如何优化瘢痕疙瘩核素贴片治疗？3D打印精准剂量技术解析

Keloids are a type of pathological fibroproliferative disease that occurs after skin trauma. They are characterized by the continuous proliferation of scar tissue beyond the original wound boundaries, invading surrounding normal skin and forming hard, raised masses. Clinically, they often present with persistent itching and pain, and in severe cases, can ulcerate [1,2]. The pathological features include sustained inflammatory reactions, overexpression of growth factors, increased fibroblast proliferation and myofibroblast activation, excessive deposition of collagen and extracellular matrix, increased angiogenesis, and reduced apoptosis [3]. This condition is more common in adolescents and individuals aged 20 to 30 years [1]. Currently, clinical treatments for keloids include medications, surgery, and radionuclide patch therapy, but each has its limitations [4]. Medications have significant individual variability, numerous adverse effects with long-term use, and poor patient compliance [5]. Simple surgical treatment has a high recurrence rate [4]. Ferdinand W et al. [6] conducted a two-year follow-up study on 90 patients who underwent surgical excision followed by postoperative radiotherapy for keloids. The results showed an overall recurrence rate of 21%, with potential gender differences: the recurrence rate was as high as 31% in male patients and only 12% in female patients. Radionuclide patch therapy requires strict dose control, and traditional methods lack precision in conformity and dose regulation, leading to complications such as radiation dermatitis, hypopigmentation or hyperpigmentation, and skin atrophy [7]. To overcome the limitations of traditional radionuclide patch therapy in terms of dose precision and conformity, this study focuses on optimizing radionuclide patch treatment. The principle of this treatment involves encapsulating radionuclides such as ³²P and 90Sr-90Y within a patch that adheres closely to the surface of the lesion, using the β-rays emitted during radionuclide decay to irradiate superficial lesions at close range [8]. ³²P has a physical half-life of 14.3 days and emits β-rays with an energy of approximately 1.71 MeV, which have an average range of 4 mm in human tissue and a maximum range of 8 mm [9]. 90Sr has a physical half-life of 28.5 years and decays into the daughter nuclide 90Y, which has a physical half-life of 64.2 hours. 90Y decays by emitting β-rays with an energy of 2.274 MeV, which have an average range of 2.5 mm and a maximum range of 10.3 mm in tissue [9]. When β-rays act on the lesion, they produce ionizing radiation effects, slowing down the division rate of fibroblasts in the lesion and extending their cell cycle, ultimately effectively inhibiting abnormal tissue proliferation [10] (Figure 1). Among these, ³²P is preferred for most superficial lesion treatments due to its moderate half-life and higher clinical availability. Compared to ³²P, 90Y has higher β-ray energy and deeper tissue penetration, making it suitable for treating recalcitrant keloids [10]. To address the issue of poor conformity in traditional radionuclide patches, Jingyu Wang et al. [11] used machine learning and 3D printing mold technology to develop customized ³²P hydrogel (HG) patches, achieving precise morphological conformity to the two-dimensional contours of the lesion, significantly enhancing clinical applicability. However, this approach did not consider the three-dimensional thickness characteristics of the lesion and lacked radiological dosimetry evaluation. To address this problem, this study obtained three-dimensional data of the lesion through 3D scanning, directly 3D printed hydrogel patches, and conducted radiological dosimetry studies to accurately cover the lesion area and minimize damage to normal tissues, providing new insights for precise radiotherapy of keloids. Based on this, we further validated the therapeutic effects of this personalized custom radionuclide patch at the organoid level in other superficial proliferative diseases such as infantile hemangiomas and genital warts, demonstrating its broad application prospects in the field of universal precision radiotherapy.