Carcinoma of an Unknown Primary Site
http://www.100md.com
《新英格兰医药杂志》
Carcinoma of an unknown primary site (CUP) is a common and often puzzling condition. It is probably underdiagnosed because clinicians may be reluctant to acknowledge the uncertainty of such a diagnosis (a "best guess" diagnosis may be applied). Yet CUP is a specific entity that demands clinical problem solving once the histopathology and distribution of the metastases have been established. Patients with visceral or skeletal metastases are expected to survive only a few months, whereas patients with only lymph node metastases may survive for many years.
The definition of CUP is metastatic carcinoma detected when the primary site of origin is not indicated by a thorough history, a complete physical examination, routine laboratory tests, chest radiography, and careful review of the biopsy specimen with the pathologist. Physicians frequently embark on a laborious and expensive diagnostic pursuit in a vain search for a primary site. The futility rather than the utility of such an effort should be stressed: despite an exhaustive search, the primary site remains elusive in about 80% of patients. Furthermore, identifying the primary site usually has little effect on the prognosis.
Fizazi has nicely organized a complete review and analysis of the topic. He and his coauthors present the selection and limitations of diagnostic tests in a thorough and rational manner (although with a bit more optimism for success than this reviewer has). Voigt and colleagues recommend the pragmatic use of a limited number of immunohistochemical tests for pathologic diagnosis. I was also impressed with the conclusion that positron-emission tomography has limited usefulness in the CUP syndrome, particularly given the current popularity of this expensive test.
Why should a prostate cancer that presents as CUP have a different metastatic pattern from a prostate cancer that presents as recognizable prostate cancer? This book offers an erudite discussion of what is known about the unique biology of the strange behavior of cancers of unknown origin.
The authors emphasize that there are patients with CUP who are treatable, with a high expectancy of a favorable result. They include patients with metastases only to single lymph-node regions, men with lymph-node metastases in a midline distribution, women with possible breast cancer or peritoneal carcinomatosis, and patients with poorly differentiated neuroendocrine carcinomas. For such patients with disseminated metastases, the use of modern chemotherapy combinations is presented in a fair light.
Fizazi also includes a chapter on quality-of-life and psychosocial issues. He recognizes the unique psychological effect when a patient is told that his or her cancer has metastasized, that we do not know where it came from, and that it probably would not make any difference if we did know. This complex matter is difficult for the patient, the patient's family, and perhaps caregivers to understand fully.
Dennis A. Casciato, M.D.
UCLA School of Medicine
West Los Angeles, CA 90095(Edited by Karim Fizazi. 2)
The definition of CUP is metastatic carcinoma detected when the primary site of origin is not indicated by a thorough history, a complete physical examination, routine laboratory tests, chest radiography, and careful review of the biopsy specimen with the pathologist. Physicians frequently embark on a laborious and expensive diagnostic pursuit in a vain search for a primary site. The futility rather than the utility of such an effort should be stressed: despite an exhaustive search, the primary site remains elusive in about 80% of patients. Furthermore, identifying the primary site usually has little effect on the prognosis.
Fizazi has nicely organized a complete review and analysis of the topic. He and his coauthors present the selection and limitations of diagnostic tests in a thorough and rational manner (although with a bit more optimism for success than this reviewer has). Voigt and colleagues recommend the pragmatic use of a limited number of immunohistochemical tests for pathologic diagnosis. I was also impressed with the conclusion that positron-emission tomography has limited usefulness in the CUP syndrome, particularly given the current popularity of this expensive test.
Why should a prostate cancer that presents as CUP have a different metastatic pattern from a prostate cancer that presents as recognizable prostate cancer? This book offers an erudite discussion of what is known about the unique biology of the strange behavior of cancers of unknown origin.
The authors emphasize that there are patients with CUP who are treatable, with a high expectancy of a favorable result. They include patients with metastases only to single lymph-node regions, men with lymph-node metastases in a midline distribution, women with possible breast cancer or peritoneal carcinomatosis, and patients with poorly differentiated neuroendocrine carcinomas. For such patients with disseminated metastases, the use of modern chemotherapy combinations is presented in a fair light.
Fizazi also includes a chapter on quality-of-life and psychosocial issues. He recognizes the unique psychological effect when a patient is told that his or her cancer has metastasized, that we do not know where it came from, and that it probably would not make any difference if we did know. This complex matter is difficult for the patient, the patient's family, and perhaps caregivers to understand fully.
Dennis A. Casciato, M.D.
UCLA School of Medicine
West Los Angeles, CA 90095(Edited by Karim Fizazi. 2)