Related Experiment Video
Updated: Jun 26, 2026

Testing Targeted Therapies in Cancer using Structural DNA Alteration Analysis and Patient-Derived Xenografts
Published on: July 25, 2020
A case of a methotrexate-resistant ectopic pregnancy in which dactinomycin was effective as a second-line
Satoe Fujioka1, Yoshiki Yamashita, Sachiko Kawabe
1Department of Obstetrics and Gynecology, Osaka Medical College, Takatsuki, Osaka, Japan.
Objective:
To report a case of a methotrexate (MTX)-resistant heterotopic interstitial pregnancy in which dactinomycin was necessary as a second-line chemotherapy.
Design:
Case report.
Setting:
Medical college-affiliated hospital.
Patient(S):
A 39-year-old woman with vaginal bleeding after the transfer of two thawed 8-cell embryos.
Intervention(S):
MTX 50 mg/m(2) was given to the patient to treat a concomitant pregnancy in which an interstitial pregnancy and an intrauterine blighted ovum were identified. However, the patient's hCG level rose despite two MTX administrations. As a result, dactinomycin was then administered as a second-line chemotherapy. The patient's serum hCG level declined to a normal range after two administrations of dactinomycin.
Conclusion(S):
Dactinomycin could be an alternative in cases for which MTX is not effective and persistently high hCG levels exist.
Related Concept Videos
Treatment Resistant Cancers
Therapeutic Drug Monitoring: Affecting Factors
Targeted Cancer Therapies
There are several types of targeted therapies against specific...
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase