10
Reassessment should be performed after completion of neoad-
juvant CRT to evaluate response and surgery is 4–6 weeks after
completion of RT. In the CROSS study, 92% of patients had R
resection (corresponds to resection for cure or complete resection
with negative margins) after neoadjuvant CRT and the rate of
pathological complete remission was 29%. Pathological complete
remission after neoadjuvant predicts for better survival.
As the main purpose of neoadjuvant treatment is for down-
staging of disease, only gross tumor and enlarged lymph nodes
need to be included in RT. The proximal margin in the CROSS
study was 4 cm and distal margin was 3 cm in case of tumor exten-
sion into stomach. Prophylactic lymphatic radiation to celiac axis is
not necessary as subsequent nodal dissection will be performed in
esophagectomy. The extent of tumor coverage may be less com-
pared with definitive RT as it is important to preserve adequate
organ function to allow for subsequent surgery. In addition, as the
stomach will be used for reconstruction as conduit after esopha-
gectomy, radiation to the fundus and body of stomach should be
limited, otherwise healing of anastomosis or viability of the gastric
conduit may be compromised in subsequent surgery.The RTOG 8501 is a randomized study that compared CRT versus
RT alone [ 6 ]. For CRT, the RT dose was 50 Gy in 25 fractions in
combination with cisplatin and 5-fluorouracil. The RT alone arm
received 64 Gy. Five years survival was 27% with CRT versus none
for those treated with RT alone. Local control was better with CRT
(27% persistent disease and an additional 16% local recurrence com-
pared with 40% and 24%, respectively, in RT alone arm, p < 0.01).
Distant failures were also reduced with CRT (22% vs 38%, p < 0.005).
This study established CRT as the standard of care for nonsurgical
treatment of esophageal cancer (see Note 2). The Intergroup 0123
study compared 64.8 Gy to 50.4 Gy, both with concurrent cisplatin
and 5FU. There was no significant difference in median survival
(13 months vs 18.1 months), 2-year survival (31% vs 40%), or
locoregional control (56 % vs 52 %) between the high-dose and stan-
dard-dose arm. Toxicity was increased in high-dose arm (11 vs 2
treatment-related death, respectively). Thus, 50 Gy remains as the
standard of care in concurrent chemoradiotherapy. If chemotherapy
is contraindicated, the dose to the primary cancer could be increased
to 60 Gy with reduced margins. With intensity modified radiother-
apy (IMRT), simultaneous boost to primary can be considered, e.g.,
55 Gy in 25 fractions. Prophylactic irradiation to celiac nodal regions
should be planned in definitive RT for tumor that involves the
esophagogastric junction.Postoperative RT is indicated in case of close or involved margin.
Extended volume of RT including the anastomosis as well as the
tumor bed was shown to reduce anastomotic relapse and locore-2.2 Definitive
Chemoradiotherapy
2.3 Postoperative
Adjuvant
Chemoradiotherapy
Dora L. W. Kwong and K. O. Lam