Unmasking neurofibromatosis type 1 with the discovery of a renal neurofibroma
- 1Universidad Nacional del Nordeste, Facultad de Medicina, Mariano Moreno 1240, Ciudad de Corrientes, W3400, Argentina; Laboratorio de Aplicaciones en inmunohistoquímica, Facultad de Medicina, Universidad Nacional del Nordeste, Juan Bautista Cabral 2001, Ciudad de Corrientes, W3400, Argentina
Abstract
Background: Neurofibromatosis type 1 (NF1) predisposes patients to various tumors. However, the sequential occurrence of rare visceral neoplasms of different histological origins in a single patient is exceptional. Case presentation: A two-year-old male was diagnosed with an embryonal bladder rhabdomyosarcoma (RMS). A decade later, at age 12, he presented with lumbar pain; subsequent imaging revealed a suspicious renal mass, prompting a nephrectomy. Histopathological and immunohistochemical analyses confirmed a plexiform renal neurofibroma (RNF). This unexpected RNF discovery prompted a comprehensive clinical evaluation, revealing skeletal dysplasia and café-au-lait macules; molecular genetic testing subsequently identified a de novo pathogenic NF1 variant, establishing the diagnosis. Conclusion: This constitutes, an extremely rare documented case of an RNF associated with NF1. It underscores that any visceral neurofibroma mandates ruling out underlying syndromic conditions. Crucially, it underscores the rare occurrence of a renal neurofibroma as a second, histologically distinct neoplasm in a pediatric NF1 patient who is a long-term survivor of bladder RMS, and highlights the value of extended oncologic surveillance, bearing in mind that the cardinal cutaneous, neural, and skeletal stigmata of NF1 emerge at different ages and need not all be present in early childhood.
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BibTeX
@article{rodriguez2026unmasking,
title = {{Unmasking neurofibromatosis type 1 with the discovery of a renal neurofibroma}},
author = {Exequiel Alberto Rodríguez and María Agustina Sivori Delvaux and Jessika Susana Aymara Navarro Lopez and Bertha Mercedes Valdovinos Zaputovich},
journal = {Pediatric Hematology Oncology Journal},
year = {2026},
month = oct,
doi = {10.1016/j.phoj.2026.101168},
url = {https://doi.org/10.1016/j.phoj.2026.101168},
note = {CC BY},
}
RIS
TY - JOUR
TI - Unmasking neurofibromatosis type 1 with the discovery of a renal neurofibroma
AU - Exequiel Alberto Rodríguez
AU - María Agustina Sivori Delvaux
AU - Jessika Susana Aymara Navarro Lopez
AU - Bertha Mercedes Valdovinos Zaputovich
PY - 2026
DA - 2026/10/30
JO - Pediatric Hematology Oncology Journal
DO - 10.1016/j.phoj.2026.101168
UR - https://doi.org/10.1016/j.phoj.2026.101168
AB - Background: Neurofibromatosis type 1 (NF1) predisposes patients to various tumors. However, the sequential occurrence of rare visceral neoplasms of different histological origins in a single patient is exceptional. Case presentation: A two-year-old male was diagnosed with an embryonal bladder rhabdomyosarcoma (RMS). A decade later, at age 12, he presented with lumbar pain; subsequent imaging revealed a suspicious renal mass, prompting a nephrectomy. Histopathological and immunohistochemical analyses confirmed a plexiform renal neurofibroma (RNF). This unexpected RNF discovery prompted a comprehensive clinical evaluation, revealing skeletal dysplasia and café-au-lait macules; molecular genetic testing subsequently identified a de novo pathogenic NF1 variant, establishing the diagnosis. Conclusion: This constitutes, an extremely rare documented case of an RNF associated with NF1. It underscores that any visceral neurofibroma mandates ruling out underlying syndromic conditions. Crucially, it underscores the rare occurrence of a renal neurofibroma as a second, histologically distinct neoplasm in a pediatric NF1 patient who is a long-term survivor of bladder RMS, and highlights the value of extended oncologic surveillance, bearing in mind that the cardinal cutaneous, neural, and skeletal stigmata of NF1 emerge at different ages and need not all be present in early childhood.
SN - 2468-1245
ER -