- Rationale: The optimal preoperative medical management for patients with a
pheochromocytoma is currently unknown. In particular, there is no agreement with respect
to whether phenoxybenzamine or doxazosin is the optimal alfa-adrenoreceptor antagonist
to be administered before surgical resection of a pheochromocytoma. We hypothesized that
the competitive alfa1-antagonist doxazosin is superior to the non-competitive alfa1- and
alfa2-antagonist phenoxybenzamine.
- Objective: comparing effects of preoperative treatment with either phenoxybenzamine or
doxazosin on intraoperative hemodynamic control in patients undergoing surgical
resection of a pheochromocytoma.
- Study design: Randomised controlled open-label trial.
- Study population: 18 - 55 yr old. Adult patients with a recently diagnosed benign
pheochromocytoma.
- Intervention: Patients are randomised to receive oral treatment with either
phenoxybenzamine or doxazosin preoperatively.
- Main study parameters/endpoints: The main study parameter is defined as the percentage
of intraoperative time that blood pressure is outside the predefined target range after
pretreatment with either phenoxybenzamine or doxazosin.
In this multicenter trial, we compare the effects of two commonly used drugs in patients
being medically prepared for resection of a benign pheochromocytoma. Participants are not
subjected to an experimental treatment of any kind, as we merely aim to describe in detail
the perioperative course in general and, in particular, the intraoperative hemodynamic
control in patients treated preoperatively with either phenoxybenzamine or doxazosin. A
routine diagnostic work-up for pheochromocytoma will be performed in all participants. One
extra blood sample (volume: 48,5 mL) is drawn before start of the study medication, and
participants need to record their symptoms in a diary. In addition, patients who are
pretreated in the outpatient clinic monitor their blood pressure and pulse rate at home with
an automated device. Treatment with an alfa-adrenoreceptor antagonist is initiated at least 2
- 3 weeks prior to surgery. Patients who are admitted to the hospital for pretreatment with
an alfa-adrenoreceptor antagonist have their blood pressure and pulse rate measured by the
nursing staff. The final site visit is planned at 30 days after surgery, in line with current
practice.
Phase:
Phase 4
Details
Lead Sponsor:
University Medical Center Groningen
Collaborators:
Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA) Atrium Medical Center Canisius-Wilhelmina Hospital Erasmus Medical Center Isala Leiden University Medical Center Maastricht University Medical Center Maxima Medical Center Medisch Spectrum Twente Onze Lieve Vrouwe Gasthuis Radboud University St. Antonius Hospital UMC Utrecht VU University of Amsterdam