Foti Pietro Valerio, Inì Corrado, Broggi Giuseppe, Farina Renato, Palmucci Stefano, Spatola Corrado, Liardo Rocco Luca Emanuele, Milazzotto Roberto, Raffaele Luigi, Salamone Vincenzo, Caltabiano Rosario, Puzzo Lidia, Russo Andrea, Reibaldi Michele, Longo Antonio, Vigneri Paolo, Venturini Massimo, Giurazza Francesco, Avitabile Teresio, Basile Antonio
Department of Medical Surgical Sciences and Advanced Technologies "G.F. Ingrassia", University of Catania -Radiology I Unit, University Hospital Policlinico "G. Rodolico-San Marco", Via Santa Sofia 78, 95123 Catania, Italy.
Department of Medical Surgical Sciences and Advanced Technologies "G.F. Ingrassia"-Section of Anatomic Pathology, University of Catania, Via Santa Sofia 87, 95123 Catania, Italy.
Cancers (Basel). 2022 Jan 2;14(1):215. doi: 10.3390/cancers14010215.
Necrosis in uveal melanomas can be spontaneous or induced by radiotherapy. The purpose of our study was to compare the histopathologic and MRI findings of radiation-induced necrosis of a group of proton beam-irradiated uveal melanomas with those of spontaneous necrosis of a control group of patients undergoing primary enucleation. 11 uveal melanomas who had undergone proton beam radiotherapy, MRI and secondary enucleation, and a control group of 15 untreated uveal melanomas who had undergone MRI and primary enucleation were retrospectively identified. Within the irradiated and nonirradiated group, 7 and 6 eyes with histological evidence of necrosis respectively, were furtherly selected for the final analysis; the appearance of necrosis was assessed at histopathologic examination and MRI. Irradiated melanomas showed a higher degree of necrosis as compared with nonirradiated tumors. Irradiated and nonirradiated lesions differed based on the appearance and distribution of necrosis. Irradiated tumors showed large necrotic foci, sharply demarcated from the viable neoplastic tissue; nonirradiated tumors demonstrated small, distinct foci of necrosis. Radiation-induced necrosis, more pigmented than surrounding viable tumor, displayed high signal intensity on T1-weighted and low signal intensity on T2-weighted images. The hemorrhagic/coagulative necrosis, more prevalent in nonirradiated tumors (4 out of 6 vs. 1 out of 7 cases), appeared hyperintense on T2-weighted and hypointense on T1-weighted images. Our study boosts the capability to recognize radiation-induced alterations in uveal melanomas at MRI and may improve the accuracy of radiologists in the evaluation of follow-up MR examination after radiotherapy.
葡萄膜黑色素瘤中的坏死可以是自发的，也可以由放射治疗诱发。我们研究的目的是比较一组接受质子束照射的葡萄膜黑色素瘤的放射诱导坏死与一组接受原发眼球摘除术的对照组患者的自发坏死的组织病理学和MRI表现。回顾性确定了11例接受质子束放疗、MRI检查及二期眼球摘除术的葡萄膜黑色素瘤患者，以及15例接受MRI检查及原发眼球摘除术的未经治疗的葡萄膜黑色素瘤患者作为对照组。在照射组和未照射组中，分别进一步选择7只和6只具有坏死组织学证据的眼睛进行最终分析；在组织病理学检查和MRI上评估坏死的表现。与未照射的肿瘤相比，照射后的黑色素瘤坏死程度更高。照射和未照射的病变在坏死的外观和分布上有所不同。照射后的肿瘤显示出大的坏死灶，与存活的肿瘤组织界限清晰；未照射的肿瘤表现为小的、离散的坏死灶。放射诱导的坏死比周围存活的肿瘤色素沉着更多，在T1加权像上呈高信号强度，在T2加权像上呈低信号强度。出血性/凝固性坏死在未照射的肿瘤中更常见（6例中有4例，而7例中有1例），在T2加权像上呈高信号，在T1加权像上呈低信号。我们的研究提高了在MRI上识别葡萄膜黑色素瘤放射诱导改变的能力，并可能提高放射科医生在放疗后随访MR检查评估中的准确性。
