Recurrent dysphagia in a patient with invasive papillary thyroid carcinoma

Issue: July 2010

ByStephanie L. Lee, MD, PhD, ECNU

Four years ago, a 45-year-old woman was seen in the endocrine clinic complaining of 2 years of a hoarse voice and progressive dysphagia to solid foods with a â€œnormalâ€� nuclear thyroid scan and a 3.5-cm thyroid mass on a CT scan of the neck, as described in a previous Imaging Analysis column.

Stephanie L. Lee, MD, PhD
Stephanie L. Lee

Before her thyroidectomy, a barium swallow showed a smooth extrinsic compression of the esophagus (figure 1A) consistent with compression of the esophagus by the thyroid mass. In the operating room, a 5-cm Ã— 4-cm Ã— 3-cm mass was found in the paratracheal space and was peeled off with great difficulty by sharp dissection from the tracheal and esophagus. To achieve a negative surgical margin, the longitudinal muscle of the esophagus was removed with the tumor. There was direct invasion of the skeletal muscle of the strap muscles and the right recurrent laryngeal nerve with one lymph node in level VI (paratracheal) positive for papillary thyroid carcinoma.

She received 153 mCi of I-131 with a post-therapy scan showing multifocal uptake only in the thyroid bed. She has remained disease-free with negative evaluations for recurrent tumor by neck ultrasound exams and recombinant human thyroid-stimulating hormone stimulated I-123 whole-body scan.

Elevated thyroglobulin antibody titers interfere with the thyroglobulin immunometric assay and prevented using her serum thyroglobulin levels as a tumor marker. Her thyroglobulin antibody titers have been falling from 2,784 IU/mL to 20.7 IU/mL in the past 4 years, suggesting ablation of her tumor.

Figure 1. CT scan of the neck with contrast. A. Coronal image showing the esophageal diverticulum to the right of the esophagus and trachea (blue arrow). B. Axial image showing the diverticulum posterior to the trachea (blue arrow).

Photo courtesy of: Stephanie L. Lee, MD, PhD

Possible recurrent tumor

About 2.5 years after her surgery, the patient returned to the endocrine clinic complaining of recurrent solid dysphagia and concerns for recurrent thyroid cancer. Her neck ultrasound in the endocrine clinic did not reveal any masses. A repeat barium swallow was performed that demonstrated a right lateral outpouching from the levels of the C6 through T1 vertebral bodies consistent with a diverticulum (figure 2B), rather than extrinsic compression. The walls were smooth and no extravasation of contrast was seen. There was significant retained barium in the esophageal diverticulum (figure 2C).

A CT scan demonstrated a large esophageal outpouching just inferior to the region of the thyroid bed at the C7 level (figure 2). A fiberoptic endoscopy was performed that revealed a broad-based diverticulum on the right side of the esophagus below the cricopharyngeus muscle. A recombinant human TSH stimulated I-123 whole-body scan was negative for abnormal I-123 radioactive iodine uptake.

Patients with thyroid cancer with macroscopic invasion outside the thyroid are at moderate risk for tumor recurrence. Although this patient is in the moderate risk category, her recurrent dysphagia may not indicate recurrent tumor. In this case, to achieve a negative surgical margin, the outer layer â€” the external longitudinal muscle layer â€” on the right side of the esophagus had to be removed and resulted in a broad-based esophageal diverticulum.

Figure 2. Barium swallow. A. Before thyroidectomy showing smooth indentation of the esophagus by the large thyroid carcinoma causing solid food dysphagia (red arrow). B. Two-and-a-half years after thyroid surgery. Bolus of contrast shows broad-based diverticulum along the right side of the esophagus (blue arrow) approximately at the previous site of the tumor obstruction. C. After barium bolus passes the diverticulum, barium is retained in the diverticulum (green arrow).

Risk for diverticulum rupture

Care should be taken interpreting radioiodine whole-body scans because esophageal diverticulum and hiatal hernia may result in false positive scans caused by focal retention of radioiodine that mimics metastatic thyroid cancer. Esophageal diverticulum has been interpreted as thyroid nodules on ultrasound and has undergone fine needle aspiration biopsy. The differential for a mass in level VI or recurrent dysphagia after thyroidectomy, especially if the tumor required dissection from the esophagus, should include a paraesophageal diverticulum.

Beyond her current complaints of halitosis and dysphagia, the patient is at risk for rupture of the diverticulum with infection of the deep structures of the neck. The otolaryngology surgeon felt that there should be sufficient paraesophageal scar tissue and that rupture was of low probability.

The patient was given two options: observation or resection of the diverticulum with a total esophagectomy and gastric pull-up or a pectoralis flap reconstruction. The patient opted for observation and is scheduled for another CT scan of the neck with contrast and a modified barium swallow to assess for interval change of the diverticulum.

Stephanie L. Lee, MD, PhD, is associate professor of medicine and associate chief in the section of endocrinology, diabetes and nutrition at Boston Medical Center.

For more information:

Lee SL. Endocrine Today. 2008;6:8.

Rashid K. Clin Nucl Med. 2006;31:405-408.

Walts AE. Diagn Cytopathol. 2006;34:843-845.

Willis LL. Clin Nucl Med. 1993;18:961-963.