learning curve along 8 years of exprience prostate brachytherapy low-dose seeds

Learning curve impact from 8 years of experience in low-dose

brachytherapy for prostate cancer

Servicio de Radiofísica y PRInstituto Oncológico

Juan-Senabre XJ, Pérez M, Sánchez AL, López-Tarjuelo J, Santos-Serra A, Conde AJ, Beltran J, Ferrer C.

Purpose

Purpose

Dr. Mateo Pérez, urologist

I believe is feasible to analyzechart data patients to find out

learning curve results

Go ahead

What’s the learning curve?

Tm = T1 m(log2 L)

T1: time 1st PPBTm: time mth PPBL = learning rate

Go ahead

Is it applicable for this study?

PP

B t

ime

exec

uti

on

#PPB

D90

, V10

0

#PPB

Patients & methodsKruskall-Wallis test

144 Gy PD

(100, 108) Gy PD

Patients & methods

• Toshiba, Hitachi TRUS acquisition• Track-stepper software control• SPOT Pro TPS (Nucletron/Elekta)• 125-I Nucletron seeds (Isotron)• SeedSelectron automatic delivery system• #Med. Phys.: 4• #Rad. Oncol.: 3• #Urol.: 2

Interobserver dispersion?

Results. Time procedure

Results. Time procedure

n = 220, 11% rejectedL = 85.7% learning rate

Results. Nomogram

Results. DVH

Conclusions

Significant statistical results:• Time procedure• D90, V100• RV100

Consistent results:• Nomogram• #seeds, #needles• CN, DHI