Initial results from the prospective HEMBO-1 trial—presented at the Global Embolization Oncology Symposium Technologies (GEST) annual meeting (14–17 May, New York, USA) by Scott Thompson (Mayo Clinic, Rochester, USA)—indicate that haemorrhoidal artery embolization (HAE) using large particles combined with hydrogel coils may provide early improvements in bleeding symptoms and quality of life for patients with bleeding-predominant internal haemorrhoids.
Thompson described this haemorrhoid subset as a “clinically challenging condition” associated with substantial morbidity and reduced quality of life. According to the presenter, haemorrhoidal embolization has increasingly emerged as a minimally invasive treatment option for these patients, with prior studies suggesting symptom improvement in approximately 80% of cases.
The HEMBO-1 study was designed to evaluate the safety and efficacy of a combined embolization strategy using large embolic particles and coils. Thompson noted that uncertainty remains regarding the optimal embolization methodology, including the use of particles, coils, or opting for a combined approach.
The prospective, single-arm, single-centre trial aims to enrol 20 patients with bleeding-predominant internal haemorrhoids. At the time of presentation, 19 patients had been enrolled and 18 treated. The abstract focused on early outcomes from the initial seven treated patients.
Eligible patients had grade II or III internal haemorrhoidal disease and persistent or recurrent bleeding symptoms despite conservative management. Bleeding was required to be the predominant symptom. Patients with grade IV disease, prior haemorrhoidectomy, inflammatory bowel disease, portal hypertension, significant mesenteric venous disease, prior colorectal surgery, pelvic radiation, or ongoing chemotherapy were excluded.
The embolization technique used 800-micron particles in combination with hydrogel coils targeting branches of the superior rectal artery, with or without embolization of the middle rectal artery supplying the corpus cavernosum recti.
Among the first seven patients treated, the mean age was 55 years and five patients were male. Thompson outlined that four patients (57%) had grade II haemorrhoids, and three patients (43%) had grade III disease. Median duration of bleeding symptoms was five years, with a range of one to 20 years.
Thompson went on to highlight the clinical burden within the cohort, reporting that six of the seven patients had iron deficiency anaemia and three had previously required blood transfusions. Baseline bleeding scores and haemorrhoid bleeding scores were both elevated, with median scores of seven.
All procedures were performed via transfemoral access, added Thompson, who noted that technical success, defined as successful selective catheterisation and embolization of vessels supplying the corpus cavernosum recti, was achieved in 100% of cases.
Embolization of bilateral superior rectal artery branches alone was performed in four patients, while the remaining three underwent embolization of both superior and middle rectal artery branches, with a median of five vessels embolized per patient.
At three-month follow-up, Thompson reported “significant improvements” in bleeding-related outcomes. Median bleeding scores and haemorrhoid bleeding scores each improved by two points, while quality-of-life scores improved by one point. Pain scores did not significantly change, which Thompson noted was expected given that pain was “not a major baseline symptom in most patients”.
When asked whether they were satisfied with their symptom improvement, six of the seven patients (83%) reported satisfaction at three months, Thompson added. No peri-procedural or post-procedural complications were observed.
The presenter also highlighted one illustrative case involving a 30-year-old patient with a three-year history of grade III bleeding-predominant haemorrhoids, iron deficiency anaemia, and three prior banding procedures. Following embolization of five rectal artery branches, the patient reported marked improvement in bleeding frequency at 12 months, with bleeding scores reduced by half and quality-of-life scores improving from three to one. According to the presenter, the patient stated that the condition was “no longer a bother” in daily life.
Thompson then acknowledged several limitations of the study, including its single-centre design, small sample size, and currently limited follow-up duration.
Concluding his presentation, Thompson stated that early findings from HEMBO-1 suggest that HAE using large particles and hydrogel coils appears safe and may provide significant early improvements in bleeding symptoms and quality of life. He stated that ongoing enrolment and longer-term follow-up are expected to further define the role of this embolization strategy in this patient population.
