During her presentation at the 2007 Combined Otolaryngology Spring Meeting in San Diego, Dana M. Hartl, MD, PhD, from the Department of Otolaryngology Head and Neck Surgery at the Institut Gustave Roussy in France, described her findings from a retrospective, bi-institutional study designed to review the results of a large series of patients with early glottic squamous cell carcinoma treated with curative intent by transoral laser resection.
Explore this issue:March 2008
We also sought to compare these results with the pathological assessment of the resection margins, involvement of the anterior commissure, and the extent of the cordectomy, said Dr. Hartl, whose study was published in the Annals of Otology, Rhinology, and Laryngology.
Since the 1990s, transoral laser resection has become a standard treatment for early glottic cancer and a valid alternative to radiation therapy or external partial laryngectomy in terms of oncologic results. Studies have shown that transoral laser resection provides greater than 90% local control and laryngeal preservation for early glottic cancer.
According to Dr. Hartl, the use of this technique requires specific equipment and instrumentation, adequate exposure of the larynx, and specific surgical training and experience. Pathologists analyzing surgical specimens after laser resection also require training and experience because of the small resection specimens and the peripheral coagulation effect (0.5 mm) of laser on resection margins.
Details of the Study
Of 142 patients, 79 were selected for this study, based on their pT stage, the availability of information regarding resection margins, the absence of adjuvant radiation therapy, and evidence of follow-up for at least two years.
Tumors were classified pTis (n = 21), pT1a (n = 51), or pT1b (n = 7) and were treated by cordectomy types I (23%), II (30%), III (27%), IV (6%), and V (14%), based on the European Laryngological Society’s classifications of endoscopic laser cordectomies. Type I is a subepithelial resection (respecting the vocal ligament). Type II is a subligamental resection. Type III is intramuscular (partial resection of the vocalis muscle). Type IV is a total resection of the vocal fold. Type V is an extended cordectomy with subtypes indicating extension to include the anterior commissure (type Va), the arytenoid cartilage (type Vb), the false vocal fold (type Vc), or the subglottis (type Vd).
Surgeons performed the cordectomies with en bloc resection; pathologists considered the resection margins to be: free (tumor at least 2 mm from the edge of the specimen), positive (tumor at the margin of the specimen), or suspicious (tumor less than 2 mm from the edge of the specimen).
The average follow-up was 56 months. The overall five-year actuarial recurrence-free survival rate was 89%, and the five-year actuarial disease-specific survival rate was 97.3%. Eleven local recurrences occurred; seven were treated by another laser resection, one by radiation therapy, one by supracricoid partial laryngectomy, and two by total laryngectomy.