Endoesophageal Cryotherapy For Ablating Barrett's Esophagus and Early Stage Esophageal Cancer

Summary

In this prospective single center study, up to 25 patients with Barrett's esophagus with LGD or no dysplasia (Group 1), 25 patients with HGD/IMCA (Group 2), 25 patients with esophageal carcinoma confined to the esophageal wall (Group 3) and 25 patients with severe esophageal squamous dysplasia (Group 4) will be treated with endoscopic cryotherapy. This study is single arm and no blinding will be utilized. Interim analysis of the data will be reviewed with a DCI statistician after 14 patients in each group have been treated with cryotherapy and if safety and efficacy is documented to that point in time, we will request the ability to extend the enrollment to a maximum allowable amount of 25 patients per group. The proposed study duration is seven years, allowing two years for patient enrollment and 5 years for post treatment follow-up. Study duration per patient will total approximately six years.

Patients with Barrett's esophagus with no dysplasia or low grade dysplasia (group 1) will be treated with cryotherapy at six week intervals until Barrett's mucosa is ablated or six treatments are administered. Patients with Barrett's HGD and IMCA or severe esophageal squamous dysplasia (groups 2 and 4) will be treated with cryotherapy at six-week intervals until Barrett's mucosa is ablated or six treatments are administered. More advanced mass lesions are typically more difficult to eradicate with ablative therapies and may progress faster than patients with IMCA, therefore, patients with more advanced cancer (group 3) will be treated every 2 weeks until the lesion is eradicated up to eight treatments.

After cryotherapy treatment is complete (i.e. the esophagus has re-epithelialized with normal squamous epithelium for Groups 1, 2, 4 and the tumor is locally controlled/absent in Group 3), patients will be assessed by endoscopy and biopsy every three months for one year, every six months for two years, then annually for two years (flow sheet - appendix 1; study schedule - appendix 2).

Conditions

• Barrett's Esophagus

Interventions

PROCEDURE

Endoscopic spray cryotherapy

A special orogastric venting tube is passed alongside the endoscope and the cryocatheter then used to perform cryotherapy. Liquid nitrogen is sprayed through the catheter to achieve a uniform white frost in a hemicircumferential sector for 10 seconds. A thaw time of 45-60seconds is observed. This freeze-thaw cycle is repeated x 3 for a total of 40sec cryotherapy per segment. This therapy is repeated every 6 weeks until visible re-epithelialization is seen or a maximum of 6 sessions. Once a squamous lining is seen, biopsies are taken throughout the original area to assess for buried Barretts. If none is seen, followup with 4 quadrant q2cm biopsies are taken at 3,6,9,12, 18, 24, 36, 48 months.

PROCEDURE

Endoscopic spray cryotherapy

After passing a special orogastric venting tube, the cryocatheter is used to spray liquid nitrogen onto the tumor to achieve a white frost (frozen state) for 20 seconds. A 45-60 sec thaw is allowed and then retreatment x 2 for a total of 60 seconds therapy per session. Repeat treatments are permitted every 2 weeks for a maximum of 8 treatments.

Sponsors & Collaborators

• CSA Medical, Inc.

  collaborator INDUSTRY

• Walter Reed Army Medical Center

  lead FED

Principal Investigators

• John D Horwhat, MD · Walter Reed Army Medical Center

Study Design

Allocation

NON_RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Max Age

85 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2007-03-31

Primary Completion

2010-03-31

Completion

2012-03-31

Countries

• United States

Study Locations