Case Presentation
An 8-month-old girl with an unremarkable prenatal and birth history
presented with a giant red nodular lesion on her left shoulder. The
lesion first appeared at 7 weeks of age as a solitary, small
vascular-appearing red papule, not exceeding 1 cm. Two dermatologists
diagnosed it as an infantile hemangioma with no systemic involvement. No
treatment was initiated due to its location, lack of ulceration, and
small size. The parents were advised to monitor the lesion, anticipating
typical growth and spontaneous regression.
At 8 months of age, the infant was brought to the emergency department
with fever and lethargy. Routine blood tests revealed pancytopenia and
elevated C-reactive protein levels. A peripheral blood smear showed a
few blast cells (Fig. 1b), leading to admission for severe neutropenic
fever.
During hospitalization, the lesion on the left shoulder had grown to 16
cm (Fig. 1a). Examination revealed a highly erythematous, giant nodular
lesion that was firm on palpation with overlying ulceration. No bruit or
thrill was detected on auscultation, and Doppler ultrasound showed no
vascular malformation. Bone marrow and skin biopsies were performed
under general anesthesia.
The skin biopsy revealed perivascular atypical large lymphoid cells
infiltrating the dermis (Figure 2a), and immunohistochemistry confirmed
B cells via positive terminal deoxynucleotidyl transferase (TdT) and
CD20 markers (Fig. 2b). The bone marrow biopsy confirmed acute B-cell
lymphoblastic leukemia. The diagnosis of leukemia cutis secondary to
B-ALL was established. The patient was promptly started on induction
chemotherapy (vincristine,dexamethasone, asparaginase, and doxorubicin),
and the skin lesion drastically regressed in size after the first cycle
(Fig. 2c), demonstrating a positive response to treatment.