A Randomised Study of Consolidation CTRT Versus Observation After First Line Chemotherapy in Advanced Gallbladder Cancer: RACE-GB Study

Treatment:

Chemotherapy followed by Chemo-radiotherapy:

Patients in experimental arm will be administered 6 cycles of gemcitabine 1000 mg/m2 d 1+8 and cisplatin 25mg/m2 d 1+8 repeated 3 weekly followed by abdominal radiotherapy using a standardized 3 dimensional conformal radiotherapy (3DCRT) technique on a linear accelerator operating at beam energy of >= 6MV.The total target dose of RT will be 45Gy in 25 fractions of 1.8 Gy to GBC and lymphatics (GBC, liver infiltration, periportal coeliac, superior mesenteric and paraortic lymphnodes till L2) followed by a boost of 9 Gy to the GBC. GBC mass alongwith liver infiltration would be GTV, and a 5mm margin around it would be GB_CTV. Nodal CTV would be delineated after combining PV, CA, SMA and aortic nodes. A Boolean of GB_CTV and Nodal CTV would be Final CTV. PTV margin would be 1 cm around Final CTV. DVH constraints would be : mean liver dose<30 Gy (liver would be delineated after subtracting GB_CTV), mean kidney dose <18 Gy (combining both kidneys). Other OAR to be delineated: stomach, bowel and their doses to be noted. Concurrent capecitabine to be given @1250 mg/m2 (Monday to Friday). Weekly clinical ,haemogram, LFT assessments will be done during the treatment.

Toxicities documented during adjuvant therapy will be recorded using the CTCAE version 3.0 (NCI 2006 scale). Toxicities arising more than 90 days since the completion of radiation therapy and attributed to radiation will be assessed according to CTCAE criteria and counted as late radiation toxicities.

Observation : enrolled patients will be administered 6 cycles of gemcitabine 1000 mg/m2 d 1+8 and cisplatin 25mg/m2 d 1+8 repeated 3 weekly for 6 cycles and then kept on observation.