C81-C96: Malignant neoplasms, stated or presumed to be primary, of lymphoid, haematopoietic and related tissue

C85: Other and unspecified types of non-Hodgkin lymphoma

Non-Hodgkin lymphoma (NHL) is a group of cancers that start in white blood cells called lymphocytes, integral to the body's immune system. The category C85 refers to a diverse set of NHL subtypes that may not fit into a specific type or are unspecified. These lymphomas can be either less aggressive (indolent) or more aggressive, with faster progression. Non-Hodgkin lymphoma can occur anywhere in the body, generally presenting as swollen lymph nodes, fever, fatigue, or unexplained weight loss. Its exact cause remains unknown, but risk factors include a weakened immune system, certain infections, and age over 60. The illness can affect multiple aspects of the body's functioning depending on the tumor's location and extent of spread. It's important to note that the exact symptoms and progression can vary widely due to the diversity within this group of lymphomas.