Riassunto analitico
Arteriovenous malformations (AVMs) represent one type of congenital vascular
anomalies marked by morphostructural alterations in vessels and connections
between arteries and veins. Absence of ordinary capillary network causes a
significant hemodynamic alteration. AVMs are identified by high flow and low
resistance. In the course of embryogenesis, primary plexus undergoes an altered
maturation, due to predominantly somatic genetic mutations (MAP2K1, KRAS and
BRAF) that lead to dysplastic vessels and modified connections between arteries and
veins, the so-called "nidus".
Although effective, current treatment approaches are often very invasive or
destructive. Surgery, for example, is an excellent way to treat AVMs, however it has
limitations such as possible relapses, if whole malformation and nidus are not
eradicated. Moreover, treatment approach can be a very destructive one, while other
interventions can lead to significant sequelae, in both functional and aesthetical
perspective. Furthermore, embolization with ethanol represents an effective method,
but complications may arise in the course of treatment, such as nerve damage,
hemodynamic collapse, necrosis, and lung damage.
Aim of this pilot study is show a first analysis on the efficacy of bleomycin
suggesting intralesional interstitial administration as single approach or in association
with surgery, in order to achieve effective treatments that improve prognosis and
quality of life for patients affected by arteriovenous malformations.
Out of 14 enrolled adult patients affected by arteriovenous malformations at cervicalfacial region with SEC-g S3 staging, 9 ones were suggested with bleomycin singlemode treatment, while 5 patients underwent bleomycin plus surgery.
Following local anesthesia, 15,000 IU bleomycin (diluted in 5 or 15 cc of
physiological solution depending on lesion size) were administered
using an intralesional interstitial approach. Injections were guided by ultrasound.
Therapeutic assessment happened through clinical approach, echocolordoppler and
MRI.
Patients underwent a 1-year follow-up. Out of them, 9 patients (64.3%) achieved
control period, 5 ones (35.7%) are carrying on follow-up or waiting for surgery. For
patients who completed follow-up time frame (64.3%), data collected proved that
bleomycin led to a complete remission of malformation in 8
patients out of 9 ones (88.9%), while in the same group just one single patient did not
experience complete remission (11.1%).
5 patients were suggested to combine bleomycin with surgical intervention (35.7%).
Out of them, 2 completed follow-up while one experienced a thorough remission of
disease.
Reported side effects are in line with literature: two cases of nausea, one case of
fever, one transient alopecia, one lip necrosis and one flagellated dermatitis.
Intralesional interstitial bleomycin is thought to be more appropriate than
intravascular bleomycin, as the drug reaching systemic circulation is in smaller
quantity and side effects will be fewer, as a result.
Evidence that the drug may not remain long enough in contact with flawed cells
represents another limitation of intravascular approach, when compared to
administration of intralesional interstitial bleomycin.
This occurs because AVMs are high-flow malformations and treatment may not turn
out as effective.
Although preliminary, data collected in this study show that bleomycin could be a
good procedure in treating small sized AVMs both as a single method and in
combination with surgery. Therefore, further analyses and trials on this kind of
treatment are of paramount importance.
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