SAN FRANCISCO-Patients who are unfit or unwilling to undergo conventional treatment for early stage esophageal cancer appear to get curative relief by having the lesions frozen to death (Abstract 83).
In patients with T1a esophageal cancer, Franklin Tsai, MD, Assistant Professor of Medicine at the Scripps Clinic, La Jolla, Calif., said complete responses were observed in 74.4 percent of patients.
He and his colleagues also reported that, in all T1 disease patients, the complete response rate was 65.3 percent. But, he said, when the disease has reached state T2, the efficacy fell off sharply. He reported just 6.7 percent of the T2 patients achieved a complete response to the cold therapy.
"This study suggests that endoscopic spray cryotherapy is safe, well-tolerated, and effective for early esophageal cancer in patients who are not candidates for conventional therapy," Tsai said. "Because this is a relatively new technology, we selected patients who were not candidates for conventional chemotherapy or surgery," Tsai told Oncology Times. "Having said that, some of these data are now maturing so that we could be considering this treatment as first-line therapy in very early disease."
He said the results he observed are comparable to other technologies, but it is difficult to compare the outcomes because these patients were not suitable for other therapies. "These responses are more or less what I would expect," he said. "In early disease, the cryotherapy really does treat down to the submucosa. We deliver the cryotherapy directly onto the tumor.
"This is a registry study so I think it would be really interesting to have a group of patients treated with cryo and compared with conventional therapy alone," Tsai said. "There might be a role for cryotherapy as an adjunctive therapy. There is the idea that cryotherapy might sensitize the tumor so there might be better response to conventional therapy."
Although surgery is traditionally the standard of care for esophageal cancer, esophagectomy carries significant morbidity and mortality, he noted. "Alternative endoscopic therapies are needed for patients who are not candidates for conventional treatment," he said.
Cryotherapy in Action
In commenting on the study, Arvind Trindade, MD, Director of Endoscopy at Long Island Jewish Medical Center, and Assistant Professor of Medicine at Hofstra Northwell School of Medicine, said, "Cryotherapy is highly effective for early/superficial esophageal cancer. I am not surprised by the 60 percent complete response figure."
Trindade told Oncology Times, "At Northshore-LIJ, we do liquid nitrogen cryospray ablation. The first line therapy is endoscopic mucosal resection for T1a/superficial esophageal cancer. The majority of the time endoscopic mucosal resection is possible. If it is not possible we then proceed to cryotherapy. For T1b disease, which is usually diagnosed after endoscopic mucosal resection, we usually refer for surgery. If they are not surgical candidates, we can do cryotherapy in conjunction with chemo or radiation. We also use cryotherapy for debulking large tumors for palliative purposes."
Esophageal Cancer Research
In the study, Tsai and colleagues enrolled patients retrospectively and prospectively in an open-label registry and patients in a retrospective cohort from 12 academic and community practices. Endoscopic spray cryotherapy was performed until local tumor eradication was confirmed by biopsy or until treatment was halted due to progression of disease, patient withdrawal, or comorbidities.
Included in the study were108 patients. Their median age was 75.5 years. He reported 79.6 percent were men, and about 92 percent of the patients were white. Histologically, 93.5 percent of the cancers were adenocarcinomas; the rest were squamous cell carcinomas. The average length of the lesions was 5.2 centimeters.
The patients underwent a mean of 4.2 treatments, or 442 treatments overall. Tsai said 40 patients were diagnosed with T1a disease, 27 patients were diagnosed with T1b disease, 10 patients were diagnosed with unspecified T1 disease, 15 patients were diagnosed with T2, and 16 patients did not have a T stage reported. Of the 106 patients who completed treatment, complete response of intraluminal disease was observed in 54.7 percent of patients. A 50 percent complete response was seen in patients for whom no T stage was reported.
Mean follow-up was 17.3 months. During that period. 21 patients died due to cancer, and 12 other patients died but their deaths were not related to cancer or treatment. None of the deaths were related to treatment. No treatment-related perforations were observed. Strictures developed in 11 of 108 patients, but those strictures were observed in three of those 11 patients prior to spray cryotherapy, Tsai said.
"This is actually well-tolerated. Some patients complain of difficulty in swallowing; others report having a sore throat," he said. About 10 percent of patients reported dysphagia; 8 percent reported a sore throat. None of the patients required hospitalization for the adverse events.
Ed Susman is a contributing writer.