LV Prasad Eye Institute, MTC Campus, Bhubaneswar, Odisha, India.
Fondation Asile des Aveugles, Jules-Gonin Eye Hospital, University of Lausanne, Lausanne, Switzerland.
BMC Ophthalmol. 2024 Jan 30;24(1):47. doi: 10.1186/s12886-024-03307-x.
Retinoblastoma (rb) is the most frequent intraocular tumor, accounting for 3% of all childhood cancers. Heritable rb survivors are germline carriers for an RB1 mutation and have a lifelong risk to develop non-ocular second primary tumors (SPTs) involving multiple other organs like the bones, soft tissues, or skin. These SPTs usually become manifest several years succeeding the diagnosis of rb. In our instance, however, a non-ocular SPT presented prior to the diagnosis of heritable rb.
We report a rare case of a monozygotic twin who presented with primary rhabdomyosarcoma (RMS) preceding the manifestation of heritable rb. The rb was diagnosed when the child developed strabismus while already on therapy for the RMS. The child underwent therapy for both as per defined treatment protocols. The rb regressed well on treatment, but the RMS relapsed and the child developed multiple refractory metastatic foci and succumbed to his disease.
Non-ocular SPTs like sarcomas are usually known to manifest in heritable rb survivors with a lag of two to three decades (earlier if exposure to radiation is present) from the presentation of the rb. However, in our case, this seemed to be reversed with the RMS being manifest at an unusual early age and the rb being diagnosed at a later point in time.
视网膜母细胞瘤（rb）是最常见的眼内肿瘤，占所有儿童癌症的 3%。遗传性 rb 幸存者是 RB1 突变的种系携带者，终生有发展非眼部第二原发肿瘤（SPT）的风险，涉及多个其他器官，如骨骼、软组织或皮肤。这些 SPT 通常在 rb 诊断后数年表现出来。然而，在我们的病例中，一种非眼部 SPT 在遗传性 rb 之前表现出来。
我们报告了一例罕见的单卵双胞胎病例，该双胞胎在遗传性 rb 表现之前出现原发性横纹肌肉瘤（RMS）。当孩子在 RMS 治疗期间出现斜视时，rb 被诊断出来。孩子按照既定的治疗方案接受了两种疾病的治疗。rb 在治疗后消退良好，但 RMS 复发，孩子出现多个难治性转移性病灶，并死于疾病。
非眼部 SPT 如肉瘤通常在遗传性 rb 幸存者中表现出来，从 rb 出现到肉瘤出现有 2 到 3 十年的潜伏期（如果存在辐射暴露则更早）。然而，在我们的病例中，这种情况似乎被逆转了，RMS 以不寻常的早龄表现出来，而 rb 则在稍后的时间被诊断出来。
