(BMJ)—A child presented with this firm, immobile, and painless lump over the right eyebrow. The lump wasn't warm to touch. It had developed gradually following an injury to the area 3 months previously and had persisted despite topical antibiotics. What's the dx?
lymphoblastic lymphoma
basal cell carcinoma
frontal sino-cutaneous fistula
orbital cellulitis
You are correct. Excisional biopsy and immunohistochemical staining revealed B-lymphoblastic lymphoma. Lymphoblastic lymphoma is a highly aggressive non-Hodgkin’s lymphoma which most commonly affects children. Skin involvement in lymphoblastic lymphoma is seen in fewer than 2% of cases, and usually presents as a large solitary tumor in the head and neck region. Cutaneous manifestations may grow rapidly and have accompanying systemic symptoms such as fever, weight loss, and night sweats, although this child didn't experience any of these.

BMJ 2023;382:e073394