Medical Oncologist
CION Cancer Clinics
Getting tumour and germline tests in the right order | CION Cancer Clinics
The order of genetic tests matters. Test the person with cancer before well relatives, and get any result that could change a decision before that decision is made. The wrong order can waste biopsy tissue, delay answers and leave relatives with negative results that settle nothing. This page explains which test usually comes first, how that changes by situation, and what to ask your care team. At CION Cancer Clinics in Hyderabad, our oncologists review your family history with you and guide you to the right genetic counselling and testing.
NG
Medically reviewed by Dr. Naresh GunduConsultant Medical Oncologist · MBBS, DNB (Internal Medicine), DM (Medical Oncology, AIIMS) · last reviewed September 2026, next review due September 2027
17+specialists on panel
15,000+patients treated
35+centres across Telangana & AP
4.8★ / 800+Google rating
On this page
- Does it matter which genetic test comes first?
- Which order fits which situation?
- What does a sensible order usually look like?
- The terms used when planning the order, in plain language
- What goes wrong when the order is wrong?
- Four things families assume about the order of tests
- What this page cannot tell you
- Common questions about the order of genetic tests
The short answer
Does it matter which genetic test comes first?
Yes. The order decides how quickly you get a useful answer, whether precious tissue is used well, and how much the family pays in the end. The general rule is simple. Test the person with cancer before well relatives, and get any result that could change a decision before that decision is made.
Three kinds of order that matter
The first is within the patient: tumour test, germline test, or both together. The second is within the family: the relative who had cancer is tested before those who are well. The third is against treatment: a germline answer that could change surgery or a medicine should arrive before that choice is final.
When order matters less
If neither result would change the next step, the order makes little difference. Many people start treatment straight away while genetic results are still pending. Your oncologist decides whether any result truly has to come first, and will tell you why.
Getting the order right is not about speed alone. It is about asking each question when its answer can still be used.Situation by situation
Which order fits which situation?
There is no single sequence for everyone. These are the situations your care team most often has to plan around.
Treatment is urgent
The tumour test usually goes first, or both are sent together. The germline test follows or runs alongside, so treatment is not held up waiting for a family answer.
A surgery choice may hinge on it
If an inherited fault could change the type of operation, the germline result should come before the surgery is fixed. Surgery to lower future risk is one option among several, and it is covered on our risk-reduction pages.
The biopsy was small
Tissue from a small biopsy can run out. It is kept for the tumour test. The germline test uses blood or saliva, so it never competes for the tissue.
Ask the team
- Is there enough tissue for every test planned?
- Which test gets the tissue first?
The family is asking, not the patient
Test the relative who had cancer first, if they are willing. If nobody affected is alive, a stored tissue block may still be tested. Only then are well relatives tested more widely.
Not sure whether this applies to you?
Ask an oncologistFrom diagnosis to family
What does a sensible order usually look like?
-
Diagnosis and biopsy
The pathologist confirms the cancer. The tissue is stored in a wax block, which stays available for later tests.
-
Tumour test, if treatment needs it
Your oncologist orders it to look for changes a medicine can target. That result guides the treatment plan.
-
Germline test in the patient
Added when the cancer type, a tumour finding or the family history points to an inherited cause, after counselling.
-
The result is explained
A counsellor goes through the germline result and what it means for you, your treatment and your relatives.
-
Relatives are tested for that exact fault
If a fault is found, brothers, sisters and children can have a simple targeted test. It is quicker and cheaper than a full panel.
-
Screening plans follow the results
Relatives who carry the fault get a screening plan. Those who do not usually return to ordinary advice, though family history still counts.
Words you will hear
The terms used when planning the order, in plain language
- Affected relative
- A family member who has or had cancer. Testing them first gives the clearest answer.
- Unaffected relative
- A family member who has never had cancer. A negative result in them means less if nobody affected was tested.
- Cascade testing
- Testing relatives, one circle of the family at a time, for a fault already found in the family.
- Targeted test
- A test that looks only for the one fault already known in the family. It is simpler and cheaper than a panel.
- Uninformative negative
- A negative result that cannot rule out an inherited fault, because the family's fault was never identified.
- Germline
- Present from birth in every cell, and able to pass to children. Somatic means found only in the tumour.
Leave a number, we will call you
One field. No form to fill in, and no charge for the call.
Side by side
What goes wrong when the order is wrong?
A helpful order
An unhelpful order
The relative with cancer is tested first
A well relative's negative result means little
Germline answer arrives before surgery is fixed
The answer comes after the operation it could have changed
Tissue is kept for the tumour test
Tissue runs out and a second biopsy is needed
Relatives have a cheap targeted test
Relatives pay for full panels one by one
A tumour flag is checked in blood
A tumour flag is ignored, or wrongly assumed inherited
Commonly believed
Four things families assume about the order of tests
"The relative who is most worried should be tested first."
The relative who had cancer should go first. Their result tells everyone else whether there is a fault to look for. A well relative tested first can get a negative that settles nothing.
"The order does not matter as long as everyone is tested."
It matters a great deal. The wrong order wastes money, uses up tissue and gives negative results that falsely reassure.
"Treatment has to wait for every genetic result."
Most treatment can start while results are pending. Your oncologist will say if one particular result must come first, and why.
"If the patient has died, the right order is impossible."
Not always. A tissue block stored after an old operation or biopsy can sometimes be tested. If not, a counsellor plans testing of well relatives and explains its limits.
Being straight with you
What this page cannot tell you
It cannot set the order for your family. That depends on who had which cancer, who is alive and willing, what tissue is stored and what treatment is being planned. Your oncologist and a genetic counsellor work that out together.
It cannot read the results once they arrive
A result only makes sense in the light of what was tested before it. What your specific variant means is a question for the counsellor who ordered the test.
Who this does not apply to
Most people with cancer need only a tumour test, or no genetic test at all. If your family history is unremarkable and nothing in the tumour report points to an inherited cause, there may be no germline question to put in order.
Families spread across districts and states
In many Telangana families, the relative who had cancer lives far from the one asking. Blood samples can often be collected locally and couriered. It is still worth the effort to test that relative first.
Unsure who in your family should be tested first? Call the helpline and describe the family. We will help you plan it.Questions we are asked
Common questions about the order of genetic tests
Should my tumour test come before my blood test?
Often, yes, when treatment depends on it. But in some cancers both are sent together, and sometimes the germline test is more urgent. Your oncologist decides based on the cancer type and what decision is coming next.
Why should the relative with cancer be tested first?
Because their result shows whether the family has a fault to look for. If they carry one, relatives get a cheap targeted test with a clear answer. If a well relative goes first and is negative, nobody knows whether the family fault was simply missed.
What if the relative with cancer does not want testing?
That is their right, and it should be respected. A counsellor can still assess the family history and may offer testing to a well relative. The limits of a negative result in that situation will be explained before the test.
Should I wait for the germline result before surgery?
Only if the result could change the operation. Ask your surgeon that exact question. If the answer is yes, ask how long the result will take and whether surgery can safely wait. Often it can.
Does treatment wait for genetic results?
Usually not. Most treatments start on the standard plan while results are pending, and the plan is adjusted if a result changes it. Your oncologist will say if a particular result must come first.
Can a well relative go first if nobody affected is alive?
Yes, after checking whether a stored tissue block from the relative who died can be tested. If not, the well relative is usually offered a panel. A negative result is less reassuring in that case, and screening may still follow the family history.
My tumour test flagged a possible inherited change. What next?
Ask your oncologist for a genetic counselling referral. A blood test will show whether the change was inherited. Until that result is back, do not tell relatives they are at risk. Many such flags turn out to be in the tumour only.
How much does the order change the family's costs?
A great deal. Once a fault is known, each relative needs only a targeted test, which costs far less than a panel. Without that known fault, each relative may need a full panel. Ask the lab for both prices before you decide.
Your Specialists
Meet CION's oncologists. Bring your family history or genetic report to them.
Our medical oncologists see people with a strong family history of cancer, arrange genetic counselling and testing where it fits, and plan the checks that follow.
Medical Oncologist
Dr. C. Raghavendra Reddy
MBBS(Gold Medal), DNB(General Medicine), DM(Medical Oncology)(Gold Medal)
Medical Oncologist
Dr. Bharati Devi Gorantla
MBBS, MD(General Medicine), DM(Medical Oncology)(Adyar,Chennai), ECMO, MRCP SCE(UK)
Medical Oncologist
Dr. Owais Mohammed
MBBS, MD (General Medicine), DrNB (Medical Oncology), ECMO, MRCP SCE (Medical Oncology) (UK)
Medical Oncologist
Medical Oncologist
Want a specific doctor for your case? Mention them when booking.
Book Free ConsultationBook an appointment with our specialist
Share your name and number — we'll call you back within 30 minutes to schedule your consultation.
Sources
- National Cancer Institute — Genetic Testing for Inherited Cancer Susceptibility Syndromes
- NCCN — Genetic/Familial High-Risk Assessment Guidelines
- National Cancer Institute — Biomarker Testing for Cancer Treatment
- Cancer Research UK — Genetic testing for cancer risk genes
This page is general information, not a prescription. Do not change or stop any treatment based on what you read here. If anything is worrying you, contact your own treating team — or call our helpline and we will help you reach the right specialist.
Keep reading
Related pages
Having both tests at the same timeWhen sending both together beats waitingWhen a tumour result triggers a germline testThe tumour findings that should lead to a blood testTesting an affected relative firstWhy the relative with cancer goes firstHow cascade testing worksHow relatives are tested once a fault is found
Talk to us
Not sure who in the family should be tested first?
Tell us who had cancer, who is alive and what has been tested so far. We will help you plan the order so the answers are useful. One helpline serves every CION centre.