Prostate Gland-CA Diagnostics with Choline-PET/CT
Third most commonly in the male world population occus the prostate carcinoma. With in males in Europa it is the most common tumour disease. In Germany this means: 31.500 new prostate carcinoma every year.
The frequency of the prostate carcinoma continously increased in Germany since the end of the 80ties. Amon other factors, this can be traced back to the longerlife expectancy and the more sensitive diagnostic possibilities.
An early diagnosis increases the chance of a successul treatment and thus becomes the key to a successful cure.
Diagnostics in our laboratory
The basic diagnostics and the screening are carried out through the determination of prostate specific antigens (PSA-level). The PSA is a Serine-Protease, which is only secreted by epithelium cells of the prostate gland, either by healthy or affected prostate tissues. The serum level increases with an advancing life span of men and simultaneously causes the prostate gland to grow.
The significance of 4 ng/ml in diagnostics currently is accepted and fixed for further clarification in form of a tissue extraction. With every fith man having a PSA-level higher than 4 ng/ml a carcinoma will be found in the tissue sample. Nonetheless, about 13 up to 20 percent of all men with PSA-levels in normal areas (2.5-4 ng/ml) feature clinical cognizable prostate carcinoma.
MRT with an endorectal coil
Prostate carcinoma diagnostics are not always unproblematic, particularly if a tissue extraction misses the actual position of smaller tumour focuses. A significant improvement in diagnostics is the Magnet Ressonance Tomography (MRT) with endorectal coil (possible here).
In aftercare/relapse diagnostics of a prostate carcinoma, sensitivity and specificity of previous methods must be rated as insufficent, as a biochemical ascertainable relapse often predates months up to years compared to a clinical ascertaintable one. Especially the distinction between a local relapse and a lymph node metastasis as reason for a abstemious increase of PSA have not been possible so far.
Thus, in this case, there is a clinical necessity of proceeding a precise diagnostic PET/CT imaging, which is capable of illustrating metabolic activity, is a promising attempt to develop a more sensitive diagnostic measure. Choline shows an increased accumulation of prostate carcinoma tissue. Through a combinated examination, called Choline-PET/CT, a fusion of the functional (molecular) imaging method of PET and the anatomic precise imaging mehtods of Computer Tomography is made possible.
Functionality of Cholin-PET/CT
With the established PET/CT examination, a combination of the Positron-Emission-Tomography and Computer-Tomography, a radioactively marked sugar is used as tracer, as it is particularly effective in accumulating metabolicely active tumpour tissues.
Considering the prostate carcinoma, however, it is not always the case. The cells of the prostate carcinoma increasingly build in choline, which can be illustrated and proved through PET, if it has been radioactively marked.
Our experience as well as generally published literature show the value set of the choline-PET/CT-examination in both risk assessment considering the staging-adapted therapies in staging as well as the re-staging method in relapse diagnostics. Furtheron, PET/CT enables the detected pathologic lymphatic nods to be embedded in the target volume planning of the radiotherapy.
The former shown image shows from top to botton the illustrations of the CT and PET examinations, beneath this the fusionated pictures. The exact fusion of these pictures, as it is only possible, if both pictures were taken by the same piece of equipment, is one of the great advantages of combinated PET/CT examination.
A further advantage of the PET/CT combination is the ability to detect even wide-spread matastases, as this is a whole body examination.
The picture below shows a primary tumour in axial cut in the right prostate gland with skeletal metastasis in coccyx and pubic bone on both sides.
Choline-PET/CT in therapy planning
The permanent Brachytherapy of the locally limited prostate carcinoma is a therapy option equivalent to the radical prostate operation. In this case the Choline-PET/CT helps to illustrate possible tumour-supicious areals in the prostate internal and further treat them more succsessfully. In doing so, not only the primary tumour can be visualized. It is allows the visualisation of the extent of regional lymph node metastastasis.
The Choline-PET/CT examination
The Choline-PET/CT is completely incomplex procedure for the patient. The radioactively marked choline is injected directly into the vein before the examination of the patient. As Choline is a matter of a natural product, which usually becomes absorbed through food or is synthesized thorugh the liver and the intestinal wall, it is absolutely unobjectionable, particularly as the dose applied is extremely low. Directly after the intra-venous injection of the Choline the exposures are carried out, which take about 15 minutes.
Advantages of a Choline-PET/CT
- Exact identification using PET, whether the primary tumour or the local relapse is existent
- Exact localisation using CT. Particularly important for further therapies
- Examination of the whole body, which may also detect other existing metastases
- Funcional diagnostics (PET) captures malignant events a long time before morphologic (CT) changes occurk (PET) erfasst malignes Geschehen lange bevor es zu morphologischen (CT) Veränderungen kommt.
- Non-invasive diagnostic
Through brachytherapy using a hollow needle rice grain sized radioactive sources are implanted into the prostate gland, which destroy the tumour. In doing so, the circumfluent tissues are treated with care. Thus only in a few cases incontinence or impotence occurs, which usually are the most occuring side-effects of prostate gland operations.