Pilot Study: Utilizing Manometry to Assess Radiation-Induced Changes in Esophageal Function

As there is no standard of care to evaluate/visualize the effects of radiation therapy (RT)
-induced esophageal injury, this is routinely assessed by patient reported accounts, and the
symptoms are then managed supportively (e.g. with pain medicines, parenteral nutrition,
feeding tubes etc). Manometry has been frequently used to study the effects of RT on
gastrointestinal function in the setting of numerous malignancies, including colorectal,
cervical and prostate cancers. What is often seen after RT is decreased sphincter function
in the anorectal region leading to problems with continence and fecal urgency, however there
has not been as rigorous of an evaluation of esophageal function after RT.

One study performed more than 15 years ago included only 4 patients with lung cancer and
concluded that mucosal irritation was likely the primary cause of RT-associated esophageal
injury and no abnormalities in motility were seen. Radiation is known to cause long-term
esophageal injury including stricture, and there is manometric evidence of impaired motility
long-term after RT. The recent introduction of high-resolution manometry permits more
extensive evaluation of the effects of RT on esophageal function.

Inclusion Criteria:

- Age ≥ 18 years or older

- Absence of any severe disorders of esophageal motility (patients with reflux and/or a
hiatal hernia are eligible)

- Histologically confirmed lung cancer scheduled to undergo conventionally fractionated
radiation treatment

- Patients that will be treated with a minimum of 45 Gy of radiation therapy

- Patients with mediastinal nodal disease, or primary lesions that are near the
esophagus are eligible provided that they are not having esophageal symptoms believed
to be due to the tumor.

Exclusion Criteria:

- History of esophageal motility disorder that pre-dates and is unrelated to the
present diagnosis of lung cancer

- History of any prior radiotherapy to the esophagus

- Pregnant or lactating women

- Inability to understand and follow swallowing instructions for the esophageal
manometry procedure; this is to ensure patient compliance of performing the breath
hold technique throughout the radiation therapy treatment

- Patients with mediastinal nodal disease, or primary lesions, that are having
esophageal symptoms believed to be due to the tumor