Society: ASGE

Background and Aims

Recently macroscopic-onsite evaluation (MOSE) technique for Endoscopic Ultrasound guided Tissue acquisition (EUS-TA) for solid gastrointestinal lesions has been advocated to provide high diagnostic accuracy in settings where rapid- onsite evaluation is not available. However, MOSE technique has not yet been standardized. Our aim was to compare MOSE guided EUS-TA with conventional techniques and to find out the optimum parameters required for MOSE technique.

Materials and Methods

In this prospective randomized study, 96 consecutive adult patients undergoing EUS-TA were randomized to MOSE and conventional groups. MOSE technique was performed by segregating material obtained in each pass into Macroscopically visible Core (MVC), and red paste. Obtaining total MVC length greater than 4 mm was considered complete, and no further passes were taken. Sensitivity, specificity, positive predictive value, negative predictive value, diagnostic yield, diagnostic accuracy was compared between two arms. Optimum length and number of MVC required was also evaluated.

Results

When comparing MOSE group (n=48) with conventional group (n=48), diagnostic accuracy, sensitivity ,specificity, positive predictive value and negative predictive value were 97.9% vs 95.8%,93.3 % vs 79.4%, 100 % vs 100%, 100 % vs 100% and 90% vs 87.8% respectively (Table 1).Diagnostic yield was similar in both the groups (95.8% vs 91.6%, p=0.39).The mean length of MVC obtained was 15.46 ± 3.22 mm and number of MVC obtained was 3.17 ± 0.83 in MOSE group. No significant difference in duration of procedure and adverse events were noted in two groups. Number of passes needed in MOSE group was significantly less then needed in conventional arm ( median 2 vs 3 , mean 2.08 ± 0.28 vs 2.65 ± 0.53, p <0.001). Obtaining a 11.5 mm length of MVC was 93.3% sensitive whereas obtaining total 2.5 number of MVC was 86.7% sensitive to diagnose malignancy (Figure 1).

Conclusion

MOSE technique guided EUS-TA results in fewer number of passes needed to achieve high diagnostic accuracy and diagnostic yield without increasing the procedure duration and adverse events as compared to conventional technique. Obtaining longer length and more number of MVC increases the sensitivity to diagnose malignancy.

<b><u>TABLE 1: Comparing the clinical details, technical parameters, diagnostic accuracy and diagnostic yield between MOSE group and Conventional group. </u></b>

TABLE 1: Comparing the clinical details, technical parameters, diagnostic accuracy and diagnostic yield between MOSE group and Conventional group.

FIGURE 1 : Area under the receiver operating characteristic graph shows that in in patients where Macroscopic onsite evaluation (MOSE) was used, obtaining a total Macroscopic visible core (MVC) length of 11.5 mm had 93.3% sensitivity and obtaining 2.5 MVC cores (each 4 mm) had 86.7% sensitivity in diagnosing malignancy.

FIGURE 1 : Area under the receiver operating characteristic graph shows that in in patients where Macroscopic onsite evaluation (MOSE) was used, obtaining a total Macroscopic visible core (MVC) length of 11.5 mm had 93.3% sensitivity and obtaining 2.5 MVC cores (each 4 mm) had 86.7% sensitivity in diagnosing malignancy.

Nikhil Sonthalia

Appearances