Key points of this article:
- An elevated PSA after radical prostatectomy suggests a residual prostate cancer lesion. If the serum PSA level exceeds 0.2 ng/mL on 2 consecutive occasions, it indicates biochemical recurrence of prostate cancer.
- After a diagnosis of biochemical recurrence is made, the doctor will continue to evaluate fully for tumor recurrence, which is not the same as tumor recurrence.
- If a tumor recurrence is definite, it is important to continue to determine if it is just a local recurrence or if there are lymph node metastases or distant metastases. This information helps guide treatment planning and timing.
Patients with prostate cancer are monitored for prostate-specific antigen (PSA) levels after curative treatment (surgery or radiation), and PSA generally decreases for some time after treatment. However, if the PSA rises again, the patient will be very anxious: what does it mean? Does it mean that the cancer has come back? How can I tell if my condition is serious? How do I treat it after a recurrence?
In this case, the doctor will first clarify whether it is a cancer recurrence and then check whether the cancer is still confined to the prostate area, because these are about treatment decisions and the timing of treatment.
1. What does an elevated PSA mean?
Post-surgical PSA elevation
The PSA should be undetectable 6 weeks after a successful radical prostatectomy, but if the PSA is still elevated, there is still PSA-producing tissue in the body, which is a residual prostate cancer site.
After radical prostatectomy, because there is a clearance period for residual PSA in the blood, it is best to recheck PSA 6 weeks to 3 months after surgery, and the current national standard is that 2 consecutive serum PSA levels above 0.2 ng/mL indicate biochemical recurrence of prostate cancer.
Post-radiation PSA elevation
The PSA level decreases slowly after radiotherapy because the prostate is still present, and may not even reach its lowest value until more than 3 years after radiotherapy. The slower the PSA decreases after radiation therapy, the less malignant the prostate cancer and the better the prognosis; conversely, a rapid decrease in PSA may not be a good thing.
The lowest PSA value after radiation therapy is a marker of biochemical cure and an important prognostic factor, and in general, the lower the value, the higher the cure rate, and generally the prognosis is better for those with a minimum PSA level of 0.5 ng/mL within 3 to 5 years.
The current national standard is that a PSA level of 2 ng/mL or more above the PSA minimum after radiotherapy (with or without concomitant endocrine therapy) is considered a biochemical recurrence of prostate cancer.
2. Is a re-elevation of PSA a recurrence of cancer?
.
When the PSA is elevated again after surgery, it is important not to be pessimistic that the last treatment has failed, but to monitor the serum PSA value every 3 to 6 months to monitor the trend of PSA to determine if the cancer has returned.
If the elevated PSA is indeed due to residual cancer or recurrence, i.e., clinical recurrence, the next step is to determine whether there is local recurrence, regional lymph node metastasis, or distant metastasis.
3. How do you determine prostate cancer recurrence?
.
If the PSA is elevated, your doctor will usually determine if the prostate cancer has returned in the following way:
- Rectal examination Local recurrence should be suspected if there are new nodules in the prostate area after curative treatment.
- Transrectal ultrasound is recommended for biopsy of the prostatic fossa in cases of localized hypoechoic lesions.
- Transrectal ultrasound prostate biopsy provides histologic evidence of local recurrence, typically with a PSA greater than 0.5 ng/mL after radical surgery.
- Imaging and nuclear medicine A whole-body bone scan with abdominal CT, MRI, or PET/CT can detect local recurrence and distant metastatic lesions. Tests such as bone scans can be performed in patients with skeletal symptoms, or in patients with PSA levels greater than 20 ng/mL, PSA doubling time less than 6 months, or PSA elevation rate greater than 0.5 ng/mL/month.
Currently, the internationally agreed standard for postoperative biochemical recurrence is a PSA of less than 0.2 ng/mL on 2 consecutive occasions after surgery. Patients with biochemical recurrence are thoroughly evaluated by their physicians to confirm whether clinical recurrence has occurred and whether there is local recurrence, regional lymph node metastasis, or distant metastasis. Approximately 50% of patients with biochemical relapse have local recurrence, and the remainder have either distant metastases or a combination of both local recurrence and distant metastases.
Many patients are very concerned about why they were diagnosed with relapse and would like a detailed explanation from their doctor. I should tell you that the knowledge is very specialized and can be difficult for patients without a medical background to explain. To help some patients who want to understand this part of the story, please refer to the table below.
Reference indicators for determining postoperative recurrence
| Post-operative local recurrence is more than 80% | Postoperative likelihood of distant metastases exceeds 80% | |
| PSA | PSA rise after 3 years post-operatively; | PSA rise within 1 year of surgery; |
|
PSADT* |
Greater than 11 months; | 4 to 6 months; |
| Gleason score | No greater than 6 points; | 8 to 10 points; |
| Pathological staging | below pT3apN0, pTxR1 (R1 implies positive surgical margins). | Pathological staging of pT3a, pTxpN1. |
*PSADT: prostate-specific antigen doubling time
4. How should recurrence after radical prostatectomy be treated?
.
Treatment options after recurrence vary for patients with different conditions:
- For local recurrence: start salvage radiotherapy as early as possible, in principle when the PSA is less than 1 ng/mL and the PSA doubling time is short.
- Distant metastases: early endocrine therapy, which may also delay progression to clinical metastases. For patients with a Gleason score less than 7, PSA recurrence more than 2 years after surgery, and PSADT greater than 10 months, watchful waiting, in which the patient is observed for definite metastases before treatment, is also a very viable treatment option. Because such patients generally have slow disease progression, the median time from biochemical recurrence to the development of clinical metastases is 8 years, and the median time from the development of metastases to death is 5 years.