Cancer of Unknown Primary Flashcards
How will cancer often present?
As a result of symptoms due to the primary site of the tumour
Why might cancer not always present as a result of symptoms due to the primary site of the tumour?
Because sometimes the cancer is able to metastasise before the primary site is large enough to be detected
How to carcinomas of unknown primary (CUP) differ from known primary tumours?
They tend to have early dissemination, unpredictable metastatic pattern, aggressive nature, and an absence of symptoms from the primary site
What is CUP defined as?
The detection of one or more sites of metastatic tumours for which investigations have failed to identify the primary site
What % of cancers are CUP?
Up to 5%
What is the median age of presentation of CUP?
60 years
What % of patients with CUP present with multiple sites of presentation?
50%
What are the most common sites of presentation of CUP?
- Liver
- Bones
- Lungs
- Lymph nodes
What is the usual histological diagnosis in CUP?
Adenocarcinoma or poorly differentiated carcinoma
What will happen with different tumours, with respect to spread?
They will spread in different patterns
i know this is a bit shit sorry lol
What might the differing spread of different tumours be related to?
Chemokine and their receptors expression by the tumour and stromal cells
What will the clinical presentation of CUP depend on?
The location of disease sites
What non-specific symptoms are common in CUP?
- Anorexia
- Weight loss
- Fatigue
What is step 1 in the approach to patients with CUP?
Search for primary site
What is step 2 in the approach to patients with CUP?
Rule out potentially treatable or curable tumours
What is step 3 in the approach to patients with CUP?
Characterise the specific clinicopathological entity, and then treat the patient
In what manner should patients with favourable subsets of CUP be treated?
Consider curative intent
In what manner should patients with unfavourable subsets of CUP be treated?
Palliative intent
What % of patients with CUP have a primary site identified antemortem?
20%
What % of patients with CUP have an unidentified primary site at postmortem?
70%
Where are primary sites most frequently detected in CUP?
- Lung
- Pancreas
- GI
- Gynaecological
What initial investigations are done in CUP?
- Complete history and physical examination
- FBC
- Serum biochemistry and liver function
- Serum tumour markers
- Urinalysis and stool testing for occult blood
- Chest x-ray
- Symptom-directed endoscopy
- Imaging of thorax, abdomen, and pelvis (MRI, CT, or PET)
- Biopsy for histology (any site of disease)§w
What can CUP be classified into on the basis of light microscopy?
- Well to moderately differentiated adenocarcinoma
- Poorly or undifferentiated adenocarcinoma
- Squamous cell carcinoma
- Undifferentiated carcinoma
What malignancies can be identified by immunohistochemistry?
- Neuroendocrine tumours
- Lymphomas
- Germ cell tumours
- Melanomas
- Sarcomas
- Serous tumours (ovarian, peritoneal, uterine)
- Embryonal malignancies
Who should patients with CUP be referred to to advise on required investigations?
Oncologist
Why should patients with CUP be referred to an oncologist for advice on investigations?
There should be concern about over-investigating the patient
Why should there be concern about over-investigating the patient with CUP?
It will have a cost effect, and potentially can delay the initiation of appropriate treatment for the patient
What needs to be balanced when investigating CUP?
The need for sufficient tests to plan the management and the treatment of the disease
How are patients with CUP with an incurable malignancy that is widely metastatic treated?
The combination systemic chemotherapy that is most appropriate
What will the choice of treatment depend on in incurable CUP that is widely metastatic?
The best assessment of the likely primary site and consideration of the performance status of the patient
Where is radiotherapy useful in incurable CUP?
For specific sites of pain or discomfort
What is the aim of treatment for incurable CUP?
Palliative, to improve quality of life
When might treatment be discontinued in incurable CUP?
If the patient is no longer gaining benefit or improvement in symptoms
What is the prognosis for patients with well or moderated differentiated adenocarcinoma of unknown primary?
Poor
Why do patients with well or moderate differentiated adenocarcinoma of unknown primary have a poor prognosis?
Because 90% have low response rate to chemotherapy
What can patients with potential ovarian or peritoneal sites respond very well too?
Appropriate chemotherapy
What % of patients with potential ovarian or peritoneal sites achieve complete remission on appropriate chemotherapy?
40%
How can patients with axillary lymph node metastasis in CUP be treated?
As breast cancer, and may require a modified radical mastectomy
What % of patients with CUP have poorly differentiated carcinoma or adenocarcinoma?
30%
Why is having poorly differentiated carcinoma or adenocarcina shit?
- Demonstrate poor response to systemic chemotherapy
- Poor outcome and short survival
- Younger median age (40 years)
- Rapid progression of symptoms
What are the most common sites of involvement of poorly differentiated carcinoma or adenocarcinoma CUP?
- Lymph nodes
- Mediastinum
- Retroperitoneum
What can rarely happen with poorly differentiated carcinoma or adenocarcinoma CUP?
Excellent responses and improved survival
What can predict which patients with poorly differentiated carcinoma or adenocarcinoma will have excellent responses?
No identified factors to predict this
What treatment should be considered for patients with CUP with a single site of metastasis?
Surgical resection and treatment with radiotherapy
What is the advantage of surgical resection and radiotherapy in CUP patients with a single site of metastasis?
Can produce significant periods of disease-free survvival in some patients
What should the presence of osteoblastic bone metastasis in a male patient be considered for?
Empirical hormone therapy (regardless of PSA)
What is the median survival for a patient with CUP?
6-9 months
What is the median survival for a patient with CUP with 1-2 sites of involvement, non-adenocarcinoma, and no involvement of liver, bone, or adrenal gland?
40 months
i dont think you really have to know this lol
What are the adverse prognostic factors for CUP?
- Adenocarcinoma histology
- Increasing number of involved organ sites
- Hepatic or adrenal involvement
- Supraclavicular lymph node involvement
- Male gender
- Poor performance status
- Weight loss (>10% of body mass)