Positive predictive value of the clinical diagnosis of T1a-EP/LPM esophageal cancer depends on lesion size.

OBJECTIVES Endoscopic resection (ER) is a minimally invasive treatment for esophageal squamous cell carcinoma (ESCC). However, stricture may develop after ER for widespread lesions. Application of ER is justified if these cancers are pathological T1a-epithelial/lamina propria (pEP/LPM) cancers that can be cured by ER. We conducted a study to clarify the association between pathological invasion depth and lesion size or circumference in clinical (c) EP/LPM cancers. METHODS From our database, we identified patients diagnosed with cEP/LPM ESCC via endoscopic examination who underwent endoscopic or surgical tumor resection. The accuracy of cEP/LPM ESCC diagnosis was determined by histologically diagnosing cancer invasion depth as a reference standard. RESULTS Between January 2015 and December 2019, 1,271 cancer patients were diagnosed with cEP/LPM ESCC, of which 1,195 (94.0%) were correctly diagnosed with pEP/LPM cancer. Positive predictive value (PPV) classified according to lesion sizes of ≤25 mm, 26-49 mm, and ≥50 mm was 95.8% (981/1024 lesions), 89.7% (191/213 lesions), and 67.6% (23/34 lesions), respectively. PPV according to the circumferential extent of <3/4, ≥3/4 and <1, and whole was 94.6% (1164/1230 lesions), 75.0% (24/32 lesions), and 77.8% (7/9 lesions), respectively. In multivariate analysis, the PPV of cEP/LPM ESCC was significantly associated with lesion size (P <0.001) and male sex. CONCLUSIONS PPV of cEP/LPM ESCC is related to lesion size. Treatment should be determined considering the high risk of cancer invasion into the muscularis mucosa or deeper in cEP/LPM cancers with a lesion size of ≥50 mm.