The first 60 days: 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. Below, week by week, is what OnCo's record of Cancer of unknown primary, unfavourable (adenocarcinoma and poorly differentiated carcinoma) says about the first two months: the order is typical, the timing is yours to ask about. Sections appear only where the record has something to say. Orientation, not medical advice.
What happens now
Staging tests establish exactly what and where the cancer is. Everything else follows from the answers.
Exclude favourable subsets; comprehensive genomic profiling of tissue or plasma; assess performance status and lactate dehydrogenase.
Ask which of these were tested and what the results were; see the report reader for what each value means.
These specialties appear in the standard of care for this cancer. In most centres they meet weekly as a tumour board to agree each plan; you can ask when yours was discussed and what was decided.
- PathologistNamed in the standard of care for: Work-up, First line, fit patients, Actionable alterations.
- Medical oncologistNamed in the standard of care for: First line, fit patients, Actionable alterations, Second line.
- Palliative and supportive care teamNamed in the standard of care for: Poor performance status.
A second opinion from a centre that treats many similar cases is normal, not rude; the standard of care tells you what to compare it against.
Each row is a setting from the standard of care, in the order it usually arises. Not all will apply to you; your stage and biomarkers decide which do. The guideline grade, where recorded, says how strong the evidence is.
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.
Best supportive care with early palliative care involvement.
Alternative chemotherapy, PD-1 antibody if not given (nivolumab approved in Japan), or trial entry; trials of antibody-drug conjugates and immunotherapy combinations.
Generated from this cancer's standard of care, biomarkers and open problems. Take the group that matches where you are. To tick, add your own and print, open the one-page appointment sheet.
Newly diagnosed
- What is my exact diagnosis, stage, and grade, and which tests established them?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?These results decide eligibility for targeted therapy, immunotherapy, and trials.
- Which subtype is my cancer, and does that change the recommended treatment?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?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?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?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?Knowing the expected toxicities helps you plan work, family, and supportive care.
- How do the results of CUPISCO apply to someone like me?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?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?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?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?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?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?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)?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?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?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?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?Open problems are where trials and second opinions matter most.
Trials open now for this cancer in OnCo, largest phase first. Joining a trial is a decision like any other: ask what the comparison arm is, whether a placebo is used, and what happens if you leave. The cancer page searches ClinicalTrials.gov live for more.
Much of what helps in the first weeks is free if you know to ask: testing, helplines, rides and lodging, second opinions, trial travel.
- Cancer of unknown primary, unfavourable (adenocarcinoma and poorly differentiated carcinoma): the full pageUnfavourable 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.
- One-page appointment sheetYour questions, the words you may hear, what to bring, and space for the answers. Print it.
- Treatment sequencingWhich treatment tends to follow which, line by line.
- NavigatorStandard of care for your stage, what you have tried, and trials near you.
- Primary tumour: The original tumour where a cancer started.
- Immunohistochemistry (IHC): Staining a tissue slice with antibodies so a protein shows up in colour under the microscope.
- Tumour mutational burden (TMB): How many mutations a tumour has.
- Tumour-agnostic (tissue-agnostic) approval: A tumour-agnostic approval lets a drug be used for any cancer carrying a specific molecular feature, regardless of where it started.
- Microsatellite instability (MSI-H) / mismatch repair deficiency (dMMR): Microsatellite instability is the mark of a broken DNA spell-checker (loss of MLH1, MSH2, MSH6 or PMS2) that leaves thousands of mutations, so the tumour displays abnormal proteins that T cells can recognise.
Every term links to the glossary.