Morbidity after Transperineal Permanent Seed Implantation (TPSI)
in 275 Patients with „Low Risk“ Prostate Cancer
Block,
T.1); Zimmermann, F.2); Czempiel, H.1)
1)Urologische Praxis und Medizinphysik Vaterstetten,
2)Klinik für Strahlentherapie und Radioonkologie, Technische Universität
München
Introduction:
This study evaluated morbidity after TPSI of “low risk” prostate cancer (cT1-2a Gleason Score <= 6 iPSA <10 ng/ml) according to the recommendations of ABS, ESTRO and EORTC.
Patients:
n = 275 (av. 66 . 5 ± 6. 9 years)
no patient underwent prior TUR-P
Median follow up: 26.8 (3.0 – 68.5) months
av. prostate volume: 34.5 ± 10.6 cc
av. seeds: 4 9. 3 ± 10 . 5 with av. 1 9. 3 ± 3 . 4 needles
Routine pre- and postoperative care:
alpha blockers, laxative, antibiotics, NSAP; discharge without transurethral catheter.
Short term toxicity I:
(<3 months)
Seed dislocation into the bladder because of consequent coverage of the baseline: 2.3 % (removed endoscopically and reinserted immediately)
Short term toxicity II:
(<3 months)
Modified RTOG toxicity scale
Grade 1: 9 0.2 % (irritation and/or obstruction) :
Grade 2: 4.2 % (urinary diversion 2-7 days)
Grade 3: 4.2 % ( suprapubic fistula >7 days)
Grade 4: 0.4% (urethral seed dislocation)
no grade 5 toxicity occured
Short term toxicity II:
Incontinence: 0%
Erectile disorder: 29.7 % (116/165 prior to TPSI potent patients remaied potent
(83 % of patients responded to „modern erectile drugs“)
Rectal complication: < 1% (diarrhea), no fistula
Ultrasound guided TPSI:
Prescription dose: 145 Gy
Modified peripheral loading
Online-Planing: D90 > 180 Gy, V100 > 99%
D1 urethra: <= 230 Gy
D10 anterior rectal wall: <= 145 Gy
Embedded 125Iodine Seeds 0.512-0.721 mCi („StrandTM“)
TPSI Dosimetry Software: VariSeed/PSID
International Prostate Symptom Score :
Perspective:
Realtime dose calculation is albe to evaluate quality of seedimplation during and immedately after the procedure.
Furthermore, urinary and rectal toxicity are monitored during TPSI. This procedure should decrease acute and late toxixity and might the start of standardized quality assurance.
Evaluation of toxicity:
(short and long term)
Modified RTOG GU toxicity scale
EORTC QLQ-C30 Questionaire
International Prostate Symptom Score
evaluated 4 weeks before and 3, 6 and 12 months after TPSI respectively
Comparision of grade 2 and 3 toxicity after TPSI (125J/103 Pd)
Author |
n |
Retention |
Locke (2002) |
62 |
34% |
Bucci (2002) |
238 |
15% |
Han (2001) |
160 |
32% |
Kang (2001) |
139 |
14% |
Gelblum (1999) |
600 |
43% |
presented study |
120 |
8% |
Realtime Dose Calculation:
Conclusion:
All patients suffered from lower urinary tract symptoms after TPSI. However, grade 2 and 3 toxicity occurred only in <10% of patients implanted. Toxicity can be influenced by medication of alpha blockers, anticholinergics and antibiotics sufficiently. No incontinence and no severe rectal complication were observed. The rate of erectile disorder is within the range literature reported. Nowadays, realtime dose calculation is a substantial tool to decrease toxicity and to stabilize quality assurrance of TPSI.
