Encore: Revision: PSA accuracy in bone metastases: Before treatment

[Admin]

This is why you trust your doctor, and not a bunch of amateurs like ourselves:

I made a mistake in summarising the abstract below.

More careful reading of the abstract makes it clear that this study looked at men before treatment, without symptoms of bone metastases.

 

You can see the correction (with colour and layout) at:

http://tinyurl.com/k5ww8xb

 

Or roughly below:

 

 

Jim Marshall (not a doctor) said ...

In brief, what a bone scan will likely find before you have any kind of treatment for prostate cancer:

PSA greater than 100

Prostate cancer very likely has spread to several places in your bones. (multiple metastases)

 

PSA greater than 20

Likely prostate cancer has spread to at least one place in your bones.

 

PSA less than 20

Quite unlikely prostate cancer has spread to your bones.

 

The PSA blood test is getting bad press lately. There have been calls to limit its use.

 

This paper is not about PSA levels after treatment. The paper below confirms the usefulness of PSA in telling whether prostate cancer may have spread to your bones before you are treated.

 

It reports on the most commonly used 'bone scan' (a radionuclide bone scan) where you are injected with short-life radioactivity, and then scanned to see where it sits. The radioactivity prefers bone damage, especially prostate cancer bone damage. 

 

The men had no symptoms of bone metastases (e.g. pain), and no previous treatment for prostate cancer.

 

... end Jim

Indian J Nucl Med. 2012 Apr-Jun; 27(2): 81–84.

doi:  10.4103/0972-3919.110683

PMCID: PMC3665151

Predictive value of serum prostate specific antigen in detecting bone metastasis in prostate cancer patients using bone scintigraphy

 

Koramadai Karuppusamy Kamaleshwaran, Bhagwant Rai Mittal, Chidambaram Natrajan Balasubramanian Harisankar, Anish Bhattacharya, Shrawan Kumar Singh,1 and Arup K Mandal1

Department of Nuclear Medicine, Post Graduate Institute of Medical Education and Research, Chandigarh, India

1Department of Urology, Post Graduate Institute of Medical Education and Research, Chandigarh, India

Address for correspondence: Dr. Bhagwant Rai Mittal, Department of Nuclear Medicine, PGIMER, Chandigarh - 160 012, India. E-mail: brmittal@yahoo.com

Copyright : © Indian Journal of Nuclear Medicine

This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Introduction:

 

Radionuclide bone scan (BS) used to be the investigation of choice for detecting osseous metastases in prostate cancer. Now, with the availability serum prostate specific antigen (PSA) testing, clinicians do have a timely, cost-effective method to determine those patients who are highly unlikely to have osseous metastases. We determine the utility of PSA for predicting the presence of skeletal metastasis on BSs in prostate cancer patients.

 

Materials and Methods:

 

Retrospective analysis of medical records of 322 consecutive prostate cancers patients subjected to BS during the last 3 years was done. 52 cases were excluded due to following reasons: Serum PSA not available, hormonal or other therapy given prior to serum PSA measurement, and/or BS, and symptomatic for bone metastasis. In remaining 270 cases, PSA value and BS were evaluated. BS was performed with Tc99m methylene diphosphonate (MDP) as per the standard protocol.

 

Results:

 

BS was found to be positive in 153/270 (56%) and negative in 117 (46%) patients. Of the 153 positive cases, 108 (70%) had serum PSA > 100 ng/ml, 42 (28%) had PSA of 20-100 ng/ml and only 3 (2%) had PSA < 20 ng/ml. All the patients with PSA > 100 ng/ml had multiple skeletal metastasis. Of the 117 negative cases, 110 (94%) had a PSA < 20 ng/ml, 5 had between 20 and 100 ng/ml and only 2 (1.8%) had PSA > 100 ng/ml. Of the 113 patients with serum PSA < 20 ng/ml, 110 (97.4%) did not show any bony metastasis. 150/157 (95.5%) patients with PSA > 20 ng/ml had bone metastasis. Using this criterion, 110 (40.7%) scans would have been omitted.

 

Conclusions:

 

Serum PSA < 20 ng/ml have high predictive value in ruling out skeletal metastasis. Our data are in corroboration with results from previous studies that BS should be performed only if PSA > 20 ng/ml. Using this cut-off, unnecessary investigation can be avoided. Avoiding BS in this group of patients would translate into a significant cost-saving and reduction in their psychological and physical burden.

 

Keywords: Bone scan, prostate Ca, prostate specific antigen, Tc99m-methylene diphosphonate

This extract is in the public domain.

 

Any highlighting (except the title) is not by the author, but by Jim Marshall.

Jim is not a doctor.

[Geoff Buttfield]

Mine was PSA 50, but no mets (so far )

[Paul Edwards]

I certainly fell within the 95.5% category - PSA 30.1 with a single bony metastasis.

 

Whilst there will be men with PSA > 20 ng/ml who don't have bone metastasis and men like Eamon and Brian with low PSA who have bone metastasis, it would be interesting to see whether you would get the same results as this study with a larger number of patients in Australia.