Transoral laser microsurgery for the treatment of oropharyngeal cancer: the Dalhousie University experience

Between 2002 and 2014, 39 patients (31 males and 8 females) with oropharyngeal carcinoma
underwent TLM resection (Table 1). The mean age of the cohort at the time of diagnosis was 59.6 years (range 32–80).
Twenty-eight (72 %) patients had primary carcinoma, 9 (23 %) were RT/CRT failures,
and 2 (5 %) had second primaries following previous RT/CRT. Three patients had stage
I disease, 8 stage II, 5 stage III, and 23 stage IV. HPV status was available for
26 patients, of which 23 (88 %) had HPV positive disease. The mean time of follow-up
was 23 months. Among patients with primary OSCC, 21 patients received adjuvant therapy;
14 received radiation therapy and seven received chemoradiation. Twenty-nine (75 %)
patients underwent concurrent neck dissections at the time of TLM resection. The average
length of hospital stay was 3.8 days (range 2–10 days).

Table 1. Patient characteristics (n?=?39)

Three patients developed complications following TLM resection. One patient experienced
significant postoperative bleeding requiring a blood transfusion 14 days postoperatively.
The patient was taken to the OR for exploration, but no active site of bleeding could
be identified. The bleeding resolved spontaneously and was later determined to be
caused from a longstanding gastric ulcer. Two patients developed cardiovascular complications.
One patient experienced a myocardial infarction following TLM reresection of a positive
margin and another patient developed a pulmonary embolism 3 days postoperatively.
All patients recovered from their complications.

Two patients required a gastrostomy tube (G-tube) postoperatively following initial
TLM resection. One patient required a temporary G-tube (2 months) following TLM resection
for swallowing difficulties. The other patient required a long-term G-tube following
postoperative CRT for a close margin. One and two year G-tube rates following initial
TLM resection were 3 and 0 %, respectively. Three patients required G-tubes following
salvage therapy for recurrences. One patient required a temporary G-tube (6 months)
following salvage radiation therapy for a local recurrence. Another patient, who underwent
a radical neck dissection following recurrence of a neck mass, subsequently developed
a hematoma postoperatively and required a tracheostomy and G-tube for breathing and
swallowing difficulties. Finally, one patient who ultimately underwent a total laryngopharyngectomy
for new primary disease, required a G-tube postoperatively after the development of
a tracheoesophageal fistula. Of note, one patient developed mild velopharyngeal insufficiency
postoperatively that improved overtime without intervention and another patient, who
was a previous CRT failure with a preoperative G-tube, was able to have their G-tube
successfully removed following TLM resection.

Five patients had temporary tracheostomies following TLM. Initially, this was done
for all TLM resections for anticipated postoperative swelling. This practice was stopped
after it was seen that most patients had minimal swelling postoperatively. All five
patients had their tracheostomies removed prior to discharge. One and two year tracheostomy
rates were 0 %.

There were eight cases of recurrence following TLM, including five local recurrences
(two of which also had regional recurrence), two regional recurrences, and one case
of metastasis. There was also one case of a new primary in a patient with a right
tonsil OSCC who went on to develop a left piriform sinus OSCC following TLM. Recurrence
was more common among RT/CRT failures compared to patients with new primary oropharyngeal
carcinoma. Kaplan-Meier estimates of 36-month LC for new primary oropharyngeal carcinoma
was 85.5 % (SE 10.6 %) compared to 66.76 % (SE 15.7 %) for RT/CRT failures (Fig. 1).

Fig. 1. Kaplan-Meier estimates of 36-month local control

During follow-up, seven patients died from their disease. All four RT/CRT failures
who developed recurrence died from their disease. Two of four patients with primary
oropharyngeal carcinoma who developed recurrence died from their disease. One patient,
who received TLM for a second primary following previous CRT, developed a new primary
following TLM and despite undergoing a total laryngopharyngectomy, ultimately developed
metastatic disease and died from their disease. Kaplan-Meier estimates of 36-month
DSS and DFS for primary oropharyngeal carcinoma were 85.7 % (SE 13.2 %) and 77.7 %
(SE 12.5 %) compared to 55.6 % (SE 16.6 %) and 55.6 % (SE 16.6 %) for RT/CRT failures
(Fig. 2).

Fig. 2. Kaplan-Meier estimates of 36-month disease specific survival and disease free survival

Adjuvant therapy was administered to 21 of 28 patients with new primary OSCC (Table 2). Fourteen patients received radiation therapy and seven received chemoradiation.
The remaining seven patients received no postoperative therapy. Among patients who
did not receive postoperative therapy, three developed recurrence. All three patients
had stage III/IV oropharyngeal carcinoma and of these, two patients refused adjuvant
therapy for personal reasons and one was not a candidate because of comorbid health
conditions. No patients with stage I/II disease treated with TLM monotherapy developed
recurrence. Among patients who received adjuvant therapy, one patient developed metastatic
disease.

Table 2. Adjuvant therapy for new primary OSCC following TLM resection (n?=?28)

Salvage therapy was carried out in two of four cases of recurrence among patients
with primary oropharyngeal carcinoma. One case of local recurrence was salvaged with
radiation therapy and the patient currently remains disease free. The other case of
regional recurrence was salvaged with a selective neck dissection, but unfortunately
the patient went on to develop metastatic disease and died from their disease. Among
the other two cases of recurrence, one patient developed metastatic disease for which
further therapy was not indicated and the other patient refused further treatment
after local recurrence. As previously mentioned, a total laryngopharyngectomy was
carried out in a patient who developed a new primary following TLM, but the patient
ultimately developed metastatic disease and died from their disease. No previous RT/CRT
failures who developed recurrence received salvage therapy.

Four patients (10 %) had positive margins and one patient (3 %) had a close margin
at the primary site following initial TLM resection (Table 3). Four patients, including the patient who had a close margin, had primary OSCCs
and one patient was a previous RT failure. The previous RT failure subsequently underwent
TLM reresection, but ultimately developed locoregional recurrence and died from their
disease. Among the four patients with primary OSCCs, three received postoperative
chemoradiation and one received postoperative radiation. Two of the three patients
who received postoperative chemoradiation stopped their chemotherapy early because
of side-effects. Of the patients who received adjuvant therapy, one developed metastatic
disease and died from their disease. The other three patients remain disease free.

Table 3. Intraoperative disease control

Twenty three patients had HPV positive disease and three patients had HPV negative
disease. HPV status could not be determined in 13 patients. Among HPV positive patients,
two developed recurrence. One patient developed a local recurrence after initially
refusing adjuvant radiation therapy and is currently awaiting further management.
The other patient developed metastatic disease and died from their disease. Among
the three patients with HPV negative disease, two developed recurrence. One patient
developed recurrent regional disease and died from their disease. The other patient
developed local recurrence and after receiving salvage radiation therapy, remains
disease free.