Post-operative radiation-induced hyperpigmentation remains a concern in keloid treatment. 

A new study published in Der Hautarzt aimed to identify clinical features and risk factors of superficial X-ray-induced hyperpigmentation in postoperative keloid radiotherapy.

Here, 70 keloids in 55 patients were treated with superficial X-ray after surgery between 2019-20. Follow-up photographs were taken one month after radiotherapy; clinical characteristics and severity of pigmentation were summarized. 

The findings revealed that the pigmentation was a well-defined rectangular brown macule consistent with the unprotected area that involves the normal skin. While 82.9% of keloids displayed pigmentation induced by superficial X-ray – at one month after treatment. All keloids of the trunk appeared to be mild-to-moderately hyperpigmented and 92.89% of limb keloids displayed severe pigmentation. On the other hand, keloid location was an independent risk factor for the incidence and severity of pigmentation. In addition, longer incision length was predictive of increased severity of hyperpigmentation.

It was inferred that superficial X-ray-induced hyperpigmentation was common and severe in postoperative keloid radiotherapy. The location and incision length of the keloid are associated with the incidence and severity of pigmentation.

Source: Journal of Cosmetic Dermatology. 2021 Jun 21. doi: 10.1111/jocd.14308.