An 80+ year old white male presented to clinic with history of a non-healing, easily friable patch on the left lower back for years. He reports having a left nephrectomy with prior radiation in 1997. Exam revealed a 2.5cm x 5 cm erythematous plaque with telangiectasia and central ulceration. A biopsy was taken. Clinical and pathologic presentation below:
What is the cause of this patient’s plaque?
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DIAGNOSIS & CASE SUMMARY:
This patient was diagnosed with chronic radiation dermatitis. Pathology was consistent with the diagnosis showing epidermal atrophy with underlying superficial and mid dermal sclerosis and loss of adnexal structures. There are numerous stellate fibroblasts and dilated thin walled blood vessels within the eosinophilic collagen. The clinical history and histologic findings are consistent with chronic radiation dermatitis.
Radiation dermatitis often presents a few weeks to years post external beam radiation for malignancies, as in this patient’s case, but can also be a result of radiation exposure from interventional radiology procedures such as angiography and catheter placement. Exposure of the skin to radiation results in tissue injury with resultant epidermal damage. Doses greater than 55 Gy increase risk of skin damage. Typical radiation dermatitis is sharply demarcated, confined to exposed skin areas. Radiation dermatitis is generally classified as acute vs chronic. Acute radiation dermatitis occurs within three months of initial radiation exposure, and the skin typically shows erythema and desquamation with occasional ulceration. Chronic radiation dermatitis occurs much later, up to 10 years post exposure. This patient’s presentation is typical: atrophic plaques with telangiectasia and friable skin. Patients must be followed closely for not only ulceration, but also development of secondary skin cancers in the radiated areas.
The ulceration was treated and an x-ray was taken to r/o bone necrosis. No necrosis was noted, but the patient had a minimally displaced rib fracture and was referred to his primary physician for further evaluation and treatment of the fracture. He was followed closely to be sure the ulceration was healing. We discussed excision of the area, but since the central ulceration healed appropriately, we are awaiting further treatment unless the area becomes symptomatic. Regular skin checks are scheduled to monitor for development of secondary skin cancers.
BY: Amy John, PA-C, Dr. Eric Hanson, Dr. Kelli Hutchens and Dr. Betsy Wernli