytic leukemia: A case report and review of the literature.

Background: Chronic lymphocytic leukemia (CLL) is the most prevalent type of leukemia in adults, characterized by the accumulation of mature-appearing, immunologically dysfunctional B lymphocytes in the blood, bone marrow, and secondary lymphoid organs. Oral manifestations of CLL are infrequent and less documented. The authors present a case of CLL in remission with multiple lesions of the palatal mucosa and a literature review of all reported cases of oral manifestations of CLL.

Case description: A 75-year-old woman with hereditary hemochromatosis, hypogammaglobulinemia, and CLL in remission on ibrutinib sought treatment for multiple, asymptomatic, erythematous papules of the palatal mucosa incidentally noticed by her general dentist. A complete blood count revealed mild absolute lymphocytosis. Extraoral examination was unremarkable. A biopsy of 1 of the palatal mucosa lesions was obtained. Histopathologic examination revealed a focus of B-cell CLL, supported by immunohistochemistry showing the cells positive for cluster of differentiation 5, cluster of differentation 43, PAX-5, BCL-2, and LEF-1. The patient's hematologist-oncologist ruled out ibrutinib resistance due to Bruton tyrosine kinase (BTK) or PLCG2 mutations. Ibrutinib treatment was continued, and at the 1-year follow-up, only erythema of the palatal mucosa was observed.

Practical implications: Oral health care providers should include CLL in the differential diagnosis for multiple erythematous papules of the palatal mucosa, particularly in the presence of absolute lymphocytosis. Early recognition of oral manifestations associated with CLL can prompt a timely referral.