Metastasis to the breast from colorectal carcinoma is rare, only a few cases have been reported in the literature, and no cases have been reported in a young, 28-year-old patient. This report confirms the occurrence of the disease in a younger age group. The patient was referred to the Breast Clinic with a history of a gradually increasing lump in her right breast for two weeks' duration. On clinical examination, a 2-cm firm lump was noted in the upper inner quadrant of the right breast, which was clinically benign; however, histological examination of the breast core biopsy together with immunohistochemistry confirmed metastatic colorectal adenocarcinoma. The primary colorectal carcinoma was later confirmed to be a stage pT4N2M1 tumor, and the Duke stage was C1. Histology with immunohistochemistry is very important in the diagnosis of cases of this nature, but the clinical correlation should be taken into consideration at multidisciplinary team meetings to decide the final management of the patient.
Adenocarcinoma* ; Adult* ; Biopsy ; Breast* ; Colon ; Colon, Sigmoid* ; Colorectal Neoplasms ; Diagnosis ; Female* ; Humans ; Immunohistochemistry ; Neoplasm Metastasis*

The POLG gene encodes mitochondrial DNA polymerase, and mutations in this gene cause a spectrum of disorders related to mitochondrial DNA depletion or deletion. Dystonia has only rarely been reported as an early and prominent manifestation of POLG mutations. We report a case of a 30-year-old male presenting with lower limb dystonia with peripheral neuropathy and demonstrate that the dystonia was levodopa responsive (with video findings). Whole-genome sequencing revealed biallelic variants in the POLG gene: a known pathogenic variant [NM_001126131.2:c.2209G>C (p.Gly737Arg)] and a novel likely pathogenic variant [NM_001126131.2:c.3305A>C (p.Gln1102Pro)]. A genetic diagnosis was made before the appearance of more readily recognizable features of mitochondrial disease, allowing us to avoid invasive tissue biopsies or potentially deleterious treatments, such as sodium valproate. A POLG-related disorder should be suspected in cases of dystonia with peripheral neuropathy, and this diagnosis may have implications for further investigations and management.

The POLG gene encodes mitochondrial DNA polymerase, and mutations in this gene cause a spectrum of disorders related to mitochondrial DNA depletion or deletion. Dystonia has only rarely been reported as an early and prominent manifestation of POLG mutations. We report a case of a 30-year-old male presenting with lower limb dystonia with peripheral neuropathy and demonstrate that the dystonia was levodopa responsive (with video findings). Whole-genome sequencing revealed biallelic variants in the POLG gene: a known pathogenic variant [NM_001126131.2:c.2209G>C (p.Gly737Arg)] and a novel likely pathogenic variant [NM_001126131.2:c.3305A>C (p.Gln1102Pro)]. A genetic diagnosis was made before the appearance of more readily recognizable features of mitochondrial disease, allowing us to avoid invasive tissue biopsies or potentially deleterious treatments, such as sodium valproate. A POLG-related disorder should be suspected in cases of dystonia with peripheral neuropathy, and this diagnosis may have implications for further investigations and management.