Can achalasia cardia (a swallowing disorder characterized by the inability of food to pass through the esophagus) be mistaken for pseudoachalasia (a condition that mimics achalasia, often caused by an underlying malignancy) on contrast-enhanced computed tomography (CECT) scans in adults presenting with symptoms of dysphagia, regurgitation, and weight loss?

Can Achalasia Be Mistaken for Pseudoachalasia on CECT?

No, the diagnostic challenge runs in the opposite direction—pseudoachalasia mimics achalasia, not the other way around, and CECT is specifically useful for distinguishing pseudoachalasia (often malignancy-related) from true achalasia by identifying asymmetric or marked wall thickening (>10 mm) and masses that indicate underlying malignancy. 1

Understanding the Diagnostic Relationship

The clinical reality is that pseudoachalasia accounts for approximately 4% of patients presenting with achalasia-like symptoms, and in about 70% of these cases, the underlying cause is malignancy, most commonly adenocarcinoma of the gastroesophageal junction or cardia. 2, 3 This means the concern is not that achalasia mimics pseudoachalasia, but rather that pseudoachalasia can be mistaken for benign achalasia, leading to inappropriate treatment and delayed cancer diagnosis. 4

CECT Findings That Distinguish the Two Conditions

True Achalasia on CECT:

• Symmetric esophageal wall thickening of <10 mm at the gastroesophageal junction 1
• Esophageal dilation (present in 6 of 8 patients in one series) 1
• Smooth, uniform appearance without mass lesions 1

Pseudoachalasia on CECT:

• Asymmetric wall thickening at any thickness 1
• Marked symmetric wall thickening >10 mm 1
• Presence of a discrete mass lesion 1
• More pronounced esophageal dilation with irregular contours 1

The critical threshold is 10 mm of symmetric wall thickening—below this, achalasia is likely; above this or with any asymmetry, pseudoachalasia from malignancy should be strongly suspected. 1

Clinical Red Flags for Pseudoachalasia

When evaluating patients with achalasia-like symptoms, pseudoachalasia should be suspected in patients with:

• Advanced age at onset (pseudoachalasia represents about 9% of suspected achalasia cases in patients over 60 years) 4
• Shorter duration of symptoms (versus the typical 0.5-2.8 years in achalasia) 5, 3
• Profound weight loss 3
• Difficulty passing the gastroesophageal junction on endoscopy 3

Recommended Diagnostic Algorithm

When CECT shows any concerning features (asymmetric thickening, >10 mm symmetric thickening, or mass), the following workup is mandatory: 6

1. Upper endoscopy with careful retroflexed examination of the gastroesophageal junction and multiple biopsies (though this can be false negative in 25% of cases) 7, 3

2. Endoscopic ultrasound (EUS) with guided biopsy plays an increasingly important role and should be performed when endoscopy is non-diagnostic but suspicion remains high 6, 3

3. High-resolution manometry to confirm the diagnosis, though it cannot reliably distinguish achalasia from pseudoachalasia 4

Critical Clinical Pitfall

The most dangerous error is performing pneumatic dilation or POEM on a patient with undiagnosed pseudoachalasia from malignancy. 4 This delays appropriate cancer treatment and can cause serious complications. Therefore, EUS or CT imaging of the esophagogastric junction should be performed to clarify the etiology whenever there is clinical suspicion or atypical features. 6

Management Implications

• For confirmed achalasia (symmetric thickening <10 mm on CECT, negative malignancy workup), proceed with standard achalasia treatment based on Chicago Classification subtype 7, 8

• For pseudoachalasia from malignancy, treatment is directed against the tumor or may be palliative to maintain luminal patency 2

• For indeterminate cases (symmetric thickening 10-18 mm), EUS with biopsy is essential before any definitive intervention 1