Colon cancer in a patient with a mosaic monoallelic germline pathogenic NF1 gene variant.
6 affiliations
- 1CLS Health Comprehensive Care Clinic-Clear Lake, Webster, TX 77598, USA.
- 2Department of Clinical Genomics, Mayo Clinic, Phoenix, AZ 85054, USA.
- 3Department of Health Sciences Research, Mayo Clinic Arizona, Scottsdale, AZ 85259, USA.
- 4Department of Neurology, Mayo Clinic, Phoenix, AZ 85054, USA.
- 5Department of Clinical Genomics, Mayo Clinic, Rochester, MN 55905, USA.
- 6Division of Medical Oncology, Mayo Clinic Cancer Center, Mayo Clinic, Phoenix, AZ 85054, USA.
Abstract
Pathogenic variants in the tumor suppressor gene NF1 cause neurofibromatosis type 1 (NF1), one of the most common hereditary cancer predisposition syndromes. Pathogenic NF1 variants have been associated with an increased risk of several cancers; however, the relationship between NF1 variation and colon cancer remains underreported. We report a 41-year-old woman with a mosaic monoallelic germline pathogenic NF1 variant, NM_000267.3:c.1756_1759del (p.Thr586Valfs*18), previously detected on germline multigene panel testing in saliva at a variant allele frequency of approximately 35%. She later presented with fatigue, dyspnea on exertion, and iron-deficiency anemia. Computed tomography, colonoscopy, biopsy, mismatch repair immunohistochemistry, surgical pathology, and tumor next-generation sequencing led to the diagnosis of right-sided colon adenocarcinoma that was mismatch repair deficient (dMMR) and microsatellite instability-high (MSI-H). She underwent right hemicolectomy, recovered postoperatively, and entered standard surveillance; at the time of manuscript development, she was also receiving systemic therapy. This case highlights the co-occurrence of an NF1 variant and dMMR colorectal cancer and underscores the need for further studies to determine whether this represents a coincidental finding or a biologically meaningful association.
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BibTeX
@article{alsabagh2026colon,
title = {{Colon cancer in a patient with a mosaic monoallelic germline pathogenic NF1 gene variant.}},
author = {Feras Alsabagh and Karam M Chaaban and Marlene Girardo and Ehab Harahsheh and Misha B Asif and Dusica Babovic-Vuksanovic and Mohamad Bassam Sonbol and Mayowa A Osundiji},
journal = {Exploration of neuroscience},
year = {2026},
month = sep,
doi = {10.37349/en.2026.1006148},
url = {https://europepmc.org/article/MED/42852273},
note = {CC BY},
}
RIS
TY - JOUR
TI - Colon cancer in a patient with a mosaic monoallelic germline pathogenic NF1 gene variant.
AU - Feras Alsabagh
AU - Karam M Chaaban
AU - Marlene Girardo
AU - Ehab Harahsheh
AU - Misha B Asif
AU - Dusica Babovic-Vuksanovic
AU - Mohamad Bassam Sonbol
AU - Mayowa A Osundiji
PY - 2026
DA - 2026/09/03
JO - Exploration of neuroscience
DO - 10.37349/en.2026.1006148
UR - https://europepmc.org/article/MED/42852273
AB - Pathogenic variants in the tumor suppressor gene NF1 cause neurofibromatosis type 1 (NF1), one of the most common hereditary cancer predisposition syndromes. Pathogenic NF1 variants have been associated with an increased risk of several cancers; however, the relationship between NF1 variation and colon cancer remains underreported. We report a 41-year-old woman with a mosaic monoallelic germline pathogenic NF1 variant, NM_000267.3:c.1756_1759del (p.Thr586Valfs*18), previously detected on germline multigene panel testing in saliva at a variant allele frequency of approximately 35%. She later presented with fatigue, dyspnea on exertion, and iron-deficiency anemia. Computed tomography, colonoscopy, biopsy, mismatch repair immunohistochemistry, surgical pathology, and tumor next-generation sequencing led to the diagnosis of right-sided colon adenocarcinoma that was mismatch repair deficient (dMMR) and microsatellite instability-high (MSI-H). She underwent right hemicolectomy, recovered postoperatively, and entered standard surveillance; at the time of manuscript development, she was also receiving systemic therapy. This case highlights the co-occurrence of an NF1 variant and dMMR colorectal cancer and underscores the need for further studies to determine whether this represents a coincidental finding or a biologically meaningful association.
SN - 2834-5347
ER -