Study overview

This prospective, single-arm, clinical trial study was carried out in an educational referral hospital affiliated to Tehran University of Medical Sciences between September 2018 and September 2019. All participants with a history of hydatidiform mole were recruited. Lab data such as renal, liver and thyroid function test, complete blood count (CBC), and electrolytes was obtained. Indeed, beta-hCG titer was measured as a baseline.

An abdominopelvic ultrasound was performed to find any evidence of invasive mole, exclude a coexisting pregnancy, and look for possible metastatic disease. Chest radiography was ordered for all patients.

In the participants who desired to preserve fertility, uterine evacuation was performed. After dilatation, the molar tissue was evacuated with suction cannula 9 gauge and the clinician was performed a sharp curettage by curette at the end of the procedure.

In the follow-up period, patients were visited every week and the beta-hCG was measured by cobas analyzer for free beta subunit by ECL (Electrochemiluminescence). The standard created by International Federation of Gynecologists and Obstetricians (FIGO) for GTN diagnosis are as follow [13]:

1-

Beta- hCG plateau four values ± 10% recorded over a 3-week duration.

2-

Elevated beta-hCG level more than 10% of three values recorded over a 2-week duration.

3-

Detectable beta-hCG for more than 6 months after evacuation.

In the case of GTN, after staging by FIGO [14], hysteroscopy was performed by a surgeon with 15-year experience in the field of hysteroscopy, with 26 F KARL STORZ bipolar resectoscope fitted with an 8-mm cutting loop. Saline was used to distend the uterine cavity by controlling the amount of fluid (by means of Hysteroflator). We set the pomp on the least pressure that was 150 mmHg to minimize the cell spread via the fallopian tube. As in GTN, the uterus is similar to pregnancy; it is very prone to be traumatized with any manipulation. By using the loop without current as the curettage, all trophoblastic tissues were removed by gentle motions with minimal trauma application. Indeed, no misoprostol or prostaglandins were used for cervical preparing. Seven days after the procedure, beta-hCG was evaluated again.

Primary outcome was the evaluation of the change in serum beta-hCG levels after 1 and 7 days (a 10 log reduction regarding the primary levels). Secondary outcome was assessing the endometrial cavity for any remaining tissue 7 days after the procedure by transvaginal ultrasound (TVS) (Siemens probe, by a same radiologist who performed the first TVS). If beta-hCG had a plateaued or non-decreasing trend (<a 10 log reduction), the patients were candidate for chemotherapy. All the participants followed by measuring beta-hCG levels for 6 months until the levels would be undetectable.

Ethical statements

All participants sign the written informed consent. The oncologist explained the potential pros and cons of hysteroscopic resection and the advantages and disadvantages of chemotherapy as an alternative treatment. The study had been approved by TUMS ethics committee (Reference Number: 27546-30-03-94). It was registered in Iranian Registry of Clinical Trials (IRCT), (Reference Number: IRCT201601222576N11, 8/2016). This trial was conducted according to the principles of the Helsinki Declaration.

Inclusion and exclusion criteria

Inclusion criteria were the history of hydatidiform mole that beta-hCG titer in the follow-up did not reach negative value after uterine evacuation or the detecting molar tissue in the uterus by ultrasound. They were all eager to participate in the study. Exclusion criteria were patients who preferred chemotherapy instead of hysteroscopy or had unstable vital signs.

Statistical analysis

Data analysis was conducted by means of STATA version 14. (StataCorp, College Station, TX, USA). The Mann-Whitney U test was used for data analysis. P value less than 0.05 was considered significant. A CONSORT guideline was used for reporting the results.