Cancer of unknown primary, favourable subsets: the decisions you may face
7 treatment settings, 5 with more than one named option. Each section lays out the options the standard of care names, what each is for, the trials behind them with their recorded results, the side effects and cautions on record, and questions to ask. Built from the cancer page's standard-of-care rows; nothing here is advice for your case.
Histology with directed immunohistochemistry, CT of chest, abdomen and pelvis, sex-specific examinations and tumour markers, PET-CT for cervical node squamous carcinoma and single-site disease.
Histopathology means looking at cancer cells under a microscope, and immunohistochemistry stains them for specific proteins. Together they are still the foundation of every diagnosis.
- Cheap, fast, universal
- Companion diagnostic for most targeted drugs
A CT scan is a fast 3D X-ray that shows the size and shape of tumours and whether they have spread.
- Fast, ubiquitous
- Sub-millimetre resolution
- Standard for RECIST response
PET and CT in one machine, so hot spots on the PET are pinned to exact locations on the CT.
- Anatomy plus biology
- Standard for lymphoma, lung, melanoma, head and neck staging
In testicular and other germ cell cancers three blood tests, AFP, beta-hCG and LDH, are part of the staging itself: their levels after surgery sort patients into good, intermediate and poor risk groups that fix how many cycles of chemotherapy they get, and their return to normal defines cure.
- Part of staging and directly sets chemotherapy intensity
- Rising markers define relapse without imaging
- Cheap and universally available
No trial record is attached to this row yet. The trials tab lists what is recruiting and the landmark trials for this cancer.
- Subjective scoring
- Single-site sampling misses heterogeneity
- Anatomic only; cannot distinguish scar from live tumour
- Radiation dose
- Poor for brain, marrow, and small peritoneal disease
- CT radiation added to PET dose
- Seminoma and some non-seminomas are marker negative
- Benign causes of elevation, including liver disease and haemolysis
- Assay differences require following one laboratory
- Between Histopathology & immunohistochemistry, CT (computed tomography), PET/CT and the other options, which do you recommend for me, and what about my case would make you choose differently?Why: Guidelines list several reasonable options; the choice turns on details of your tumour, your health and your priorities.
- What is each option trying to achieve: cure, long control, or relief of symptoms, and over what time?Why: The aim shapes how much side effect and disruption is worth accepting.
- What happens if I delay, or decline this step for now? Is the decision reversible?Why: Some decisions can wait for a second opinion or a trial slot; others cannot. Knowing which is part of the choice.
- Does your recommendation follow the current guideline (ESMO Clinical Practice Guideline on cancer of unknown primary 2023), and if it departs from it, why?Why: Departures from guidelines are sometimes right for an individual; they should be explained.
- For my situation (work-up), which of the standard options do you recommend and why?Why: Guideline options include: Histology with directed immunohistochemistry, CT of chest, abdomen and pelvis, sex-specific examinations and tumour markers, PET-CT for cervical node squamous carcinoma and single-site disease.
Add these to your appointment list, or take the full question set for this cancer.
Axillary node adenocarcinoma in a woman
Treat as node-positive breast cancer: axillary dissection, breast radiotherapy or mastectomy, systemic therapy by receptor status.
IMRT and IGRT shape the radiation beam to the tumour's outline from multiple angles and check the patient's position with a scan before every session, so surrounding organs receive less dose. Fewer, larger doses are now standard in breast and prostate cancer, but a low-dose bath still spreads across normal tissue.
- Conformal dose, fewer side effects
- Hypofractionation saves visits
No trial record is attached to this row yet. The trials tab lists what is recruiting and the landmark trials for this cancer.
- Low-dose bath to normal tissue
- Motion management
- Is IMRT / IGRT (modern external beam) the only reasonable path for me, or is there a trial, a different sequence or a wait-and-see option?Why: A single standard does not mean a single choice; timing and trials are decisions too.
- What is each option trying to achieve: cure, long control, or relief of symptoms, and over what time?Why: The aim shapes how much side effect and disruption is worth accepting.
- What happens if I delay, or decline this step for now? Is the decision reversible?Why: Some decisions can wait for a second opinion or a trial slot; others cannot. Knowing which is part of the choice.
- Does your recommendation follow the current guideline (ESMO Clinical Practice Guideline on cancer of unknown primary 2023), and if it departs from it, why?Why: Departures from guidelines are sometimes right for an individual; they should be explained.
- For my situation (axillary node adenocarcinoma in a woman), which of the standard options do you recommend and why?Why: Guideline options include: Treat as node-positive breast cancer: axillary dissection, breast radiotherapy or mastectomy, systemic therapy by receptor status.
Add these to your appointment list, or take the full question set for this cancer.
Peritoneal serous carcinoma in a woman
Treat as advanced ovarian cancer: cytoreductive surgery and carboplatin-paclitaxel with maintenance as indicated.
Carboplatin is a platinum chemotherapy that crosslinks DNA; it is part of the standard pre-surgery regimen for triple-negative breast cancer.
A microtubule poison discovered in the Pacific yew tree, among the most used chemotherapies in breast, lung, and ovarian cancer.
No trial record is attached to this row yet. The trials tab lists what is recruiting and the landmark trials for this cancer.
- Dose by Calvert formula using GFR (see the calculators).
- Between Carboplatin and Paclitaxel / nab-paclitaxel, which do you recommend for me, and what about my case would make you choose differently?Why: Guidelines list several reasonable options; the choice turns on details of your tumour, your health and your priorities.
- What is each option trying to achieve: cure, long control, or relief of symptoms, and over what time?Why: The aim shapes how much side effect and disruption is worth accepting.
- What happens if I delay, or decline this step for now? Is the decision reversible?Why: Some decisions can wait for a second opinion or a trial slot; others cannot. Knowing which is part of the choice.
- Does your recommendation follow the current guideline (ESMO Clinical Practice Guideline on cancer of unknown primary 2023), and if it departs from it, why?Why: Departures from guidelines are sometimes right for an individual; they should be explained.
- For my situation (peritoneal serous carcinoma in a woman), which of the standard options do you recommend and why?Why: Guideline options include: Treat as advanced ovarian cancer: cytoreductive surgery and carboplatin-paclitaxel with maintenance as indicated.
- Am I a candidate for Carboplatin, Paclitaxel / nab-paclitaxel, and what side effects should I expect?Why: Knowing the expected toxicities helps you plan work, family, and supportive care.
Add these to your appointment list, or take the full question set for this cancer.
Cervical node squamous carcinoma
Treat as head and neck cancer: HPV and EBV testing, neck dissection or chemoradiotherapy with cisplatin.
Cisplatin is the original platinum chemotherapy, discovered by accident in 1965; it cures testicular cancer and makes radiation work better in cervical and head and neck cancer.
IMRT and IGRT shape the radiation beam to the tumour's outline from multiple angles and check the patient's position with a scan before every session, so surrounding organs receive less dose. Fewer, larger doses are now standard in breast and prostate cancer, but a low-dose bath still spreads across normal tissue.
- Conformal dose, fewer side effects
- Hypofractionation saves visits
No trial record is attached to this row yet. The trials tab lists what is recruiting and the landmark trials for this cancer.
- Dose reduce or avoid for CrCl below 60 (carboplatin is the alternative).
- Low-dose bath to normal tissue
- Motion management
- Between Cisplatin and IMRT / IGRT (modern external beam), which do you recommend for me, and what about my case would make you choose differently?Why: Guidelines list several reasonable options; the choice turns on details of your tumour, your health and your priorities.
- What is each option trying to achieve: cure, long control, or relief of symptoms, and over what time?Why: The aim shapes how much side effect and disruption is worth accepting.
- What happens if I delay, or decline this step for now? Is the decision reversible?Why: Some decisions can wait for a second opinion or a trial slot; others cannot. Knowing which is part of the choice.
- Does your recommendation follow the current guideline (ESMO Clinical Practice Guideline on cancer of unknown primary 2023), and if it departs from it, why?Why: Departures from guidelines are sometimes right for an individual; they should be explained.
- For my situation (cervical node squamous carcinoma), which of the standard options do you recommend and why?Why: Guideline options include: Treat as head and neck cancer: HPV and EBV testing, neck dissection or chemoradiotherapy with cisplatin.
- Am I a candidate for Cisplatin, and what side effects should I expect?Why: Knowing the expected toxicities helps you plan work, family, and supportive care.
Add these to your appointment list, or take the full question set for this cancer.
Midline poorly differentiated carcinoma in a young man
Treat as extragonadal germ cell tumour with cisplatin-based combination chemotherapy.
Cisplatin is the original platinum chemotherapy, discovered by accident in 1965; it cures testicular cancer and makes radiation work better in cervical and head and neck cancer.
Etoposide is a chemotherapy from the mayapple plant, essential to curing testicular cancer (BEP), treating small-cell lung cancer, lymphomas, childhood sarcomas and leukaemias, and used in transplant conditioning.
In testicular and other germ cell cancers three blood tests, AFP, beta-hCG and LDH, are part of the staging itself: their levels after surgery sort patients into good, intermediate and poor risk groups that fix how many cycles of chemotherapy they get, and their return to normal defines cure.
- Part of staging and directly sets chemotherapy intensity
- Rising markers define relapse without imaging
- Cheap and universally available
No trial record is attached to this row yet. The trials tab lists what is recruiting and the landmark trials for this cancer.
- Dose reduce or avoid for CrCl below 60 (carboplatin is the alternative).
- Reduce to 75% for CrCl 15-50.
- Seminoma and some non-seminomas are marker negative
- Benign causes of elevation, including liver disease and haemolysis
- Assay differences require following one laboratory
- Between Cisplatin, Etoposide and AFP, hCG and LDH in germ cell tumours (IGCCCG risk groups), which do you recommend for me, and what about my case would make you choose differently?Why: Guidelines list several reasonable options; the choice turns on details of your tumour, your health and your priorities.
- What is each option trying to achieve: cure, long control, or relief of symptoms, and over what time?Why: The aim shapes how much side effect and disruption is worth accepting.
- What happens if I delay, or decline this step for now? Is the decision reversible?Why: Some decisions can wait for a second opinion or a trial slot; others cannot. Knowing which is part of the choice.
- Does your recommendation follow the current guideline (ESMO Clinical Practice Guideline on cancer of unknown primary 2023), and if it departs from it, why?Why: Departures from guidelines are sometimes right for an individual; they should be explained.
- For my situation (midline poorly differentiated carcinoma in a young man), which of the standard options do you recommend and why?Why: Guideline options include: Treat as extragonadal germ cell tumour with cisplatin-based combination chemotherapy.
- Am I a candidate for Cisplatin, Etoposide, and what side effects should I expect?Why: Knowing the expected toxicities helps you plan work, family, and supportive care.
Add these to your appointment list, or take the full question set for this cancer.
Neuroendocrine carcinoma of unknown primary
Platinum-etoposide as for extrapulmonary neuroendocrine carcinoma; somatostatin analogues and radioligand therapy for well-differentiated tumours.
Platinum plus etoposide has been the chemotherapy backbone of small-cell lung cancer for over 40 years, and is now given with immunotherapy.
Monthly injections of a synthetic hormone that both quiets tumour hormone symptoms and slows tumour growth, the first treatment for most neuroendocrine tumours.
Lutetium-177 dotatate was the first modern radioligand therapy (2018), for neuroendocrine tumours, and is now used in first line.
No trial record is attached to this row yet. The trials tab lists what is recruiting and the landmark trials for this cancer.
| Side effect | Any grade | Grade 3+ |
|---|---|---|
| Lymphopenia · NETTER-1; grade 3-4 rates | - | 44% |
| GGT increased · NETTER-1; grade 3-4 rates | - | 20% |
| Vomiting · NETTER-1; grade 3-4 rates | - | 7% |
| Nausea · NETTER-1; grade 3-4 rates | - | 5% |
Rates from the label or pivotal trial as recorded on the product page; each grade 3+ figure links to its source.
- Between Platinum + etoposide (EP / CE), Somatostatin analogues (octreotide, lanreotide) and Lutetium-177 dotatate, which do you recommend for me, and what about my case would make you choose differently?Why: Guidelines list several reasonable options; the choice turns on details of your tumour, your health and your priorities.
- What is each option trying to achieve: cure, long control, or relief of symptoms, and over what time?Why: The aim shapes how much side effect and disruption is worth accepting.
- Which side effects of Lutetium-177 dotatate are most likely for me, which are reversible, and which would make us stop?Why: The recorded rates below come from labels and trials; your own risk depends on dose, other medicines and your health.
- What happens if I delay, or decline this step for now? Is the decision reversible?Why: Some decisions can wait for a second opinion or a trial slot; others cannot. Knowing which is part of the choice.
- Does your recommendation follow the current guideline (ESMO Clinical Practice Guideline on cancer of unknown primary 2023), and if it departs from it, why?Why: Departures from guidelines are sometimes right for an individual; they should be explained.
- For my situation (neuroendocrine carcinoma of unknown primary), which of the standard options do you recommend and why?Why: Guideline options include: Platinum-etoposide as for extrapulmonary neuroendocrine carcinoma; somatostatin analogues and radioligand therapy for well-differentiated tumours.
- Am I a candidate for Platinum + etoposide (EP / CE), Somatostatin analogues (octreotide, lanreotide), Lutetium-177 dotatate, and what side effects should I expect?Why: Knowing the expected toxicities helps you plan work, family, and supportive care.
Add these to your appointment list, or take the full question set for this cancer.
Single metastasis
Resection or stereotactic radiotherapy with curative intent.
Stereotactic body radiotherapy converges multiple beams with sub-millimetre accuracy to deliver tumour-destroying doses in one to five outpatient sessions, doing the job of surgery for inoperable early lung cancer and for metastases in liver, spine and brain. Tumour size and location limit its use, and late toxicity is a concern near the central airways.
- Ablative doses with minimal recovery
- Outpatient
No trial record is attached to this row yet. The trials tab lists what is recruiting and the landmark trials for this cancer.
- Size and location limits
- Late toxicity near central airways
- Is SBRT / SABR (stereotactic radiotherapy) the only reasonable path for me, or is there a trial, a different sequence or a wait-and-see option?Why: A single standard does not mean a single choice; timing and trials are decisions too.
- What is each option trying to achieve: cure, long control, or relief of symptoms, and over what time?Why: The aim shapes how much side effect and disruption is worth accepting.
- What happens if I delay, or decline this step for now? Is the decision reversible?Why: Some decisions can wait for a second opinion or a trial slot; others cannot. Knowing which is part of the choice.
- Does your recommendation follow the current guideline (ESMO Clinical Practice Guideline on cancer of unknown primary 2023), and if it departs from it, why?Why: Departures from guidelines are sometimes right for an individual; they should be explained.
- For my situation (single metastasis), which of the standard options do you recommend and why?Why: Guideline options include: Resection or stereotactic radiotherapy with curative intent.
Add these to your appointment list, or take the full question set for this cancer.