Potential Carcinogenic Effects of Endovenous Laser Ablation

Millions of people worldwide are treated for venous disease. Ablation of the
great saphenous vein is one of the most performed treatments. More than 50
years the conventional surgical strip operation was the golden standard. In the
past decade the treatment of the great saphenous vein has become more minimally
invasive with the use of laser ablation / radio-frequency ablation and cryo
ablation. None of these techniques has any evidence benefits above the other.

The most performed minimally invasive treatment of the great saphenous vein
nowadays is the endovenous laser ablation (EVLA)
During EVLA a laser catheter is introduced in the great saphenous vein after
which it is thermally ablated using a constant temperature around 1000-1200
degrees Celsius for a few minutes.

A panel of experts during the European Vascular Course estimated that more than
one million patients will be treated worldwide in 2011 with EVLA.

Because of the continuous promotion of the industry and publication bias it
seems that EVLA will become the new 'gold standard' for the treatment of the
great saphenous vein.

During EVLA, carbonisation of blood and tissue will occur. Patients recognize
this as a taste and smell of 'burned tissue'. This is a systemic effect of
carbonized blood passing the nose and tongue mucous membranes.

During (extreme) heat of proteins and/or sugars, polycyclic aromatic
hydrocarbons (PAH), heterocyclic amines (HCA) and acrylamide will be formed in
a probably high concentration.

Proven human carcinogenic in the group of PAH is benzo[a]pyrene. Possible human
carcinogenic in the group HCA is 2-amino-1-methyl- 6-phenylimidazole [4,5-b]
pyridine (PhIP). Acrylamide is possible carcinogenic in humans in high
concentrations.
All these substances are carcinogenic in animals,
Maximal Allowable Concentrations (MAC) are defined by the World Health
Organization of these substances. It is probably safe to state that the MAC in
the human (milieu interne) should not exceed the levels of the environment
(milieu externe)

This study will determine the concentration of benzo[a]pyrene before and after
EVLA.

This prospective study will be performed in the Sint Franciscus Gasthuis
Rotterdam in collaboration with the University of Wageningen.
The aim of this study is to determine the concentration of benzo[a]pyrene
before and after EVLA.

A total of 20 patients will be included in this study (10 smokers and 10 non
smokers)
It is known that smokers already have elevated concentrations of
benzo[a]pyrene. During the first contact by telephone, patients will get study
information and a time span of 2 days to determine if they want to participate
in the study. The study will be discussed on the outpatient clinic.

Patients will have a medical history taken, physicial examination and a duplex
ultrasound.Patients with venous disease and complaints in combination with a
duplex proven incompetence of the great saphenous vein will be treated with
EVLA.

In all study patients, a blood sample will be collected before and after EVLA
(total 2 blood samples). Patients will be further treated according to the EVLA
protocol (stockings / paracetamol and a visit at the outpatient clinic after
two weeks)

The blood samples will be coded and send to a specialized laboratory at the
University of Wageningen.

An independent surgeon (H. Strijdhorst) will be present for further study
questions.

The concentration of benzo[a]pyrene will be determined for all study patients
before and after EVLA.

There is no need for follow-up.

If extreme concentrations of benzo[a]pyrene occur during EVLA, an international
warning should be issued and EVLA treatment should be abandoned.
There are alternatives for the treatment of the great saphenous vein in which
lower temperatures (around 100 degreed Celsius) can be used, thereby decreasing
or eliminating blood carbonization.

none