Keywords:
Gastrointestinal tract, MR, Radiation therapy / Oncology, Cancer, Other
Authors:
S. C. Fong, E. Lau, D. Liu, N. Tebbutt, R. Khor, F. Wightman, S. Fisher, D. Williams, S. P. Ng
DOI:
10.26044/ranzcr2023/C-201
Results
Of the 16 patients who underwent surgical resection:
- Demographics: 13 males and 3 females with a median age of 73 years (range: 51 - 83).
- Diagnosis:
- Mid oesophageal adenosquamous carcinoma: 1 patient.
- Distal oesophageal/gastroesophageal: 8 patients (7 adenocarcinoma, 1 squamous cell carcinoma).
- Gastric adenocarcinoma: 7 patients.
- Clinical Stages:
- Stage 1: 7 patients
- Stage 2: 7 patients
- Stage 4a: 2 patients
- Treatment:
- Surgery alone: 8 patients (50%)
- Neoadjuvant treatment followed by surgery: 8 patients (50%)
Pathological correlation was found in 10 patients, while 4 showed downstaging post neoadjuvant therapy. Interestingly, 2 patients with higher pathological stages had nodal diseases that were undetectable on MRI, CT, and PET scans.
Among those who underwent surgery alone, 3 patients (38%) had MR-visible disease not detectable on CT but visible on PET.
In the neoadjuvant chemotherapy, all 6 patients had residual disease. MRI detected it in 3 patients exclusively, with 67% sensitivity (DWI and ADC mapping were useful). In comparison, CT had a sensitivity rate of 33%.
Post-neoadjuvant chemoradiotherapy, 2 patients had no MR-visible tumours, correlating with complete pathological responses.
Sensitivity rates based on pathological stage:
- MRI: 50% for stage 1; 33% for stage 2; 100% for stages 3 and 4A.
- CT: 25% for stage 1; 33% for stage 2; 0% for stage 3; 100% for stage 4.
- PET: 67% for stage 1; 33% for stage 2; 0% for stage 3; 100% for stage 4.