tailieunhanh - Chapter 095. Carcinoma of Unknown Primary

Carcinoma of unknown primary (CUP) is a biopsy-proven (mainly epithelial) malignancy for which the anatomic site of origin remains unidentified after an intensive search. CUP is one of the 10 most frequently diagnosed cancers worldwide, accounting for approximately 3–5% of all cancer cases. Most investigators do not consider lymphomas, metastatic melanomas, and metastatic sarcomas that present without a known primary tumor to be CUP because these cancers have specific stage- and histology-based treatments that can guide management. . | Chapter 095. Carcinoma of Unknown Primary Carcinoma of unknown primary CUP is a biopsy-proven mainly epithelial malignancy for which the anatomic site of origin remains unidentified after an intensive search. CUP is one of the 10 most frequently diagnosed cancers worldwide accounting for approximately 3-5 of all cancer cases. Most investigators do not consider lymphomas metastatic melanomas and metastatic sarcomas that present without a known primary tumor to be CUP because these cancers have specific stage- and histology-based treatments that can guide management. A standard workup for CUP includes a medical history physical examination and laboratory studies including liver and renal function tests hemogram chest x-ray CT scan of the abdomen and pelvis mammography in women and prostatespecific antigen PSA test in men. With the increasing availability of additional sophisticated imaging techniques and the emergence of targeted therapies that have been shown to be effective in several cancers oncologists must decide on the extent of workup that is warranted. Specifically they must consider how additional diagnostic procedures may affect the choice of therapy and the patient s survival and quality of life. The reason tumors present as CUP remains unclear. One hypothesis is that the primary tumor either regresses after seeding the metastasis or remains so small that it is not detected. It is possible that CUP falls on the continuum of cancer presentation where the primary has been contained or eliminated by the natural body defenses. Alternatively CUP may represent a specific malignant event that results in an increase in metastatic spread or survival relative to the primary. Whether the CUP metastases truly define a clone that is genetically and phenotypically unique to this diagnosis remains to be determined. Introduction No characteristics that are unique to CUP relative to metastases from known primaries have been identified. Abnormalities in chromosomes 1 and 12