Table 3.
Studies reporting IMRT and 3D-CRT toxicities in pancreatic cancer
| Study | Nature of study and number of patients | Dose/fractionation | Concurrent chemotherapy | Outcomes | Acute toxicity (≥ Grade 3) | Late toxicity (≥ Grade 3) |
|---|---|---|---|---|---|---|
| Abelson et al., 2012 (20) | Retrospective, 47 (IMRT; 29 adjuvant, 18 definitive) | 50.4 Gy/28 fractions for adjuvant cases; 54 Gy/30 fractions for definitive cases | Capecitabine /5-FU | 1-year FFLP: 92%; 2-year FFLP: 80%; 1-year OS: 79%; 2-year OS: 40% | Biliary stent blockage [1], cholangitis [1], small bowel obstruction [1], enteritis (1, died) | Small bowel obstruction [1], biliary stricture [2], common bile duct perforation [1] |
| Colbert et al., 2017 (21) | Retrospective, 154 (59 IMRT, 95 3D-CRT) | For 3D-CRT: 50.4 Gy/28 fractions | Gemcitabine/5-FU/cetuximab | IMRT group (dose escalation): anorexia [2]; rate of acute Grade 3 toxicities were lower in IMRT (dose-escalated) than 3D-CRT (standard dose): 4% vs. 16% (P=0.004) | IMRT group (dose escalation): duodenal/esophageal strictures [2], GI bleeding [4] | |
| For IMRT: all had BED >70 Gy (63 Gy/28 fractions, 67.5 Gy/15 fractions, 70 Gy/28 fractions) | ||||||
| Krishnan et al., 2016 (22) | Retrospective, 200 (all LAPC); Dose escalation group: 41 IMRT, 5 3D-CRT with IMRT boost, 1 IMRT with proton therapy boost); Standard dose group: 13 IMRT, 140 3D-CRT) | Standard dose group: 50.4 Gy/28 fractions or 50 Gy/25 fractions | Capecitabine/5-FU | Median FFLP: 7.3 months; Median OS: 15.3 months; 1-year OS: 60%; 2-year OS: 22%; | Dose-escalated group: Diarrhoea [1], GI bleeding [1] | |
| Dose-escalated group: 57.25 Gy in 25 fractions | Those with BED >70 Gy had improved outcomes than those with BED ≤70 Gy | |||||
| Prasad et al., 2016 (23) | Retrospective, 205 (134 IMRT, 71 3D-CRT) | 50.4 Gy/28 fractions; IMRT cases: simultaneous boost to gross disease to 56 Gy | Gemcitabine +/− 5-FU/capecitabine | 3D-CRT: Diarrhoea [2], Nausea [3]; IMRT: Diarrhoea [3] | ||
| Yovino et al., 2011 (24) | Retrospective, 46 IMRT cases; toxicities compared to toxicity data from 100 patients from RTOG97-04 (3D-CRT) | 50.4 Gy/28 fractions | Capecitabine/5-FU | Median PFS: 17.5 months; Median OS: 24.8 months (resectable); 9.7 months (unresectable) | IMRT: Diarrhoea [2], anorexia [2]; 3D-CRT (RTOG97-04): Diarrhoea [78], nausea/vomiting [49], anorexia [9] | IMRT: small bowel obstruction [2] |
IMRT, intensity modulated radiation therapy; SBRT, stereotactic body radiotherapy; LAPC, locally advanced pancreatic cancer; OS, overall survival; GI, gastrointestinal; PFS, progression-free survival; BED, biological equivalent dose; FFLP, freedom from local progression; 3D-CRT, 3D conformal radiation technique.