Point-of-care, easy to manufacture, and low cost detection of cancer biomarkers is crucial for fighting the early stage disease. 3D printing allows delocalized printing at remote locations with updates/upgrades available globally via electronic files. Mucin 1 (MUC1) is a protein that is overexpressed in a number of epithelial cancers and is a key factor in advancement of the disease. Here we show the simple point-of-care 3D printing fabrication of a MUC1 aptasensor using a nanocarbon/polymer filament. Efficacy of the 3D-printed aptasensor is demonstrated by monitoring the expression and release of MUC1 in breast cancer cell cultures. Such a simple, low cost, and easy to locally fabricate cancer biosensor will have a large impact on the field of cancer diagnostics.