Adenocarcinoma of unknown primary site
Summary
Definition
History and exam
Key diagnostic factors
- bone pain
- FHx of cancer
Other diagnostic factors
- jaundice
- ascites
- personal hx of previous cancer
- hx of smoking
- pain
- palpable mass
- symptoms of postobstructive pneumonia
- neurologic pain or weakness
- headaches
- seizures
- cervical chain adenopathy
- constitutional symptoms
- depression
- delirium
- hx of heavy alcohol consumption
- hepatomegaly
- hemoptysis
Risk factors
- age >60 years
- black ancestry
Diagnostic investigations
1st investigations to order
- CXR
- CT (chest, abdomen, pelvis)
- mammography
- MRI of breast
- transvaginal ultrasound
- diagnostic paracentesis
- upper aerodigestive panendoscopy (for patients with isolated cervical adenopathy)
Investigations to consider
- colonoscopy (for patients with resectable liver metastases)
- light microscopy, with hematoxylin and eosin (H&E) staining
- immunohistochemical (IHC) markers
- estrogen and progesterone receptor status
- serum tumor markers
Emerging tests
- positron emission tomography (PET)
- gene expression profiling
Treatment algorithm
identification of primary site pending
>1 metastasis: favorable clinicopathologic subtype not identified
>1 metastasis: women with isolated axillary lymphadenopathy (likely primary: breast)
>1 metastasis: women with peritoneal carcinomatosis (likely primary: ovarian)
>1 metastasis: with neuroendocrine features
>1 metastasis: poorly differentiated adenocarcinoma of the midline
>1 metastasis: likely prostate primary
single metastasis
Contributors
Authors
Ross C. Donehower, MD, FACP
Director
Division of Medical Oncology
Johns Hopkins University School of Medicine
Baltimore
MD
Disclosures
RCD declares that he has no competing interests.
Acknowledgements
Dr Ross C. Donehower would like to gratefully acknowledge Dr David Cosgrove and Dr Hatim Hussain, previous contributors to this monograph. DC and HH declare that they have no competing interests.
Peer reviewers
Nikhil Khushalani, MD
Assistant Professor
Department of Medicine
Roswell Park Cancer Institute
Buffalo
NY
Disclosures
NK declares that he has no competing interests.
Zelig Tochner, MD
Associate Professor
Radiation Oncology
Children's Hospital of Philadelphia
Philadelphia
PA
Disclosures
ZT declares that he has no competing interests.
Justin Stebbing, MA, MRCP, MRCPath, PhD
Consultant Medical Oncologist/Senior Lecturer
Department of Medical Oncology
Imperial College/Imperial Healthcare NHS Trust
Charing Cross Hospital
London
UK
Disclosures
JS declares that he has no competing interests.
Differentials
- Squamous or neuroendocrine carcinoma of unknown primary
More DifferentialsGuidelines
- NCCN clinical practice guidelines in oncology: occult primary
- NCCN Clinical Practice Guidelines in Oncology: occult primary
More Guidelines
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