Feasibility of a New System of Classification of Submucous Myomas: a Multicenter Study

Objective: To evaluate the performance of the STEPW (size, topography, extension, penetration, wall) classification system in predicting partial or complete fibroid removal on hysteroscopic myomectomy.

Design: Multicenter, prospective study (Canadian Task Force classification II-2).

Setting: Four hysteroscopy centers in Brazil, China, Italy, and the United States.

Patient(s): Four hundred forty-nine women who underwent hysteroscopic resection of 465 submucous fibroids.

Intervention(s): Resection of the submucous fibroids (hysteroscopic myomectomy). Fibroids were scored according to the European Society for Gynaecological Endoscopy (ESGE) and STEPW classifications. The validation of the two classifications was assessed using sensitivity and specificity of each classification, with their best cutoff point. A test of equality of the two areas under the receiver operating characteristic curves was performed for correlated samples.

Main Outcome Measure(s): Correlation of ESGE and STEPW classifications with complete or incomplete removal of submucous fibroid.

Result(s): Removal of the myoma was complete in 432 (92.9%) of 465 myomectomies and incomplete in 33 (7.1%). All 320 fibroids (100%) with a score≤4 in the STEPW classification were completely removed, and 112 of 145 fibroids (77.2%) with a score>4 were removed. All 33 cases of incomplete hysteroscopic myomectomy (100%) had a STEPW score>4. Using the ESGE classification, 85 of 86 cases (98.9%) of type 0 fibroids, 278 of 298 (93.3%) of type 1, and 69 of 81 (85.2%) of type 2 were completely resected.

Conclusion(s): Classifying submucous fibroids using the STEPW classification permits greater correlation with complete or incomplete removal of the myoma by hysteroscopic myomectomy.