Track

Case Reports

Abstract

The differential diagnosis for acral eruptions in oncologic therapy commonly includes acral erythema/hand-foot syndrome (HFS) and hand-foot skin reaction (HFSR). HFS, a form of toxic erythema of chemotherapy, presents as red, painful hands due to cytotoxic chemotherapy.  HFSR is characterized by hyperkeratotic plaques or bullae on pressure-bearing sites and is classically due to kinase inhibitors. Both conditions demonstrate vacuolar degeneration and dyskeratosis on pathology. While these are common, it is important to recognize when an acral medication reaction does not fall into these categories, as demonstrated by our case. A 60-year-old woman with B-cell acute lymphoblastic leukemia presented with erythematous, pruritic acral plaques two weeks after starting blinatumomab, a bispecific T-cell engager. She was also receiving ponatinib, a tyrosine kinase inhibitor, and had cytotoxic chemotherapy two months prior. Histopathology demonstrated epidermal spongiosis around acrosyringia without dyskeratosis or eccrine gland involvement. An eczematous eruption due to blinatumomab was favored based on lack of pain, hyperkeratosis, or bullae, time since cytotoxic chemotherapy administration, and presence of only spongiosis without dyskeratosis on pathology. In addition, spongiotic eruptions have been reported with blinatumomab. Recognizing when an acral eruption is not HFS or HFSR is important as high-grade HFS and HFSR necessitate dose reduction. Eczematous eruptions can be treated conservatively with topical steroids - which provided relief for our patient - and dupilumab for refractory cases. The outcome of this case emphasizes the importance of careful medication history, symptom review, and clinicopathologic correlation when approaching acral eruptions in the setting of oncologic treatment.