Cancer of unknown primary, unfavourable (adenocarcinoma and poorly differentiated carcinoma)
Unfavourable cancer of unknown primary is the large majority of cases, where a metastatic adenocarcinoma or poorly differentiated carcinoma fits no recognised pattern and its origin cannot be found. Treatment has long been general-purpose platinum chemotherapy, but CUPISCO showed that matching drugs to the tumour's genetic faults after short chemotherapy holds the disease longer.
Overview
Most patients with cancer of unknown primary do not fit a favourable subset. They have adenocarcinoma or poorly differentiated carcinoma in the liver, lungs, bones or several sites at once, are often unwell at diagnosis, and have a poor prognosis; performance status and serum lactate dehydrogenase are the strongest predictors of survival. For thirty years treatment has been empirical: carboplatin with paclitaxel or gemcitabine with cisplatin, regimens chosen because they work across many cancers, with response rates around a third and median survival of about nine to twelve months in trial populations and shorter in the clinic. Randomised trials of classifier-directed site-specific chemotherapy (GEFCAPI 04, Lancet Oncology 2019, and a Japanese trial) did not improve on this, and PD-1 antibodies produced responses in about a fifth of patients in the NivoCUP trial (Annals of Oncology 2022) and the CUPISCO immunotherapy arm, leading to nivolumab's approval for CUP in Japan in 2021.
The CUPISCO trial (Lancet 2024) changed the framing. After three cycles of platinum-based induction chemotherapy, 636 patients with unfavourable CUP whose disease had not progressed were randomised to continue chemotherapy or to switch to molecularly guided therapy chosen by a tumour board from comprehensive genomic profiling, including targeted drugs for actionable alterations and atezolizumab for tumours with high mutational burden or without a target: progression-free survival rose from 4.4 to 6.1 months, a modest but real gain that established genomic profiling as part of the standard work-up. About a third of patients carry an actionable alteration (HER2, BRAF V600E, NTRK fusions, MSI or high tumour mutational burden, and others), and the ESMO 2023 guideline recommends profiling for all patients fit for treatment; circulating tumour DNA is an alternative when tissue is scarce. Trials now test targeted agents, immunotherapy combinations and antibody-drug conjugates with chemotherapy in first line, and DNA-methylation classifiers are being revisited as a route to site-specific immunotherapy choices. Early palliative care and honest discussion of prognosis are part of standard management.
State of the art
- CUPISCO is the first randomised trial to show a benefit from genomically guided therapy in this disease.
- Comprehensive genomic profiling is now recommended for all fit patients.
- Immunotherapy produces durable responses in a minority and is approved in Japan.
Red cards
From the labels and guidelines behind the standard of care. Your team's thresholds win.- Emergency services nowBleeding or bruising
Bleeding that will not stop, black or bloody stools, or unexplained bruising when platelets are expected to be low.
- Emergency services nowHypophysitis or adrenal crisis
Persistent headache with extreme tiredness, nausea, dizziness on standing or low blood pressure. Vomiting, severe weakness or collapse is adrenal crisis.
- Check before combiningFood and drink: Pembrolizumab
No pharmacokinetic interactions expected (antibody). See the irAE guide for toxicity management.
- Check before combiningKidneys: Carboplatin
Dose by Calvert formula using GFR (see the calculators).
- Good to knowImmune-related endocrinopathies (thyroiditis, hypophysitis)
Immunotherapy can attack hormone-producing glands: most often the thyroid (usually ending in an under-active thyroid needing lifelong tablets), and less often the pituitary (hypophysitis) or adrenal glands, which can be life-threatening if missed.
- Good to knowInfusion reactions, hypersensitivity and extravasation
Reactions around the moment a drug is given: chills, fever or breathlessness from antibodies (infusion reactions), true allergy (hypersensitivity, rarely anaphylaxis), and leakage of a damaging drug into tissue around the vein (extravasation).
See all on the product pages:CarboplatinGemcitabine + cisplatinNivolumabPaclitaxel / nab-paclitaxelPembrolizumab·Printable cards in the navigator
Show survival figures (1)
Averages across everyone diagnosed, often years ago. Your stage, subtype, age, fitness and the treatment you receive matter more than the average, and the numbers are improving quickly.
- About four fifths of cancers of unknown primary; most are adenocarcinomas or poorly differentiated carcinomas with liver, lung, bone or multiple metastases, and median survival on empirical chemotherapy is under a year.
- DNA methylation profilingEstablished
- Liquid biopsy (ctDNA)Standard of care
Nothing recorded yet.
Nothing recorded yet.
Also on OnCo: Symptoms and red flags · Early detection roadmap.
Cases by country
No country-level case numbers. This cancer is not mapped to a GLOBOCAN site.
One section per setting: the options named, what each is for, the trials behind them, the recorded trade-offs and the questions to ask.
Exclude favourable subsets; comprehensive genomic profiling of tissue or plasma; assess performance status and lactate dehydrogenase.
Platinum-based doublet (carboplatin-paclitaxel or gemcitabine-cisplatin) for three cycles, then continuation or a switch to molecularly guided therapy where an actionable alteration is found (CUPISCO).
Tumour-agnostic therapies: pembrolizumab or nivolumab for MSI-high or high tumour mutational burden, NTRK inhibitors, BRAF and MEK inhibitors, HER2-directed therapy.
Alternative chemotherapy, PD-1 antibody if not given (nivolumab approved in Japan), or trial entry; trials of antibody-drug conjugates and immunotherapy combinations.
Best supportive care with early palliative care involvement.
Subtypes & biomarkers
top- Adenocarcinoma of unknown primary with liver metastases
- Adenocarcinoma of unknown primary with multiple metastatic sites
- Poorly differentiated carcinoma of unknown primary (non-midline, marker negative)
- Squamous cell carcinoma of unknown primary at non-nodal sites
- Cancer of unknown primary with an actionable alteration (HER2, BRAF, NTRK, MSI-high, high tumour mutational burden)
- Cancer of unknown primary with poor performance status (best supportive care)
- Comprehensive genomic profiling (actionable alterations in about a third)
- Microsatellite instability, tumour mutational burden and PD-L1 (immunotherapy)
- Performance status and serum lactate dehydrogenase (prognosis)
- Immunohistochemistry lineage panel (to exclude favourable subsets)
- Circulating tumour DNA where tissue is insufficient
- Tissue-of-origin classifier (supportive)
How often this target appears
- 1997Carboplatin-paclitaxel established as empirical therapy in phase 2 trials
- 2013Hainsworth phase 2: molecular tissue-of-origin assay-directed therapy
- 2019GEFCAPI 04: site-specific therapy by classifier no better than empirical chemotherapy
- 2021Nivolumab approved for cancer of unknown primary in Japan after NivoCUP
- 2024CUPISCO: molecularly guided therapy after induction chemotherapy lengthens progression-free survival
Dated changes read from the records linked to this cancer: approvals, regulatory steps, reported trials, guideline versions and milestones. Newest first; no date is inferred.
All 12 changes by month →- 2026-09-18This recordCancer of unknown primary, unfavourable (adenocarcinoma and poorly differentiated carcinoma)Facts on this page last checked
When this page itself was last checked or edited.
- 2024Trial resultCUPISCOCUPISCO reported
Median progression-free survival 6.
- 2024MilestoneCUPISCOCUPISCO: molecularly guided therapy after induction chemotherapy lengthens progression-free survival
A milestone in how this cancer is treated.
- 2023GuidelineCancer of unknown primary, unfavourable (adenocarcinoma and poorly differentiated carcinoma)Guideline ESMO Clinical Practice Guideline on cancer of unknown primary 2023: Actionable alterations
Tumour-agnostic therapies: pembrolizumab or nivolumab for MSI-high or high tumour mutational burden, NTRK inhibitors, BRAF and MEK inhibitors, HER2-directed therapy.
- 2023GuidelineCancer of unknown primary, unfavourable (adenocarcinoma and poorly differentiated carcinoma)Guideline ESMO Clinical Practice Guideline on cancer of unknown primary 2023: First line, fit patients
Platinum-based doublet (carboplatin-paclitaxel or gemcitabine-cisplatin) for three cycles, then continuation or a switch to molecularly guided therapy where an actionable alteration is found (CUPISCO).
- 2023GuidelineCancer of unknown primary, unfavourable (adenocarcinoma and poorly differentiated carcinoma)Guideline ESMO Clinical Practice Guideline on cancer of unknown primary 2023: Poor performance status
Best supportive care with early palliative care involvement.
What is in development for Cancer of unknown primary, unfavourable (adenocarcinoma and poorly differentiated carcinoma), drawn from the whole corpus: 2 items. Drugs are grouped by the most advanced trial phase they have reached anywhere; approved treatments sit under standard of care. Technologies are the methods being tested for this cancer, trials are the studies recorded here, and ideas are proposals not yet in a trial.
Trials under way · 1
- A Phase II/III Study of F520 Combined With Paclitaxel Plus Carboplatin in the Treatment of Cancer of Unknown Primary (CUP) · phase 2/3 · Shandong New Time Pharmaceutical Co., LTD
Trials reported · 1
- CUPISCO · phase 2 · 2024 · positive
Open problems and what is being done
Median survival remains under a year for most patients.
Only a third have an actionable alteration and the gain from targeting it is modest.
Patients too unwell for CUPISCO-style induction have no evidence-based option.
The disease is under-studied because it belongs to no organ-based specialty.
Trials
topTrials recruiting now
Country and place are remembered in this browser only. A postcode is sent to OpenStreetMap's Nominatim service to find coordinates when you press the button; nothing else leaves your device.
Landmark trials
Expert centres
topExpert centres
New York · cancer center | United States | 0 | 5,100 | 94,456 | #1 | ||
Baltimore · cancer center | United States | 0 | 2,955 | 41,449 | #10 | ||
Heidelberg · cancer center | Germany | none recorded | 0 | 3,456 | 45,745 | #18 | |
Shanghai · hospital | China | none recorded | 0 | 2,872 | 31,534 | - | |
London · hospital | United Kingdom | none recorded | 0 | 2,376 | 28,940 | - | |
Heidelberg · research institute | Germany | none recorded | 0 | 2,202 | 32,575 | - | |
Lyon · cancer center | France | none recorded | 0 | 1,071 | 14,301 | - | |
Naples · cancer center | Italy | none recorded | 0 | 961 | 15,028 | - | |
Oslo · cancer center | Norway | none recorded | 0 | 936 | 11,600 | - | |
Marseille · cancer center | France | none recorded | 0 | 738 | 7,479 | - | |
Guangzhou · hospital | China | none recorded | 0 | 704 | 7,832 | - | |
Nagoya · cancer center | Japan | none recorded | 0 | 657 | 8,832 | - | |
Lausanne · hospital | Switzerland | none recorded | 0 | 509 | 9,176 | - | |
Osaka · cancer center | Japan | none recorded | 0 | 505 | 4,266 | - | |
Ghent · hospital | Belgium | none recorded | 0 | 495 | 5,334 | - |
These are the things we can measure; they are not a ranking of quality. Each column is a field on the institution record or a count over what OnCo has linked; a centre that treats many patients with Cancer of unknown primary, unfavourable but is thinly recorded here will look small.
Not known: OnCo holds no case-volume or outcome figures for centres, so none are shown. Where a national audit or registry publishes them, the centre's page links to it. Default order: Newsweek rank, then trials for this cancer, then research output.
Questions to ask
topQuestions to ask your oncologist about Cancer of unknown primary, unfavourable
Newly diagnosed
- What is my exact diagnosis, stage, and grade, and which tests established them?Why: Everything else follows from an accurate stage and subtype.
- Which biomarkers have been tested on my tumour (for example Comprehensive genomic profiling, Microsatellite instability, tumour mutational burden and PD-L1, Performance status and serum lactate dehydrogenase, Immunohistochemistry lineage panel, Circulating tumour DNA where tissue is insufficient), and what were the results?Why: These results decide eligibility for targeted therapy, immunotherapy, and trials.
- Which subtype is my cancer, and does that change the recommended treatment?Why: Recognised subtypes for this cancer include Adenocarcinoma of unknown primary with liver metastases, Adenocarcinoma of unknown primary with multiple metastatic sites, Poorly differentiated carcinoma of unknown primary.
- Is germline (inherited) genetic testing recommended for me or my family?Why: Inherited variants can change treatment and matter for relatives.
Work-up
- For my situation (work-up), which of the standard options do you recommend and why?Why: Guideline options include: Exclude favourable subsets; comprehensive genomic profiling of tissue or plasma; assess performance status and lactate dehydrogenase.
First line, fit patients
- For my situation (first line, fit patients), which of the standard options do you recommend and why?Why: Guideline options include: Platinum-based doublet (carboplatin-paclitaxel or gemcitabine-cisplatin) for three cycles, then continuation or a switch to molecularly guided therapy where an actionable alteration is found (CUPISCO).
- Am I a candidate for Carboplatin, Paclitaxel / nab-paclitaxel, Gemcitabine + cisplatin, and what side effects should I expect?Why: Knowing the expected toxicities helps you plan work, family, and supportive care.
- How do the results of CUPISCO apply to someone like me?Why: Trial populations differ from individual patients; ask how closely you match.
Actionable alterations
- For my situation (actionable alterations), which of the standard options do you recommend and why?Why: Guideline options include: Tumour-agnostic therapies: pembrolizumab or nivolumab for MSI-high or high tumour mutational burden, NTRK inhibitors, BRAF and MEK inhibitors, HER2-directed therapy.
- Am I a candidate for Pembrolizumab, Nivolumab, and what side effects should I expect?Why: Knowing the expected toxicities helps you plan work, family, and supportive care.
Second line
- For my situation (second line), which of the standard options do you recommend and why?Why: Guideline options include: Alternative chemotherapy, PD-1 antibody if not given (nivolumab approved in Japan), or trial entry; trials of antibody-drug conjugates and immunotherapy combinations.
- Am I a candidate for Nivolumab, Pembrolizumab, and what side effects should I expect?Why: Knowing the expected toxicities helps you plan work, family, and supportive care.
- How do the results of A Phase II/III Study of F520 Combined With Paclitaxel Plus Carboplatin in the Treatment of Cancer of Unknown Primary (CUP) apply to someone like me?Why: Trial populations differ from individual patients; ask how closely you match.
Poor performance status
- For my situation (poor performance status), which of the standard options do you recommend and why?Why: Guideline options include: Best supportive care with early palliative care involvement.
Any stage
- Are there clinical trials I could join, for example of CUPISCO, A Phase II/III Study of F520 Combined With Paclitaxel Plus Carboplatin in the Treatment of Cancer of Unknown Primary (CUP), Comprehensive genomic profiling, Liquid biopsy (ctDNA)?Why: Trials are how the next standard of care is set; asking early keeps options open.
- Would a second opinion at a high-volume centre change anything, and can you help arrange it?Why: Rare or high-stakes decisions benefit from a centre that treats many similar patients.
- What supportive care (symptom control, nutrition, exercise, mental health, financial help) is available from the start?Why: Supportive care improves quality of life and helps patients complete treatment.
- I read that “Median survival remains under a year for most patients”. How does that affect my plan?Why: Open problems are where trials and second opinions matter most.
- I read that “Only a third have an actionable alteration and the gain from targeting it is modest”. How does that affect my plan?Why: Open problems are where trials and second opinions matter most.
Newly diagnosed? Read the first 60 days with Cancer of unknown primary, unfavourable, then print the one-page appointment sheet with room for the answers.
Print this page for your appointment (your browser's print command). These prompts are for discussion; your clinical team knows your case.
Direct links plus the targets, companies, and technologies of this cancer's products.
technologies
8targets
4drugs
5companies
3terms
5trials
2bottlenecks
1key papers
3Comprehensive genomic profiling at diagnosis is now justified for unfavourable cancer of unknown primary, with a switch to a matched drug after induction chemotherapy when an actionable target is found.
The split between favourable and unfavourable cancer of unknown primary on OnCo, and the treatment on each page, follow this guideline.
Predicting the primary site by gene expression and treating accordingly is not better than empirical chemotherapy, so guidelines do not recommend it; the field moved to genomic profiling for actionable targets instead.
Latest papers
topQuery for this cancer: (TITLE:"Cancer of unknown primary, unfavourable" OR ABSTRACT:"Cancer of unknown primary, unfavourable" OR TITLE:"adenocarcinoma and poorly differentiated carcinoma" OR ABSTRACT:"adenocarcinoma and poorly differentiated carcinoma" OR TITLE:"Unfavourable-risk CUP" OR ABSTRACT:"Unfavourable-risk CUP" OR TITLE:"Poor-prognosis CUP" OR ABSTRACT:"Poor-prognosis CUP" OR TITLE:"CUP adenocarcinoma with liver or multiple metastases" OR ABSTRACT:"CUP adenocarcinoma with liver or multiple metastases" OR TITLE:"Non-specific CUP" OR ABSTRACT:"Non-specific CUP") AND (treatment OR therapy OR trial OR survival OR diagnosis). Results are unfiltered search hits about Cancer of unknown primary, unfavourable (adenocarcinoma and poorly differentiated carcinoma), not a curated reading list.
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