Table 1.
Select clinical series to have applied MR guided radiation therapy to pancreatic cancer.
| Author | N Panc CA | RT Dose/description | Bowel Constraints Applied | Conclusions/Toxicities Reported/Clinical Outcomes | Citation |
|---|---|---|---|---|---|
| Bohoudi et al. (9) | 10 | 40 Gy in 5, max doses up to 50 Gy in 5, tumor + 5 mm margin |
Duodenum, Stomach, Small Bowel:
V33Gy < 1 cm3 V25Gy < 20 cm3 |
• Clinicians can review and adjust contours within 3 cm from the PTV, both feasible and safe • Faster treatment planning strategy is discussed |
(9) |
| Henke et al. (10) | 5/20 | 50 Gy in 5, goal of 95% coverage by 95% prescription dose, tumor + 5 mm margin |
Stomach Max: V33 ≤ 0.5 cm3
Duodenum Max: V35 ≤ 0.5 cm3 Small Bowel Max: V30 ≤ 0.5 cm3 Large Bowel Max: V35 ≤ 0.5 cm3 |
• SMART is clinically deliverable and safe • Very low rate of toxicity |
(10) |
| Rudra et al. (11) | 44 | 40-55 Gy in 25-28 fractions (n=13) 30-35 Gy in 5 fractions (n=6) 40-52 Gy in 5 fractions (n=16) 50-67.5 Gy in 10-15 fractions (n=9) |
Range of institutional constraints included in supplement | • High dose (BED10 > 70) had improved 2 year overall survival, 49% versus 30%, p = 0.03 • Freedom from local failure was 77% in the high dose versus 57% in the standard dose • Grade 3 GI toxicity in 3/44 patients, all in standard dose |
(11) |
| Chuong et al. (12) | 35 | 35-50 Gy in 5 fractions, gross nodes also treated. 120%-130% dosimetric hot spots were included, provided OAR constraints met. 20 patients treated with ENI to celiac, SMA, and SMV to same dose as tumor |
Duodenum, Stomach, Small Bowel:
V35 Gy < 0.5 cm3 V40 Gy < 0.03 cm3 Large Bowel: V38 < 0.5 cm3 V43 < 0.03 cm3 |
• Median treatment time 83 min (56–108) • Five patients underwent surgery, 1 CR, 2 NCR • 1 year local control was 87.8% • Median time to local progression 7.4 months • 1 year DMFS was 63.1% • 1 year PFS/median PFS 52.4%/7.9 months • Median OS was 9.8 months (from completion of RT) • Acute grade 3 toxicity 2.9%, Late grade 3 toxicity 2.9% |
(12) |
| Hall WA et al. (13) | 3/10 | Mostly recurrent PAC, previously treated with RT, patients were given 25-35 Gy in 5 fractions |
Stomach: Max dose of 34 Gy to 0.03 cm3
Duodenum: Max point dose of 34 Gy to 0.03 cm3, 33 Gy < 1 cm3, ideal-V20 < 20 cm3, V26.5 < 5 cm3 Small Bowel: Max point dose of 34 Gy to 0.03 cm3, ideal-V20 < 20 cm3, V26.5 < 5 cm3 Colon: Max dose less than 34 Gy to 0.03 cm3. |
• Feasibility was demonstrated for this cohort using 1.5 Tesla MR Linac • Quantitative MRI can be acquired during treatment without longer table times • Longer term follow up needed for clinical outcomes such as late toxicity, OS, and local control |
(13) |
| Hassanzadeh et al. (14) | 44 | 50 Gy in 5 fractions, goal of 95% coverage by 95% prescription dose |
Esophagus, Duodenum, Small Bowel, Stomach Large Bowel: V36<0.75 cm3 for MR Linac 0.5 cm3 |
• Late grade 3 GI toxicity was 4.6% • Median OS was 15.7 months • One year local control was 84.3% |
(14) |
PAC, pancreatic adenocarcinoma; n, number of pancreatic cases included; CR, complete response; NCR, near complete response; DMFS, distant metastases free survival; PFS, progression free survival; NR, not reported; SMA, superior mesenteric artery; SMV, superior mesenteric vein; OAR, organs at risk; GI, gastrointestinal.