Letrozole add-on in the Treatment of Cesarean Scar Pregnancy
Condition: Cesarean Scar Pregnancy
MeSH terms: Cicatrix
Study type: Interventional

Summary: 
      It is hypothesized that the inhibition of estradiol production by letrozole may interfere
      with physiological effects of progesterone necessary to maintain the pregnancy. There is no
      reference treatment of cesarean scar pregnancy (CSP) as the limited number of cases precludes
      the extrapolation of results. In our center we successfully use two-step treatment with
      methotrexate (MTX) followed by hysteroscopic removal of products of conception (POC). The
      time in between is needed to achieve a decrease in the trophoblast's vital potential (B-hCG
      fall) and its vascularization. Additional administration of letrozole could further reduce
      the vital potential of the pregnancy, eliminating the need for another dose of MTX, resulting
      in faster healing and lower rate of complications.
    

Detailed description: 
      A prospective cohort study is conducted among women with cesarean scar pregnancy (CSP). Women
      with increasing B-human chorionic gonadotropin (B-hCG) concentrations are included.

      Two study arms were planned:

        -  women treated with a single dose of 100 mg MTX intravenously and 50 mg MTX in
           intra-amniotic injection (day 0), along with 30 mg potassium chloride in case of
           positive fetal heartbeat (FH)

        -  women treated with a single dose of 100 mg MTX intravenously and 50 mg MTX in
           intra-amniotic injection (day 0), along with 30 mg potassium chloride in case of
           positive fetal heartbeat (FH) with additional use of letrozole 5 mg orally (from day 0)
           for 10 days.

      Blood parameters (B-hCG, hemoglobin, total blood count, creatinine, urea, alanine/aspartate
      transaminase, gamma-glutamyltransferase, bilirubin) were tested on days 0,4,7, followed by
      B-hCG concentration measurement every 7 days until surgery. After obtaining satisfactory
      decrease in B-hCG and POC vascularization, women underwent hysteroscopic evacuation of POC.
      Blood loss parameters, frequency of conversion from hysteroscopy to laparoscopy and
      laparotomy were measured.

      The women were given the option to choose the treatment used in the study. All enrolled women
      gave informed written consent to participate in the study.
    

Intervention name(s): MTX monotherapy; MTX + letrozole add-on
Intervention type(s): Drug; Drug
Intervention description(s): MTX in a single dose of 100 mg intravenously and 50 mg in intra-amniotic injection (day 0), along with 30 mg potassium chloride in case of positive fetal heartbeat (FH), and subsequent hysteroscopic evacuation of products of conception (POC); MTX in a single dose of 100 mg intravenously and 50 mg in intra-amniotic injection (day 0), along with 30 mg potassium chloride in case of positive fetal heartbeat (FH) + Letrozole in a daily dose of 5 mg (2 x 2.5 mg) orally for 10 days from day 0, and subsequent hysteroscopic evacuation of products of conception (POC)
Intervention MeSH terms: Letrozole
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: cesarean scar pregnancy; operative hysteroscopy