1

Introduction

Routine ipsilateral hemithyroidectomy has long been considered as the standard surgical practice for all patients undergoing total laryngectomy . However, hemithyroidectomy has been reported to be the most important factor for the development of posttreatment hypothyroidism in these patients .

There are numerous studies investigating thyroid gland invasion (TGI) in laryngeal cancer, and the common conclusion of these studies is that tumors with subglottic involvement show a greater tendency for TGI over others . The incidence of TGI in laryngopharyngeal cancer has been reported to be between 2% and 14% . This incidence has come from the studies in which patients with pyriform sinus cancer constituted only a small portion of the study groups. Hence, data about TGI by pyriform sinus cancer are limited in the literature.

At our institution, ipsilateral hemithyroidectomy has been routinely performed in all patients undergoing laryngopharyngectomy for pyriform sinus cancer. The goals of this study are to determine the incidence of TGI by pyriform sinus cancer in our cohort of patients and to revisit the concept of routine ipsilateral hemithyroidectomy in the treatment of pyriform sinus cancer.

2

Patients and Methods

A retrospective analysis of all patients with pyriform sinus cancer who underwent laryngectomy with ipsilateral hemithyroidectomy between January 1999 and December 2011 at a single institution (Wayne State University/Karmanos Cancer Institute, Detroit, MI) was conducted for this study. Patients with a history of primary thyroid cancer or previous thyroidectomy were excluded. This study was approved by the institutional review board of Wayne State University. The age and sex of patients and the stage of cancer were obtained from the medical charts. Reports of preoperative computed tomographic (CT) scans of the neck and the operative notes were reviewed to find out any evidence of TGI by pyriform sinus cancer with either imaging or clinical assessment. Histopathologic reports of surgical specimens were reviewed to note the presence or absence of TGI by the tumor.

2

Patients and Methods

A retrospective analysis of all patients with pyriform sinus cancer who underwent laryngectomy with ipsilateral hemithyroidectomy between January 1999 and December 2011 at a single institution (Wayne State University/Karmanos Cancer Institute, Detroit, MI) was conducted for this study. Patients with a history of primary thyroid cancer or previous thyroidectomy were excluded. This study was approved by the institutional review board of Wayne State University. The age and sex of patients and the stage of cancer were obtained from the medical charts. Reports of preoperative computed tomographic (CT) scans of the neck and the operative notes were reviewed to find out any evidence of TGI by pyriform sinus cancer with either imaging or clinical assessment. Histopathologic reports of surgical specimens were reviewed to note the presence or absence of TGI by the tumor.

3

Results

There were 19 male and 8 female patients with ages ranging from 44 to 79 (mean, 59.9) years. Eighty-five percent of our study group had advanced-stage disease: only 4 patients had stage 2 disease, whereas 8 had stage 3 disease and 5 had stage 4 disease. Preoperative CT scans of the neck were available in 23 patients. Preoperative CT scans of the neck have been assessed by dedicated neuroradiologists at our institution. Extralaryngeal spread of tumor with thyroid cartilage invasion was noted in the CT scans of 5 patients. However, there was no radiologic evidence of TGI by the tumor in any scan. Detailed operative reports of 26 patients were available, whereas some details were missing in the surgical notes of 1 patient. No gross TGI was appreciated in any patient during surgery. Histologic evaluation of surgical specimens stained with hematoxylin-eosin was undertaken by dedicated head and neck oncology pathologists at our institution. No histologic evidence of TGI was found in any specimen.