A rare form of ectopic pregnancy-cornual ectopic

V S Thrupthi¹, Indira H^2*, Dwarakanath L³, Girish B L⁴

¹Post Graduate, ²Professor and Head, ³,⁴Professor, Department of Obstetrics & Gynaecology
Sri Siddhartha Medical College, SSAHE, Tumkur,
Karnataka, India

* Corresponding author

Abstract
Background : Interstitial and cornual ectopic pregnancy is rare, accounting for 2–4% of ectopic pregnancies and remains the most difficult type of ectopic pregnancy to diagnose due to low sensitivity and specificity of symptoms and imaging. The site of implantation of embryo occurs in the intrauterine part of the fallopian tube and invasion through the wall of uterus make this pregnancy tough to differentiate from an intrauterine pregnancy on ultrasound examination. Mortality is high in this type of pregnancy due to delay in diagnosis ,rupture at the site of implantation,internal haemorrhage in addition to speed of hemorrhage. Case report: A 29-year-old lady, G3P2L2, referred to our hospital at 7+3 weeks of gestation as a suspected case of cornual ectopic pregnancy. She presented with bleeding since 15 days, On admission, she was stable hemodynamically. Abdominal examination was normal. On per vaginum examination OS was closed with minimal bleeding,uterus was bulky with right forniceal tenderness and cervical motion tenderness. USG done outside shows thick walled cystic lesion with significant peripheral vascularity in the right adnexa/corneal end of right fallopian tube measuring 5.9x4.4cms suggesting cornual ectopic. On admission, her Beta-hCG was 9169 IU/l.She was conselled and she opted for surgery.OT findings were right cornual ectopic of size 6x6cms extending intramurally.Hysterectomy is done after taking consents to stop bleeding.After excising the specimen fetal pole with membranes present.HPE confirmed ectopic gestational sac. Follow-up was done with weekly serum beta hCG till it became <2 IU/l and pelvic USG. Subsequent decline in serum beta hCG and reduction in size of ectopic gestational sac were noted on USG.
Key words: Ectopic,Cornual Ectopic,Interstitial Ectopic,Hysterectomy.

Introduction
Interstitial and cornual Ectopic is very rare and one of the most dangerous forms of ectopic pregnancy, counting 2-4% of ectopic pregnancies.[1] Usually the term cornual ectopic  is interchangeable with interstitial pregnancy. As per definition, a cornual ectopic refers to implantation and the development of a gestational sac in either of the upper and lateral portions of the uterus. Apparently, an interstitial pregnancy is the implantation of gestational sac within the proximal,intramural portion of the fallopian tube which is enveloped by the myometrium.[2] The interstitial portion is almost 0.7 mm in width and 1-2 cm in length. The myometrial tissue that is surrounding the ectopic , allows progression of the pregnancy into second trimester, but rupture at that late gestation may result in cataclysmic hemorrhage with a mortality of up to 2%.
Interstitial and cornual ectopic remains the most difficult type of ectopic pregnancy to diagnose because of its low sensitivity and specificity of symptoms and imaging. The site of implantation in the intrauterine portion of fallopian tube and invasion through the uterine wall makes this pregnancy difficult to differentiate from an intrauterine pregnancy on ultrasound. The ultrasound features proposed for identifying and diagnosing this condition are: an empty uterine cavity,gestational sac located eccentrically  1 cm from the most lateral wall of uterine cavity, thin (<5mm) myometrial layer surrounding gestational sac.[3] ''Interstitial line sign'' extending from upper region of the uterine horn to border the intramural portion of fallopian tube has also been tried and used.[4] Routinely, treatment of interstitial ectopic has been surgical and may include cornual resection by laparoscopy or laparotomy depending on patient situation and surgical expertise or hysterectomy.
Case report
A 29-year-old lady, G3P2L2, referred to our hospital at 7+3 weeks of gestation as a suspected case of cornual ectopic. She presented with bleeding since 15 days. On admission, she was stable hemodynamically. Abdominal examination appeared to be normal. On per vaginum examination:OS closed with minimal bleeding,uterus was bulky with right forniceal tenderness and cervical motion tenderness.USG done outside shows thick walled cystic lesion with significant peripheral vascularity [Figure 1] in the right adnexa/cornual end of right fallopian tube measuring 5.9x4.4cms suggesting cornual ectopic. On admission, her Beta-hCG was 9169 IU/l. She was counselled for surgery and posted for laparotomy. Intraop findings were right cornual ectopic of size 6x6cms with vascularity extending intramurally [Figure 3]. Hysterectomy was done after taking consent [Figure 4]. After excising the specimen fetal pole with membranes were identified [Figure 5]. HPE confirmed ectopic gestational sac. Patient was discharged on postop day.[5] Follow-up with weekly serum beta hCG was done till it became <2 IU/l or negative card test (UPT kit). Subsequent there was a decline in serum beta hCG.

Figure 1: Ultrasonography showing peripheral vascularity of right cornual ectopic

Figure 2: USG showing right cornual ectopic with fetal pole

Figure 3: Intraoperative image of right cornual ectopic

Figure 4: Hysterectomy specimen with cornual ectopic extending intramurally

Figure 5: Cut-section of cornual ectopic with fetal pole
Discussion
Recognising Interstitial and cornual ectopic pregnancy earlier is necessary. Various treatment options exist for the management of this condition. Ultrasound assessment and a high index of suspicion have allowed diagnosing this condition earlier and increased success of managing interstitial ectopic pregnancy conservatively. Generally,treatment for interstitial and cornual ectopic has been cornual resection by laparoscopy/ laparotomy or hysterectomy can be done in cases which present with hypovolemic shock or ruptured uterus or when the size pf ectopic is >5cms with vascularity. If cornual pregnancy is medium-sized (<5 cm) with initial beta hCG value of <5000 IU/ml, conservative management with methotrexate need to be used with caution . In general, methotrexate treatment has been associated with a failure rate of 9-65%.[5] In this patient as the size of the cornual ectopic is >4cms, medical management could not be attempted.
Conclusion
Diagnosing early and management at appropriate time is the key in the treament interstitial and cornual ectopic pregnancy. With gaining expertise in ultrasonography and  gynaecologists learning advances in laparoscopic skills progressively, conservative medical management and conservative surgical measures are being used in treating interstitial ectopic and cornual ectopic.
Acknowledgement: NIL
Financial support and sponsorship: NIL
Conflict of interest: NIL

References
1.   Faraj R, Steel M. Management of cornual (interstitial) pregnancy. Obstet Gynaecol. 2007;9:249–55.
2.   Malinowski A, Bates SK. Semantics and pitfalls in the diagnosis of cornual/interstitial pregnancy. Fertil Steril. 2006;86(6):1764.e11–4.
3.   Timor-Tritsch IE, Monteagudo A, Materna C, et al. Sonographic evolution of cornual pregnancies treated without surgery. Obstet Gynecol. 1992;79:1044–9.
4.   Ackerman TE, Levi CS, Dashefsky SM, et al. Interstitial line: sonographic finding in interstitial ectopic pregnancy. Radiology. 1993;189:83–7.

Address for Correspondence:
Dr. H. Indira, Professor & HOD, Department of Obstetrics & Gynaecology, Sri Siddhartha Medical College, SSAHE Tumkur Karnataka India.
Email: drindirah@gmail.com