CUP stands for **cancer of unknown primary**. It means cancer is found in the body, but the place where it started (the **primary site**) is not identified after a standard evaluation. CUP is most often diagnosed when cancer is discovered as **metastatic disease** (spread to lymph nodes or other organs). The term is commonly used by oncology teams in pathology reports, imaging summaries, and treatment planning.

Cancer of unknown primary is a cancer diagnosis used when metastatic cancer is found, but the original starting site (the “primary” tumor) cannot be identified. It usually means cancer has been detected in one or more organs or lymph nodes away from where it began. It is commonly used in oncology, pathology, radiology, and multidisciplinary cancer care planning. It describes a clinical situation rather than a single specific cancer type.

Multiple primary cancer means a person has more than one distinct cancer, each starting in a different place or from a different cell type. It is different from cancer that has spread (metastasized) or come back (recurrence). The term is used in oncology clinics, pathology reports, tumor boards, and cancer registries. It helps clinicians describe, stage, and plan care when more than one cancer diagnosis is present.

Chondrosarcoma is a cancer that forms cartilage-like tissue. It most often develops in bones such as the pelvis, femur, or shoulder region. It is commonly discussed and treated in sarcoma programs within orthopedic and cancer centers. It is used as a clinical diagnosis to guide imaging, biopsy, staging, and treatment planning.

Ewing sarcoma is a rare cancer that most often starts in bone, but it can also begin in soft tissues. It belongs to a group of cancers called sarcomas, which develop from connective tissues such as bone, muscle, or fibrous tissue. It is commonly discussed in pediatric and adolescent/young adult oncology because it occurs more often in younger people, though adults can be affected. In clinical care, the term Ewing sarcoma is used to describe a specific tumor type with characteristic pathology and genetic features.

Osteosarcoma is a cancer that starts in bone-forming cells and produces abnormal bone tissue. It most often develops in the long bones, such as around the knee, upper arm, or hip. It is commonly discussed in orthopedic oncology, pediatric oncology, and sarcoma care. It is treated as a medical emergency in oncology because it can grow quickly and spread.

Bone sarcoma is a rare group of cancers that start in bone or the tissue around bone. It is different from cancers that spread to bone from another organ (bone metastases). The term is commonly used in orthopedic oncology, medical oncology, radiation oncology, and pathology. It is also used in imaging and biopsy reports when a primary bone tumor is suspected or confirmed.

Angiosarcoma is a rare cancer that develops from cells lining blood vessels or lymph vessels. It is a type of soft tissue sarcoma, meaning a cancer of connective and supportive tissues. It can occur in the skin, breast, liver, heart, and deeper soft tissues. The term Angiosarcoma is used in oncology, pathology, and radiology to describe this specific vascular cancer diagnosis.

Synovial sarcoma is a rare type of soft tissue sarcoma, which is a cancer that starts in connective tissues like muscle, fat, or fibrous tissue. Despite its name, it usually does not arise from the synovium (the lining of joints). It most often develops near joints in an arm or leg, but it can occur in many body locations. In cancer care, the term is used to describe a specific sarcoma diagnosis confirmed by pathology and molecular testing.

Leiomyosarcoma is a rare type of cancer that starts in smooth muscle cells. Smooth muscle is the involuntary muscle found in places like the uterus, blood vessels, and the digestive tract. Leiomyosarcoma is most often discussed in cancer care when evaluating a mass (tumor) in soft tissues or organs. It is commonly managed by multidisciplinary sarcoma teams that include surgery, medical oncology, and radiation oncology.