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Toronto,
ON— Outcomes for patients with esophageal cancer are poor,
with only a 30 to 40 per cent cure rate for select patients who
undergo surgery. However, recent trials using preoperative RTCT
and preoperative CT are promising strategies to improve survival,
said Rebecca Wong, MB, ChB, MSc, Radiation Oncologist, Princess
Margaret Hospital, Toronto.
Dr. Wong and colleagues are conducting a Phase II trial to assess
the efficacy of preoperative CPT11/cisplatin combined with external
beam/
brachytherapy for potentially resectable thoracic esophageal cancer.
“In practice, where patients have suspicious nodal involvement
and bulky disease, this is the group where we would especially consider
giving preoperative radiotherapy and chemotherapy at this time,”
Dr. Wong said.
Previous data
She cited a randomized trial by Walsh et al (NEJM 1996;335:462-467)
showing that patients with nodal involvement benefit from preoperative
CTRT. The trial found a three-year survival of 32 per cent with
preoperative 5-FU/cisplatin, compared with a six per cent survival
with surgery alone. In contrast to seven negative trials that have
been done in this area, all patients in this trial had adenocarcinoma
and more than 80 per cent had positive nodal involvement.
A randomized study by the Medical Research Council in the United
Kingdom (Lancet 2002;359:1727-33) showed a median survival
benefit of three months using cisplatin-based CT. However, a randomized
trial by Kelsen et al showed no benefit. (N Eng J Med 1998;339:1979-1984)
“There is speculation as to why the MRC study was positive,”
Dr. Wong said. “Perhaps the chemo is just about right, whereas
the Kelsen study wasmore aggressive, and the long-term
toxicity and morbidity would outweigh the benefit.”
A published individual patient data meta-analysis for preoperative
RT and surgery showed a trend (not statistically significant) toward
survival benefit. The estimate for the degree of benefit is in the
order of five per cent, she said.
Previous trials using postoperative RT and surgery have shown that
some patients have done worse with this therapy. However, large
fractions, three times a week were delivered in these trials, which
would not be used today, Dr. Wong said.
“If you look at the local recurrence rate, it’s actually
lower in the combined modality, and this with a large dose of radiotherapy.
“It raises the question whether postoperative radiotherapy
could reduce local recurrence rates, especially in patients who
have positive margins.”
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