Endoscopic detection of early esophageal cancer in a high-risk population: does Lugol staining improve videoendoscopy?

Endoscopic therapeutic esophageal interventions

Cyanoacrylat and fibrin glue seem to be no better alternatives to ligation in the treatment of bleeding esophageal varices. Studies with photodynamic therapy (PDT) of high-grade dysplasia (HGD) and early esophageal cancer show encouraging results. The use of 5-aminolaevulinic acid (ALA) as a photosensitizer minimizes the rate of severe side effects, but only in HGD and tumors with a depth of 2 mm or less can a complete remission be achieved. The use of Lugol's iodine solution is sensible for the detection of HGD and early squamous cell cancers. Thermal ablation with Neodym:YAG laser and self-expanding metal stents are the most important modalities for palliative treatment of esophageal cancer.

Mucosal iodine staining improves endoscopic visualization of squamous dysplasia and squamous cell carcinoma of the esophagus in Linxian, China

BACKGROUND

In previous studies in the high risk population of Linxian, China, the majority of foci of high grade (moderate and severe) squamous dysplasia (HGD) and invasive squamous carcinoma (CA) of the esophagus were associated with endoscopically visible lesions that could be targeted for biopsy, but some foci of HGD were missed by routine endoscopic examination. This study examined whether spraying the mucosa with Lugol's iodine solution, which stains normal epithelium brown but leaves dysplasia and carcinoma unstained, could improve endoscopic detection and delineation of these lesions.

METHODS

Two hundred twenty-five Linxian adults with balloon cytologic evidence of dysplasia or carcinoma underwent endoscopy. All visible lesions were described and photographed before and after staining with 1.2% Lugol's iodine solution. Biopsies were taken from all lesions visible before staining, from all unstained lesions (USLs) after applying the stain, and from representative control areas of stained mucosa.

RESULTS

Two hundred fifty-three USLs and 255 control sites were biopsied. No complications occurred. Ninety-four biopsy sites contained HGD and 20 contained CA. Before staining, the sensitivity of visible lesions for identifying HGD or CA was 62%, and the specificity was 79%. After staining, the sensitivity of USLs for identifying HGD or CA was 96%, and the specificity was 63%. Eighty-eight percent of the HGD and CA lesions were larger or more clearly defined after staining. The diagnostic lesions in 17 of 31 patients with moderate dysplasia (55%), 8 of 35 patients with severe dysplasia (23%), and none of the 19 patients with invasive carcinoma (0%) were identified only after staining.

CONCLUSIONS

Mucosal iodine staining improved endoscopic detection and delineation of HGD and CA in these patients. This simple technique is highly sensitive for identifying these precursor and invasive squamous lesions, and it should be used whenever optimal visualization of squamous mucosal abnormalities is required.

Chromoendoscopy--where is it useful?

Tissue staining during endoscopy (chromoendoscopy) is a technique used to study the fine details of the mucosa throughout the gastrointestinal tract. Unfortunately, its applications and results are not known by many gastrointestinal or surgical endoscopists. Each stain has a few specific clinical applications. The mechanism of action of the stains should be fully understood before their use. Ideally, the clinician should use chromoendoscopy and the variety of stains either to confirm a clinical suspicion or to provide new information that could aid management in a specific setting. Endoscopic tattooing is a different technique where a specific site in the gastrointestinal tract is labeled by an intramural injection of a carbon ink suspension solution for future surgical or endoscopic identification.

Cytologic detection of esophageal squamous cell carcinoma and precursor lesions using balloon and sponge samplers in asymptomatic adults in Linxian, China

BACKGROUND

The principal reason for the poor prognosis of esophageal carcinoma is that most tumors are asymptomatic and go undetected until they are unresectable. Previous studies have shown that cytologic screening of asymptomatic high risk individuals can detect curable esophageal carcinomas and precursor lesions, but the sensitivity of such screening is not well documented. The current study evaluated the sensitivity and specificity of currently available balloon and sponge cytologic samplers for detecting biopsy-proven squamous dysplasia and carcinoma in asymptomatic individuals from a high risk population in Linxian, China.

METHODS

Asymptomatic adults were examined with both balloon and sponge samplers, in random order, followed by endoscopy with mucosal iodine staining and biopsy of all unstained lesions. The cytology slides were interpreted using the criteria of the Bethesda System. The balloon and sponge cytologic diagnoses (test) were compared with the biopsy diagnosis (truth) in each patient to estimate the sensitivity and specificity of each sampler.

RESULTS

Of the 439 patients with adequate biopsies, 123 (28%) had histologic squamous dysplasia and 16 (4%) had an invasive squamous carcinoma. The sensitivities/specificities of the balloon and sponge were 44%/99% and 18%/100%, respectively, for detecting biopsy-proven squamous cell carcinoma, and 47%/81% and 24%/92%, respectively, for identifying squamous dysplasia or carcinoma.

CONCLUSIONS

In this study, the balloon sampler was more sensitive than the sponge sampler for detecting esophageal squamous disease, but both techniques were less than optimal. Improved samplers and/or cytologic criteria should increase the sensitivities observed in this baseline study.

Cytologic detection of esophageal squamous cell carcinoma and precursor lesions using balloon and sponge samplers in asymptomatic adults in Linxian, China

BACKGROUND

The principal reason for the poor prognosis of esophageal carcinoma is that most tumors are asymptomatic and go undetected until they are unresectable. Previous studies have shown that cytologic screening of asymptomatic high risk individuals can detect curable esophageal carcinomas and precursor lesions, but the sensitivity of such screening is not well documented. The current study evaluated the sensitivity and specificity of currently available balloon and sponge cytologic samplers for detecting biopsy-proven squamous dysplasia and carcinoma in asymptomatic individuals from a high risk population in Linxian, China.

METHODS

Asymptomatic adults were examined with both balloon and sponge samplers, in random order, followed by endoscopy with mucosal iodine staining and biopsy of all unstained lesions. The cytology slides were interpreted using the criteria of the Bethesda System. The balloon and sponge cytologic diagnoses (test) were compared with the biopsy diagnosis (truth) in each patient to estimate the sensitivity and specificity of each sampler.

RESULTS

Of the 439 patients with adequate biopsies, 123 (28%) had histologic squamous dysplasia and 16 (4%) had an invasive squamous carcinoma. The sensitivities/specificities of the balloon and sponge were 44%/99% and 18%/100%, respectively, for detecting biopsy-proven squamous cell carcinoma, and 47%/81% and 24%/92%, respectively, for identifying squamous dysplasia or carcinoma.

CONCLUSIONS

In this study, the balloon sampler was more sensitive than the sponge sampler for detecting esophageal squamous disease, but both techniques were less than optimal. Improved samplers and/or cytologic criteria should increase the sensitivities observed in this baseline study.