POEM Trial Results Hold Firm for Long-Term Efficacy in Achalasia

Peroral endoscopic myotomy (POEM) may be the best bet as first-line treatment for treatment-naive patients with achalasia, according to long-term trial data.

POEM offered greater long-term efficacy and a low risk of treatment-related complications versus pneumatic dilation for the condition, wherein the esophagus fails to relax and prevents food from passing into the stomach, reported Albert Bredenoord, MD, PhD, of the Amsterdam University Medical Center, and colleagues.

In a modified intention-to-treat analysis with 125 patients, the primary outcome of treatment success at 5 years -- defined as an Eckardt score ≤3 with no severe complications related to treatment and no need for retreatment -- was twice as common with POEM compared to a single series of pneumatic dilation (81% vs 40%, P<0.0001), they stated in the Lancet Gastroenterology & Hepatology.

For patients in clinical remission at 5 years, a numerically higher proportion of patients who received POEM experienced endoscopy-confirmed reflux esophagitis (33% vs 13% for the pneumatic dilation group) and required proton-pump inhibitors (46% vs 13%, respectively, P=0.008), while no significant between-group differences were seen in Eckardt score, barium column height at 5 minutes, and median integrated relaxation pressure.

Bredenoord's group suggested that these longer-term findings -- which build upon the previously reported 2-year data -- suggest POEM should be offered as an initial treatment but "should not lead to abandonment of pneumatic dilation from clinical practice."

"Pneumatic dilation is less time-consuming, easier to learn, and is less likely to result in reflux esophagitis or reflux symptoms compared with peroral endoscopic myotomy," continued Bredenoord and colleagues. "Other reasons to prefer pneumatic dilation to peroral endoscopic myotomy are the need for general anesthesia with peroral endoscopic myotomy and a potentially prolonged hospital stay."

Achalasia is a rare condition that causes regurgitation, dysphagia, weight loss, and chest pain due to a lack of peristalsis and impaired relaxation of the lower esophageal sphincter, Bredenoord's group explained. Pneumatic dilation has been an effective treatment option, but often results in the need for repeat dilations. Laparoscopic Heller myotomy has similar efficacy, but is more invasive and carries a greater risk for complications. POEM, meanwhile, has shown promise with shorter recovery times without requiring an abdominal incision.

In an accompanying editorial, Zaheer Nabi, MD, DNB, and D. Nageshwar Reddy, MD, both of the Asian Institute of Gastroenterology in Hyderabad, India, explained that while POEM "was shown to be superior to a single series of graded pneumatic dilation at 5-year follow-up," its superiority "over graded plus on-demand pneumatic dilation has not yet been established."

They noted that the "high incidence of gastroesophageal reflux after peroral endoscopic myotomy should be taken into consideration during shared decision-making about the management of achalasia."

Nabi and Reddy advised that "a personalized and patient-centric approach should be adopted as per the available evidence," adding that POEM may be best for people younger than 40 years, those with type III achalasia, those who do not want repeat treatment sessions, and those with early relapses after graded pneumatic dilation.

From 2012 to 2015, Bredenoord and colleagues randomized 130 patients to either POEM or pneumatic dilation at six centers in Germany, Hong Kong, Italy, the Netherlands, and the U.S. The new follow-up data extend until January 2022.

Median patient age was 47-50 years, and more than half were male. To be eligible, patients had to have a new, symptomatic achalasia diagnosis with an Eckardt score >3. Two-thirds had achalasia subtype II, the median baseline Eckardt score was 7-8, and the median achalasia-related quality of life score was 24-25 (ranges from 10-33).

The pneumatic dilation group underwent dilation using a single 30-mm Rigiflex balloon, but if their Eckardt score remained >3, a second dilation with a 35-mm balloon or a 40-mm balloon was performed. If still unsuccessful, pneumatic dilation patients were offered POEM. If the Eckardt score was ≤3, high-resolution manometry was used, while a second balloon dilation of 35 mm was also performed if the integrated relaxation pressure reached 10 mm Hg or more.

At 5 years, eight of the pneumatic dilation patients were retreated, seven required additional dilations, and one had a laparoscopic Heller myotomy.

Reasons for treatment failure in both groups included recurrent symptoms (18% in the POEM group vs 40% in the pneumatic dilation group) or not experiencing an initial treatment effect (2% vs 19%, respectively). One patient who had pneumatic dilation experienced treatment failure caused by an adverse event (AE). Between 2 and 5 years after treatment, serious, non-intervention AEs included a case of stroke in the POEM group, a case of dementia in the pneumatic dilation group, and one death caused by a melanoma in the pneumatic dilation group.

Study limitations included its unblinded design and difficulty evaluating secondary outcomes.

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