Efficacy and Safety of Intralesional Cryosurgery Alone and in Combination With Intralesional 5-fluorouracil/Triamcinolone Acetonide Injection for Treatment of Keloids: a Comparative Clinical Study

Keloids are abnormal scars characterized by excessive collagen deposition that extends beyond the original wound boundaries, often leading to cosmetic disfigurement, pain, pruritus, and tenderness, significantly affecting patients' quality of life . Keloid formation is influenced by genetic predisposition, skin tension, wound location, and inflammatory responses, and they are notorious for high recurrence rates, with some reports indicating recurrence in up to 50-80% of cases after treatment .

Various therapeutic modalities have been used for the management of keloids. These treatment options can be broadly classified into intralesional therapies, topical therapies, and procedural interventions.

Despite the availability of multiple treatment options, no single therapy ensures complete resolution, and recurrence remains a significant challenge in keloid management .

Intralesional corticosteroids remain the first-line therapy, reducing fibroblast proliferation, collagen synthesis, and local inflammation. Clinical studies have shown flattening of keloids in 50-70% of patients with repeated injections . Another commonly used intralesional agent is 5-fluorouracil (5-FU), an antimetabolite that inhibits fibroblast proliferation and extracellular matrix deposition, with reported improvement in 70-80% of cases . Combination therapy of corticosteroids and 5-FU has demonstrated superior efficacy compared with monotherapy.

Among procedural modalities. Intralesional (IL) cryotherapy, is a technique in which a cryogen can be applied using a cryoneedle directly into the deeper dermis of the scar to produce rapid scar freezing from the core outwards, thus all the pathological tissue will be frozen and destructed, creating a new scar without keloidal characteristics, while sparing the surface epithelium. As a monotherapy, IL cryosurgery has yielded promising clinical results in terms of volume reduction and alleviation of pain and pruritus . Marked efficacy of a single intralesional cryosurgery session has been recorded even in voluminous keloids, which is an additional major advantage compared with the repeated sessions required in classical contact cryosurgery, However, on average, no complete scar eradication is attained and scar recurrence is seen. Also, persistent hypopigmentation remains problematic in nonwhite patients . These issues raise the question whether IL cryotherapy could be used in combination with nonsurgical therapies to augment the therapeutic effect and to lower the risk of hypopigmentation.