Functional outcome of radiotherapy and laser surgery in early laryngeal carcinoma: a strategy study

The main treatment modalities for early glottic carcinoma are radiotherapy and
carbon dioxide endoscopic laser surgery (henceforth laser surgery). According
to the national Dutch Guideline *Larynxcarcinoom* 2008, laser surgery is the
treatment of choice for T1a superficial midcord lesions whereas radiotherapy is
the gold standard for extended T1 and T2 glottic carcinomas at present. Laser
surgery does have several advantages: Extra treatment steps are available in
the case of recurrence, i.e. multiple laser or radiotherapy, leading to higher
larynx preservation. It is also cheaper, and the treatment duration is shorter
than radiotherapy. With regard to local control and laryngectomy rate in T1 and
T2 glottic carcinomas, available studies provide evidence that laser is at
least comparable to, and probably better than radiotherapy. However, due to a
lack of comparative data concerning functional outcome (i.e. voice), the two
treatments cannot be properly compared for extended T1 and limited T2 glottic
carcinomas at the moment. Surgeons are not prepared to enter patients into a
randomized controlled trial, because it is as yet uncertain how voice quality
and voice function will be affected when these extended glottic tumors are
treated with laser surgery. Preferred treatment strategy for extended T1 and
limited T2 tumors can only be decided when the frequency and severity of
functional toxicities have been determined and when it is known how patients
value possible functional toxicities.

Determine the longitudinal functional toxicity profiles after laser surgery and
after radiotherapy for extended T1 and limited T2 glottic carcinomas by
evaluating all voice and swallowing related aspects.

Prospective cohort study that has the character of an exploratory pilot study.
The study has a follow-up of 2 years; measurements are taken once pre-treatment
and five times post-treatment during routine clinical follow-up visits.

Either laser surgery or radiotherapy according to the patient*s preference. For
treatment with laser surgery, the tumor is assessed by the ENT surgeon during
endoscopy. If the tumor meets the inclusion criteria specified for this study,
and the patient has elected to be treated with laser surgery, this will take
place during the same session. If laser surgery is not feasible, either because
the tumor does not meet the inclusion criteria, or exposure to surgical fields
is limited, the subject will be treated according to the national guideline. In
most cases this will mean allocation to radiotherapy.

Burden: The burden for the individual patient is the extra time it takes (50
minutes) to complete the functional protocol (including questionnaires).
Because the functional protocol is always combined with routine follow-ups,
there will not be extra site visits.
Risks: Laser surgery and radiotherapy are both established routine treatment
modalities. For the extended tumors, the extra risk of laser surgery will be
the larger resection defect that may result in poor voice quality and function.
However, this study aims at determining the frequency and severity of this
risk. This study might also reveal that voice and swallowing is more of a risk
after radiotherapy than has been documented before.
Benefit for the patient: Treatment choice according to preference. Laser
surgery comprises shorter treatment with extra treatment options (a second
laser resection or radiotherapy) in the case of recurrence. Radiotherapy is
expected to have no, or only a mild effect on the voice compared to laser
surgery.
Benefits in general: The relative benefits of the two treatment modalities can
be compared using the outcomes of this study. Clinicians can also begin to gain
insight into the trade-off between oncological and functional outcome. This may
eventually lead to more individually tailored intervention. Ultimately, an
acceptable toxicity profile and higher probability of larynx preservation may
change laser surgery from alternative, to primary treatment for extended T1 and
limited T2 glottic tumors. This in turn will be cost-saving as laser surgery is
shorter in duration and cheaper than radiotherapy.