ABS CGSO key terms

A scheduled meeting where surgeons, medical and radiation oncologists, radiologists, pathologists, and allied staff review a patient's case together and agree on a recommended treatment plan.

A written, coordinated plan that sets out the agreed diagnostic steps, treatments, timelines, and responsible clinicians for a patient, produced jointly by the treating team and the patient.

A process in which the clinician explains options, benefits, and harms, and the patient's values and preferences are weighed together to choose a course of care.

A patient's voluntary agreement to a test or treatment after receiving and understanding information about its purpose, expected benefits, risks, alternatives, and the consequences of declining.

Treatment, usually chemotherapy, radiotherapy, or both, given before planned definitive surgery or radiotherapy to shrink a tumor and improve the chance of complete removal.

Additional treatment given after the primary curative treatment, such as surgery, to destroy residual microscopic disease and reduce the risk of recurrence.

The systematic assessment of how far a cancer has spread, using tumor size, lymph node involvement, and distant metastases, to guide treatment choice and estimate prognosis.

A staging system that describes the primary tumor (T), regional lymph node involvement (N), and distant spread (M), which are combined to assign an overall stage.

The spread of cancer cells from the original tumor to distant organs or lymph nodes, where they grow into secondary tumors.

Microscopic examination of tissue samples by a pathologist to confirm whether cells are malignant, identify the tumor type and grade, and assess margins and other features.

Removal of a small sample of tissue or cells for laboratory examination, used to confirm a cancer diagnosis and determine its type.

A minimally invasive sampling technique in which a thin needle withdraws cells from a lump or mass for cytological examination, often used for accessible lesions such as neck or breast masses.

A description of how closely cancer cells resemble normal cells and how rapidly they appear to divide, usually reported on a scale from low to high grade.

The degree to which cancer cells retain features of the normal tissue they arose from; poorly differentiated tumors look less like normal tissue and often behave more aggressively.

A laboratory technique using antibodies that bind specific proteins in tissue, producing a colored signal that helps identify tumor type, origin, and predictive markers.

A measurable biological characteristic, such as a protein, gene alteration, or blood molecule, that indicates disease presence, prognosis, or likely response to a particular therapy.

A biomarker that indicates how likely a tumor is to respond to a specific treatment, such as a receptor status guiding targeted therapy choice.

Testing a blood or other body fluid sample for tumor-derived material such as circulating tumor DNA, used to detect, monitor, or characterize cancer without sampling the tumor itself.

Fragments of DNA released into the bloodstream by cancer cells, which can be measured to monitor tumor burden or detect resistance mutations.

A cancer confirmed by biopsy whose original site cannot be identified after a structured diagnostic workup, requiring tissue-based profiling to guide empiric or targeted treatment.

Symptoms or signs caused by substances released by a tumor or by the body's immune response to it, occurring at a site distant from the tumor itself.

A diverse group of rare cancers that arise from connective tissues such as bone, fat, muscle, or blood vessels, often requiring specialist multidisciplinary management.

A rare tumor arising from hormone-producing cells, often slow-growing, which can secrete substances causing distinctive hormonal syndromes and may require specialized imaging and treatment.

Reduction in the extent of a tumor after preoperative treatment, so that it is classified at a lower stage than before therapy, sometimes enabling surgery that was initially not feasible.

The estimated probability that cancer will return after treatment, based on tumor stage, grade, biology, and treatment received, and used to decide whether adjuvant therapy is worthwhile.

Scheduled follow-up visits and tests after treatment aimed at detecting recurrence, new cancers, or late effects early, with intervals tailored to the cancer type and risk.

Drugs designed to act on specific molecules or pathways that drive a particular cancer's growth, usually chosen after testing the tumor for the relevant marker.

Treatment that helps the patient's immune system recognize and attack cancer cells, for example by blocking proteins that restrain immune responses.

Inflammatory side effects caused by immunotherapy when the activated immune system attacks normal organs, such as the bowel, lungs, thyroid, or skin, requiring prompt recognition and treatment.

Coordinated services that help a person with cancer maintain or restore physical function, manage symptoms, and participate in work and daily life before, during, and after treatment.

Assessment and intervention before cancer treatment, such as exercise, nutrition support, and smoking cessation, to improve fitness and reduce complications and functional decline.

A persistent, distressing sense of tiredness related to cancer or its treatment that is not proportional to recent activity and interferes with usual functioning.

Swelling of a limb or body region caused by accumulation of lymph fluid after lymph nodes or lymph channels are damaged by surgery or radiotherapy.

Surgical removal of some or all regional lymph nodes, done to stage cancer or remove involved nodes, and associated with risks such as lymphedema and nerve injury.

Organized testing of people without symptoms in a defined population to find cancer or precancerous lesions early, with defined eligibility, follow-up, and quality standards.

Detection of a cancer through screening that would never have caused symptoms or harm during the person's lifetime, leading to unnecessary treatment.

An abnormal tissue change that is not itself invasive cancer but carries an increased chance of progressing to cancer if left untreated.

Actions that reduce the chance of cancer developing at all, such as avoiding tobacco, maintaining a healthy weight, vaccination, and limiting sun exposure.

Vaccination against human papillomavirus, given before exposure to prevent infections that can lead to cervical and other cancers.

A prospective research study that assigns participants to interventions and measures outcomes to answer questions about safety, efficacy, or quality of cancer care.

The assignment of trial participants to treatment groups by chance, which reduces bias and makes groups comparable so that differences in outcomes can be attributed to the intervention.