There is no universal method of cancer detection that can be used with all tumors. For example PSA measurement is a good method for screening in prostate cancer. ENDOSCOPY is the main source of early colorectal cancer detection. MAMMOGRAPHY is the choice for breast cancer.

In the case of the population in high risk for hepatoma ultrasound imaging is a good screening method.

Dear Hariom

Cancer is a histopathological diagnosis; ie. it needs certification/confirmation as a cancer by examination of a biopsy specimen before any definitive treatment can be offered (except in very rare situations).

All investigations generally aim at methods for obtaining a biopsy specimen for the confirmation and for staging.

These are generally done once someone develops a suspicious symptom or sign.

Sometimes mass screening procedures are undertaken and these include physical examination, imaging, scopies, biochemistry, etc. They too finally lead to histology

Nowadays, PSA seems to be serving as confirmatory test for prostate cancer.

Narayanan

Harlom is asking for the best method for early detection. That means that he is asking for screening methods not for confirmatory ones. Histopathology is confirmatory but it is not a method for early detection.

There are many types of cancer in different places of the body. It is necessary to use several methods, like radiological, endoscopic, biopsy cytology, serum markers, genetics and so on.....

Thanks to Tomas Koltai, luis Rodrigo, Narayanan Bhattathiri and Olena Polyakova for giving a valuable information about the cancer diagnosis.

It is correct that suggested methods are widely used for confirmation of cancer.

What about the possibilities of non-invasive diagnosis of cancer based on body fluids such as saliva and blood etc for the early stage of detection of cancer.

Imaging such as ultrasound, X-ray based imaging (CT) and MRI etc. are commonly used for cancer screening as non-invasive method. Which one is more better and accurate technique for the detection and confirmation of cancer ??

So please share your valuable views and suggestions for the same...

Dear Olena

You are very right; PSA is not equivalent to Histopathology. That is why I just stated that '....there seems to be a tendency....'

However, take the case of finasteride: it is used for the treatment of BPH and it brings down PSA levels. It has also been used along with bicalutamide for the treatment of prostate cancer, on this ground. I think the time is not far off when it or some other drug will be used for cancer prostate' just on the basis of its ability to decrease PSA. Of course there is logic in this; yet it is fraught with danger too. Ultimately, all these is likely to depend on the interests of drug companies!

See the links

https://www.ncbi.nlm.nih.gov/m/pubmed/9649261/

https://academic.oup.com/annonc/article/15/6/974/130041

Narayanan

You are right Mohit. May be Youden's index could be helpful! Few approaches using this in Prostate cancer.

Narayanan

Dear Olena

No matter what any academy may say, PSA is still the most used screening method for prostate cancer, throughout the world and even in the US.

It is inexpensive, simple and non invasive.

Theory is nice but practice is a different issue.

You cant use ultrasound, CT scan or MRI nor the finger of the urologist as screening methods for prostate cancer.

In the old days it was the finger but tumors of less than 1 cm cant be detected this way.

Oh, yes Olena. PSA Screening for early detection of prostate cancer is not recommended in all population in general.

But the earlier reference/link you sent (https://www.researchgate.net/deref/https%3A%2F%2Fwww.auanet.org%2Fguidelines%2Fearly-detection-of-prostate-cancer-(2013-reviewed-and-validity-confirmed-2015) , from the American Urological Association, of 2015, which is later to the references sent now, strongly recommend PSA Screening in age group 55-69! With "with shared decision making" which in effect means that they will be prompted to accede to the test!

It all means that no one really knows what to do! Soon some medical drug company will manage to start treatment for these patients too based on raised PSA alone, yes, they will manage it. They will find some plausible excuse too.

As I remember, finsteride does decrease the future incidence of prostate cancer in such patients, ie those with BPH, but relative frequency of high grade cancers is raised.

Narayanan

In Argentina and Italy the health system covers PSA.

I have no statistical rates of survival in this countries.

Hungary government covers PSA as screening method in population above 60 y.o.

Health systems on USA may not cover it. But lets say that the USA has no real health system as we have in the EU.

Dear Olena

Evidence based medicine is a method for saving money. It is not a really integral and preventive medicine method.

The worst medical mistakes I have seen in 48 years of practice were under the evidenced based practice. When you get enough evidence is late for the patient.

The fundamentals of oncology practice are based on early diagnosis.

Best regards

Thank you for updating me with various aspect of cancer;

It is correct in most of the cases cancer is diagnosed quite later stage. It happens due to delay in collecting the exact evidence and almost no method for early cancer detection.

So here we would like to discuss to explore the feasible possibilities of early detections.

Some authors have reported the detection of breast cancer through protein over expression in saliva for early detection.

What is the feasibility and accuracy of detection through over express of saliva..

Dear Hariom Gupta

PET/CT Scans and Cancer Positron Emission Tomography (PET) and Computed Tomography (CT) imaging have become essential diagnostic tools physicians use to reveal the presence and severity of cancers. PET/CT imaging helps physicians detect cancer, evaluate the extent of disease, select the most appropriate treatments, determine if the therapy is working, and detect any recurrent tumors.

http://www.petscaninfo.com/zportal/portals/pat/cancer

Regards

Houda

The pathologica confirmation of the tumor is always required before startin any type of treatmentl

Dear Olena

It may not be resorting to a method due to high cost, which may not be covered by health insurance for several countries, So that the patient is not in a vicious cycle of diagnostic methods, let's assume, based on a simple chest X radiograph revealed a lung cancer, how will know that the starting point or is the emergence of cancer from a second area, and whether biopsy will confirm or deny, may be exile in the area of taking biopsy, I have an anatomically diagnosed case with 11 reports, each 3 it which is different

Best regards

Houda

In answer to your question -

Re early detection and screening - There are many modalities, including- Blood Tests, Tumour Markers, Imaging, Cytology, Pap smear, Endoscopy.

As Mohit Sharma has stated- "Any method or test should have sufficient sensitivity, specificity and positive predictive value..to be valid.. period"

Re best method for cancer diagnosis - this is a Histopathological diagnosis first,

- with tissue typing and genetic markers becoming increasingly more important in treatment decisions, to assess which of various treatment modalities would be most effective.

I fully agree with the opinion from Dr. N´Netto

The best thing would be to get new serologic makers in order to achieve an early diagnosis

Prof. Luis Rodrigo, you are Correct, It will be really good achievement if some one (including me and you also) identify more appropriate serologic marker for cancer. To identify appropriate marker of the same, we are doing effort by sharing idea and possibilities to conceptualize a good approach for the same.

I had initiated my discussion in the concern of MRI technique and MRI contrast based detection of small size cancer and understanding their invasive character. However all of you updated me with other concern and views of cancer diagnostic which really very good for me.

It is also correct that blood based detection will be more suitable for the early detection of cancer however the exact identification of cancer sites of very primary stage is also necessary need to fight against the cancer and effective treatment of cancer of early stage.

So, what is your views about detection of exact sites of early stage cancer ?

regards

It is possible that a large number of cells become cancerous, grow to certain sizes and then die away or killed. We may develop serologic or other tests which can identify even these cancers. And this will lead to the problem of differentiating between those which will die off and those which won't; whether to treat or not treat them, etc.

Too early a detection may become a bane, not a boon!

Narayanan

Prof . Narayanan Bhattathiri: You are correct that with serologic test can detect but for the treatment of identified cancer there is essential need to identify the exact affected region to better treatment and management. I think it can be appropriately address with cancer targeted drug and contrast agent (either CT or MRI).

Can you give your views and suggestion in the concern of cancer targeted MRI contrast agent for the exact detection of cancer sites of early stage ?

Is MRI based imaging (targeted contrast) method be better compare to other imaging technique such CT scan etc......

Dear Colleagues

In your opinion, how many times a cancer patient is followed up with these devices in the year and will be the cause of new cancers

Dear Joe Graymer

Thank you, A useful answer

Dear Hari Om

Diagnosis of cancer is still histological; treatment for cancer can be legally, as far as I know, be offered only if a certified pathologist report it as such. Except may be a few instances like PSA in Ca. Prostate, beta-HCG in Choriocarcinoma where tumour markers suffice. For pathology at least a cytological specimen is needed.

Tumours have tumour associated antigens, some of which are specific for some tumours. The detection of their presence is the basis of immunohistochemistry; but here too specimen is needed from the tumour tissue.

Sometimes these proteins can appear as tumour markers in the blood. There are around one hundred types of cancers and as far as I know there is no marker that can act as a single diagnostic marker for ALL cancers. Even in those where immunohistochemistry is done biopsy/cytology specimen is needed because their concentration in blood is not sufficient for detection with 100% sensitivity and specificity.

It is unlikely that there is a universal marker which will identify all possible cancers. This is because even normal tissues are of different tissue types.

Even if a marker is developed which can detect a specific cancer as small as 1mm, it will not be the final answer. Because treatment may not be necessary because such a tumour may never develop into life threatening dimensions.

You may think that follow up studies will be useful. Yes. But the problem is that while that particular marker is being followed up, the person may develop one among the other 99 cancers.

The above is applicable to scanning after administration of targeted agents. (I think you mean PET and SPECT scan; NOT MRI scan). These are used now for staging and follow up studies where histological diagnosis has been already done.

Same problem for early detection using saliva etc.

Narayanan

Early detection can ensure to remove precancerous lesions; however to wait for a symptom of cancer is to be seen then it is a well grown stage of cancer.

https://www.apollohospitals.com/departments/personalised-health-check/packages/cancer-screening-packages

Dear Krishnan

If early detection of cancer itself is a complicated issue, precancerous lesions are more do!

None of the tests given in Apollo package can be considered as"early detection" ones, except the PSA. They are Cancer Screening ones. Some of the detected cancermay be early, that is all. Apollo also don't claim to do any early detection.

Narayanan