GIC Protocol Meeting

Ca Stomach

Presentor-Dr Richa Madhawi

Moderator- Dr S. Pathy

Current Protocol

• Early - Surgery ± Postop CTRT• Indications Stage II onwards

– (Margin positive, Gross residual disease ,Transmural infiltration Regional LN +)

• Locally Advanced - • Resectable: Surgery + Postop CTRT • Adjuvant CTRT - 45Gy/25#/5wks to tumor bed and r regional lymph nodes + MacDonalds Protocol

Unresectable :Neoadjuvant chemotherapy 3 cycles f/b assessment for surgery

Current protocol

• Metastatic /Palliative

Symptom based management• Pall RT30Gy/10#/2wks (rarely used)• Pall Chemotherapy5FUFA / capecitabine+ CDDP• Surgery feeding procedure/ gastric bypass surgery• Best supportive care

Radiation Therapy Technique

Target Volume • Gastric or tumor bed• Anastomosis and gastric remnant• Nodal chains (lesser and greater curvature, celiac axis,

pancreatodeodenal, splenic, porta hepatis and in some cases upto para aortic nodes upto L 3 )

Treatment Planning

Radiation Therapy Technique

Proximal /Cardia/GE junc

• 3-5 cm margin to distal esophagus, medial left hemidiaphragm & adjacent pancreatic body.

• Nodal areas at risk : adjacent paraoesophageal, perigastric, suprapancreatic and celiac lymph nodes.

Middle / Body

• Body of the pancreas.• Nodal areas at risk : Perigastric, suprapancreatic, celiac, splenic, hilar, porta hepatic

and pancreaticoduodenal lymph nodes.

• Distal/Antrum

• Head of pancreas,3-5 cm margin of duodenal stump (if lesion extended to gastroduodenal junction)

• Nodal area at risk : Perigastric, suprapancreatic, celiac, splenic, hilar, porta hepatic and pancreaticoduodenal lymph nodes.

L. Gunderson, Henry Sosin ,IJROBP ,Volume 19, Issue 6, December 1990, Pages 1357–1362

Radiotherapy Technique

Radiation therapy technique

3D-CRT

OAR(Organ at risk)

• Kidney• B/L whole kidney Dmean <15-18 Gy• V20 < 32%• Liver -GTV Dmean < 30-32 Gy

• Spinal Cord Dmax 45 Gy• Heart Dmean <26 Gy V30 46%(pericardium)

QUANTEC guidelines followed for DVH evaluation

Quantitative Analysis of Normal Tissue Effects in the clinic,IJROBP,2010 Mar;1;76

Treatment Strategies with clinical evidence Early gastric cancer

Study Treatment Schedule

LRF MS OS

SWOG-INT0116 Sx→CTRTSx

19%29%

36 months27 months

50%41%

Postop chemoradiation is standard of care

• CRITICS Trial (Dutch) – NACT→ Sx (D1 resection)→ CTRT vs CT alone (ongoing RCT)

Treatment Strategies with clinical evidence locally advanced gastric cancer

Resectable

Validation of result needs to be determined in large prospective RCT

Study Treatment schedule pCR R0 resection 3 yr survival

POET Trial NACT→SxNACT+ RT→Sx

2%16%

37%64%

28%47%

Shahl et al NACT →Sx vs NACT→CTRT→SX

2.0%15.6%

27.7%47.4%

RTOG 9904 NACT→CTRT→Sx

26% 77%

Treatment Strategies with clinical evidence locally advanced gastric cancer

• Unresectable/Inoperable

• Pt with incomplete resection /+ ve margin are also appropriately managed by CTRT

• Pt assessed preoperative for unresectable with (-) margin preop CTRT can preclude gross tumor excision

Group Treatment arm

EBRT schedule Number Survival Survival 5 yr

Mayo Clinic EBRT± 5 FU 40 Gy/20# 48 13 vs 5.9 month

12% vs 0

GITSG CT± EBRT 50 Gy/8 wk - split 90 18% vs 7%

Radiotherapy dose

• Dose of Radiation

45 Gy/1.8 Gy per fraction/ 25 # f/b 5.4 - 9 Gy/3-5 # in margin +ve / residual disease

• Impoved locoregional control with dose escalation in adjuvant setting.

Henning GT, IJROBP,2000

Proposed Recommendation

• RT Dose 45Gy/25Fractions/5weeks weeks ± boost 5.4- 9Gy for margin positive and residual disease)

• Neoadjuvant CTRT in locally advanced operable gastric cancer in research setting/pilot study