By Dr Elie HADDAD
Oncologist Radiotherapist – Center HARTMANN
Prostate cancer is the most common cancer in humans over 50 years old with 70,000 cases in France and 9,000 deaths a year.
After surgery, adjuvant or catch-up radiotherapy may be proposed.
Adjuvant radiotherapy corresponds to the principle treatment after surgery to prevent recurrence in the presence of risk factors.
Three international studies have demonstrated that adjuvant radiotherapy reduces the risk of recurrence at 5 years and 10 years; It is proposed in case of involvement of the seminal vesicles, if the capsule is exceeded, with surgical margin invaded or in case of pelvic lymph node involvement.
In the event of a rise in PSA after surgery, the goal of radiotherapy is to destroy persistent tumor cells in the operated area.
A primary condition of success is to start treatment as soon as possible, and for low PSA values of less than 1 ng it is unlikely that radiological examinations will return to the precise site of recurrence.
We then rely on predictive factors for local recidivism:
- A PSA that returns to 0 in postoperative before ascending
- A delay of more than one year before recurrence
- A slow kinetic
- Invasive surgical margin or T3.
The dose delivered is 66 Gy on a volume adapted to the histological result of the prostatectomy. It usually includes the surgical prostate bed +/- the ganglionic areas according to the dysfunction.
It is preferable to start the treatment once the continence has been acquired.
The side effects are minimal: frequent and imperious urination, anal irritation, risk of aggravation of incontinence in the order of 3%.
Conditions for successful remedial radiotherapy
When should radiation therapy be started after surgery?
In the event of a biological failure of prostatectomy, and possibly before the PSA level reaches 0.5 ng / ml, GUROC (Genito-Urinary Radiation Oncologists of Canada) recommends that remedial radiotherapy As early as possible.
ASTRO (American Society for Radiation Oncology) recommends starting it before the PSA is greater than 1.5 ng / ml.
In France, it is assumed that a PSA level of 0.2 ng / ml corresponds to the threshold at which a catch-up radiotherapy can be initiated.
Adjuvant radiotherapy or remedial radiotherapy?
A certain effectiveness of the postoperative systematic radiotherapy (“adjuvant”) was demonstrated: it increases the rates of survival without recurrence at 5 and 10 years and delays the appearance of metastases.
However, its side effects and the limited risk of failure of prostatectomy lead to the indication only to high risk patients. These include those with extracapsular extension, surgical section invaded, invasion of a seminal vesicle.
For the other patients, close monitoring is recommended and, as soon as PSA levels higher than 0.2 ng / ml appear, possible remedial radiotherapy, in particular according to the age of the patient, of all its Risks and its desideratas.
Radiotherapy remains the only curative treatment after failure of a prostatectomy.
It is only in case of new recurrence or for patients with worse prognosis that other treatments such as hormone therapy could be considered.
Some bibliographic elements:
Treatment options related to prostatectomy
Effectiveness of remedial radiotherapy
Conditions de réussites de la radiothérapie de rattrapage