Phenotypes associated with the disease mismatch repair cancer syndrome 1 (OMIM:276300):
- Adenomatous colonic polyposis (HP:0005227): Presence of multiple adenomatous polyps in the colon. Evidence: PCS. Frequency: 9/18. (PMID:24440087)
- Basal cell carcinoma (HP:0002671): The presence of a basal cell carcinoma of the skin. Evidence: IEA. (OMIM:276300)
- Agenesis of corpus callosum (HP:0001274): Absence of the corpus callosum as a result of the failure of the corpus callosum to develop, which can be the result of a failure in any one of the multiple steps of callosal development including cellular proliferation and migration, axonal growth or glial patterning at the midline. Evidence: PCS. Frequency: 2/3. (PMID:22692065)
- Hypopigmentation of the skin (HP:0001010): A reduction of skin color related to a decrease in melanin production and deposition. Evidence: PCS. Frequency: 3/18. (PMID:24440087)
- Gray matter heterotopia (HP:0002282): Heterotopia or neuronal heterotopia are macroscopic clusters of misplaced neurons (gray matter), most often situated along the ventricular walls or within the subcortical white matter. Evidence: PCS. Frequency: 2/3. (PMID:22692065)
- Non-Hodgkin lymphoma (HP:0012539): A type of lymphoma characterized microscopically by the absence of multinucleated Reed-Sternberg cells. Evidence: PCS. Frequency: 1/3. (PMID:22692065)
- Leukemia (HP:0001909): A cancer of the blood and bone marrow characterized by an abnormal proliferation of leukocytes. Evidence: PCS. Frequency: 1/18. (PMID:24440087)
- Astrocytoma (HP:0009592): Astrocytoma is a neoplasm of the central nervous system derived from astrocytes. Astrocytes are a type of glial cell, and thus astrocytoma is a subtype of glioma. Evidence: PCS. Frequency: 11/13. (PMID:24440087;PMID:22692065)
- Pleomorphic xanthoastrocytoma (HP:0033682): Pleomorphic xanthoastrocytomas (PXA) are rare low-grade astrocytomas (WHO Grade II) typically found in the temporal lobe and classically presenting with epilepsy. PXA is an astrocytic neoplasm that most often presents in children or young adults but can also occur in adults. The diagnosis of anaplastic PXA is made based upon tumor histopathologic characteristics and requires increased proliferative activity (mitotic index at least 5 mitoses/10 HPF), which is associated with worse overall survival. In general, anaplastic PXAs acquire features of a more aggressive astrocytic neoplasm that can include increased proliferation, necrosis, microvascular proliferation, loss of pericellular reticulin, and increased infiltrative growth. Evidence: PCS. Frequency: 1/18. (PMID:24440087)
- Adenocarcinoma of the small intestine (HP:0040274): A malignant epithelial tumor with a glandular organization that originates in the small intestine. Evidence: PCS. Frequency: 2/18. (PMID:24440087)
- Oligodendroglioma (HP:0033681): Oligodendroglioma is a type of diffusely infiltrating glioma and constitutes approximately 5% of primary intracranial tumors. They often involve the cortical gray matter and are most commonly seen in the frontal lobes. OGs are generally low grade WHO grade II neoplasms that are slow-growing tumors and have a favorable treatment response when compared to other gliomas. Grade III anaplastic OG is a more malignant form of the tumor which portends a less favorable prognosis and may occur de novo or as degeneration from the lower grade OG. Evidence: PCS. Frequency: 2/18. (PMID:24440087)
- Glioblastoma multiforme (HP:0012174): A tumor arising from glia in the central nervous system with macroscopic regions of necrosis and hemorrhage. Microscopically, glioblastoma multiforme is characterized by regions of pseudopalisading necrosis, pleomorphic nuclei and cells, and microvascular proliferation. Evidence: PCS. Frequency: 10/21. (PMID:24440087;PMID:22692065)
- Adenocarcinoma of the colon (HP:0040276). Evidence: PCS. Frequency: 1/18. (PMID:24440087)
- T-cell lymphoma (HP:0012190): A type of lymphoma that originates in T-cells. Evidence: PCS. Frequency: 2/3. (PMID:22692065)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:22692065)
- Axillary freckling (HP:0000997): The presence in the axillary region (armpit) of an increased number of freckles, small circular spots on the skin that are darker than the surrounding skin because of deposits of melanin. Evidence: PCS. Frequency: 3/18. (PMID:24440087)
- Rhabdomyosarcoma (HP:0002859). Evidence: IEA. (OMIM:276300)
- Multiple cafe-au-lait spots (HP:0007565): The presence of six or more cafe-au-lait spots. Evidence: PCS. Frequency: 20/21. (PMID:24440087;PMID:22692065)
- Plexiform neurofibroma (HP:0009732): A neurofibroma in which Schwann cells proliferate inside the nerve sheath, producing an irregularly thickened, distorted, tortuous structure. Evidence: PCS. Frequency: 1/18. (PMID:24440087)
- Ependymoma (HP:0002888): The presence of an ependymoma of the central nervous system. Evidence: IEA. (OMIM:276300)
- Lymphoma (HP:0002665): A cancer originating in lymphocytes and presenting as a solid tumor of lymhpoid cells. Evidence: PCS. Frequency: 5/18. (PMID:24440087)
- Medulloblastoma (HP:0002885): A rapidly growing embryonic tumor arising in the posterior part of the cerebellar vermis and neuroepithelial roof of the fourth ventricle in children. More rarely, medulloblastoma arises in the cerebellum in adults. Evidence: PCS. (PMID:24440087)
- Neuroblastoma (HP:0003006): Neuroblastoma is a solid tumor that originate in neural crest cells of the sympathetic nervous system. Most neuroblastomas originate in the abdomen, and most abdominal neuroblastomas originate in the adrenal gland. Neuroblastomas can also originate in the thorax, usually in the posterior mediastinum. Evidence: IEA. (OMIM:276300)