The plan of favorable risk prostate cancer with RTOG 0415 dose constraint without MLC

 

Dose constraint for favorable risk prostate cancer by RTOG (Minimum PTV prescription; 3D-CRT or IMRT: 73.8 Gy in 41 fractions) is shown bellow. In RTOG 0415, eligible case is Gleason Score =< 6 and PSA < 10ng/mL. I made sample plan which almost cleared these dose constraints with conventional 7 ports irradiation without MLC.

 

RTOG 0415

A PHASE III RANDOMIZED STUDY OF HYPOFRACTIONATED 3D-CRT/IMRT VERSUS CONVENTIONALLY FRACTIONATED 3D-CRT/IMRT IN PATIENTS WITH FAVORABLE-RISK PROSTATE CANCER

 

Normal organ No more than  No more than No more than No more than

limit            15% volume     25% volume   35% volume    50% volume

                  receives dose  receives dose receives dose receives dose

                  that exceeds   that exceeds  that exceeds  that exceeds

Bladder                                                                             

Constraint          80 Gy            75 Gy          70 Gy          65 Gy

This case          77.2 Gy           74.4 Gy       69.4 Gy        59.4 Gy

Rectum                                                                             

Constraint          75 Gy            70 Gy          65 Gy          60 Gy

This case          73.1 Gy           66.4 Gy       59.9 Gy        49.4 Gy

 

Penile Bulb Mean dose less than or equal to 52.5 Gy

This case 51.54 Gy

 

Dose Goal         Minimum PTV     Minimum CTV     Maximum

(Prescription)          dose                 dose               dose to PTV

                  (encompassing    (encompassing           

                  >=98% of PTV)     >=100% of                

                                      CTV)                  

                  73.8 Gy             73.8 Gy            79 Gy

This case      73.85 Gy->98.04%      100%         79.92 Gy

1 The maximum dose must not be within an °»Organ at Risk°… such as the Rectum, Bladder, or Penile Bulb

GTV = Prostate CTV : Prostate PTV = CTV + 0.4-1.0 cm

(This case is ' PTV = CTV + 0.8 cm)

 

Please see MLC version of same case

The plan of favorable risk prostate cancer with RTOG 0415 dose constraint

Sample plan with IMRT as reference

Normal organ No more than  No more than No more than No more than

limit            15% volume     25% volume   35% volume    50% volume

                  receives dose  receives dose receives dose receives dose

                  that exceeds   that exceeds  that exceeds  that exceeds

Bladder                                                                             

Constraint          80 Gy            75 Gy          70 Gy          65 Gy

IMRT plan         76.2 Gy          74.7 Gy        72.8 Gy       67.5 Gy

Rectum                                                                             

Constraint          75 Gy            70 Gy          65 Gy          60 Gy

IMRT plan         76.4 Gy          71.0 Gy        63.8 Gy       52.3 Gy 

Penile Bulb Mean dose less than or equal to 52.5 Gy

This case 49.5 Gy

 

Dose Goal         Minimum PTV     Minimum CTV     Maximum

(Prescription)          dose                 dose               dose to PTV

                  (encompassing    (encompassing           

                  >=98% of PTV)     >=100% of                

                                      CTV)                  

                  73.8 Gy             73.8 Gy            79 Gy

This case      73.8 Gy->99%      100%         80.64 Gy

 

last modification date: 2007/07/04