AM ER IC AN JOURNAL OF OT OLA RYNGOLOGY–H E A D A N D NE CK M E D ICI N E AN D S U RGE RY 3 6 (2 0 1 5) 4 60 –4 6 2
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Squamous cell carcinoma in a thyroglossal duct cyst: A case report with review of the literature☆ Suparna Shah, MBA a , Sameep Kadakia, MD b,⁎, Azita Khorsandi, MD c , Austin Andersen, MD d , Codrin Iacob, MD d , Edward Shin, MD b a
New York Medical College, Valhalla, NY Department of Otolaryngology-Head and Neck Surgery, The New York Eye and Ear Infirmary of Mount Sinai, New York, NY c Department of Head and Neck Radiology, The New York Eye and Ear Infirmary of Mount Sinai, New York, NY d Department of Head and Neck Pathology, The New York Eye and Ear Infirmary of Mount Sinai, New York, NY b
ARTI CLE I NFO
A BS TRACT
Carcinoma arising within a thyroglossal duct cyst (TGDC) is exceedingly uncommon,
Received 29 November 2014
occurring in about 1% of TGDC (Chrisoulidou et al., 2013 ). Since the first description of TGDC carcinoma in 1911 by Brentano, approximately 200 cases have been reported in the world literature, mostly as single case reports making its true incidence difficult to determine (Hanna, 1996 ,). There are numerous reports in the literature of papillary and follicular TGDC carcinoma, but only limited reports of squamous cell carcinoma. In order for a lesion to qualify as squamous cell carcinoma of a TGDC, the lesion must arise from the epithelial lining. Recognition and understanding of this entity are important in staging and planning of treatment. Exclusion of primary squamous cell carcinoma arising from an adjacent structure or metastatic central compartment nodal disease is important in the evaluation for diagnosis to be confirmed. A thorough work up should be undertaken to exclude other primary malignancies that may have metastasized. We present a unique case of squamous cell carcinoma, along with supporting pathology and radiology imaging. We then review this rare entity and provide some insight into the diagnosis and management. © 2015 Elsevier Inc. All rights reserved.
A 47-year-old male smoker presented with a 6-month history of a right-sided neck mass with associated pain, hoarseness, and productive cough. Significant past medical history included an unknown thyroid disorder, Chronic Obstructive Pulmonary Disorder (COPD), and Obstructive Sleep Apnea
(OSA). On examination, he had a mildly tender, soft, right neck mass that elevated with swallowing. The thyroid gland was midline and non-enlarged, and there was no evidence of cervical lymphadenopathy. Computed tomography (CT) of the neck with contrast revealed an 8 × 8 × 5 cm cystic lesion with thick septations and solid areas of enhancement arising from the thyroid notch and extending to the midline tongue base.
No financial disclosures or conflicts of interest. ⁎ Corresponding author at: Department of Otolaryngology-Head and Neck Surgery, The New York Eye and Ear Infirmary of Mount Sinai, New York, NY. E-mail addresses: [email protected]
(S. Shah), [email protected]
(S. Kadakia), [email protected]
(A. Khorsandi), [email protected]
(A. Andersen), [email protected]
(C. Iacob), [email protected]
(E. Shin). http://dx.doi.org/10.1016/j.amjoto.2015.01.012 0196-0709/© 2015 Elsevier Inc. All rights reserved.
AM ER IC AN JOURNAL OF OT OLARYNGOLOGY–H E A D A N D NE CK M E D IC IN E A ND S U RGE RY 3 6 (2 0 1 5) 4 60–4 6 2
This lesion was deep to the strap muscles. These findings are shown below in Figs. 1 and 2. Cytological sampling of the neck mass revealed benign and enucleated squamous cells in a background of proteinaceous debris. Based on these findings, thyroglossal duct cyst was the suspected diagnosis and the decision to perform a Sistrunk procedure was made. During the resection, the mass was punctured and thick yellow fluid was noted to extrude from it. At the lower extent of the resection, it was noted that the mass was abutting the thyroid gland. The mass was carefully dissected from the thyroid gland and the thyroid gland was left intact. The thyroid gland appeared normal, and no suspicious lymph nodes were seen. The cyst and cyst contents were sent for pathological review. The patient tolerated the procedure well with no post-operative complications. Histologic analysis of the lesion showed numerous malignant squamous cells in the specimen with frequent mitotic figures as shown in Figs. 3 and 4. The diagnosis of squamous cell carcinoma was confirmed, and the patient was sent for PET/CT scan, which did not reveal regional or distant metastatic disease. The patient was postoperatively sent for evaluation by radiation oncology and medical oncology for chemotherapy and radiation. The patient received weekly cisplatin, as well as 6600 Gy of external beam radiation divided into 33 fractions. Given the likely descent from the tongue base, this region was included in the radiation field. Currently, the patient is due for a three month post-treatment follow-up during which repeat imaging will be ordered as well.
TGDC represents the most common congenital neck mass and is found in approximately 7% of the population [3,4].
Fig. 1 – Axial CT of the soft tissue neck with intravenous contrast demonstrates multiseptated cystic type lesion centered at the thyroid notch. Thick nodular septation of this lesion is noted. Image provided courtesy of Dr. Azita Khorsandi MD, Department of neuroradiology at New York Eye and Ear Infirmary.
Fig. 2 – Sagittal CT of the soft tissue neck with intravenous contrast demonstrates multiseptated cystic type lesion centered at the thyroid notch. Thick nodular septation of this lesion is noted. Image provided courtesy of Dr. Azita Khorsandi MD, Department of neuroradiology at New York Eye and Ear Infirmary.
During development, the thyroid descends from the foramen cecum of the tongue to its location in the anterior neck. A failure of the associated tract to involute gives rise to thyrogossal duct cysts. A TGDC can present at any age and patients typically present with a slow growing painless mass that is midline and moves with swallowing and tongue protrusion . Although typically benign, TGDC can harbor carcinoma. Any TGDC that is firm, fixed, or irregular should be evaluated for malignancy. The median age of presentation is reported to be in the 4th decade of life, with women more commonly affected than men . Most TGDC carcinomas are found incidentally on postoperative pathological examination . The incidence of TGDC carcinomas is roughly 1% of all TGDCs
Fig. 3 – 40× magnification of H&E stain of tumor specimen showing numerous mitotic figures in tumor. Original image provided courtesy of Austin Anderson MD and Iacob Codrin MD, Department of Pathology New York Eye and Ear Infirmary.
AM ER IC AN JOURNAL OF OT OLA RYNGOLOGY–H E A D A N D NE CK M E D ICI N E AN D S U RGE RY 3 6 (2 0 1 5) 4 60 –4 6 2
Fig. 4 – 20 × magnification of H&E stain of transition between columnar epithelial to malignant squamous cells. Original image provided courtesy of Austin Anderson MD and Iacob Codrin MD, Department of Pathology New York Eye and Ear Infirmary.
and greater than 90% have been described as well differentiated papillary carcinomas . However, 6% of specimens show squamous cell carcinoma . To date, 22 cases have been detailed in the literature with only 11 patients reported to have adequate follow up information . Due to the small number of reported cases, it is difficult to draw conclusions regarding management of this rare lesion and as such, this remains an area of controversy. The origin of thyroglossal duct cyst (TGDC) carcinoma is important since it has implications in disease management. Two theories currently exist for the origin of papillary TGDC carcinoma. One theory states that it arises de novo from native thyroid tissue found within the walls of the thyroglossal duct cyst while another theory proposes that TGDC carcinoma is metastatic disease from carcinoma originating in the thyroid gland . As most TGDCs contain normal thyroid tissue and most TGDCs have been papillary or follicular, the former theory is more widely supported than the latter. The high incidence of concurrent thyroid carcinoma in patients with TGDC carcinoma provides support to the latter theory and suggests that the fibrous tract may itself be a route of spread . As medullary thyroid cancer arises from parafollicular cells not typically found in ectopic thyroid tissue, this entity has not been described in TGDC malignancy . Although rare, strict criteria for the diagnosis of TGDC squamous cell carcinoma were outlined by Mobini et al. . The criteria suggest that the TGDC should have a midline location and have an epithelial lining with adjacent normal thyroid follicles. Squamous cell carcinoma should arise directly from the cyst wall and a transition between the epithelium of the duct or cyst and the tumor mass should exist . Prior to applying this criteria however, a thorough workup should be conducted to exclude the possibility of primary squamous cell carcinoma of the tongue base extending to the anterior neck or metastatic central compartment nodal disease which could both potentially mimic this entity on imaging.
Given the dearth of information, management is often controversial especially when addressing the clinically normal thyroid gland . Excision of the TGDC is well accepted, but whether a concomitant thyroidectomy should be performed can be a challenge for surgeons. Carcinoma of the thyroid gland is found in 27% to 56% of patients diagnosed with TGDC carcinoma . As this range has considerably variability, there is no agreement on the role of a total thyroidectomy . Other controversies include management of lymph nodes, the role of thyroid suppression therapy, and radioactive iodine therapy . Patients with more extensive disease may require wider excision, and those with clinically positive cervical adenopathy may required neck dissection as well. Prophylactic neck dissection in the clinically negative neck is not advised . Strict follow up with imaging and laboratory studies to detect malignant changes is a crucial part of treatment . Some advocate the use of thyroid suppression therapy or radioactive iodine therapy to make follow up to detect malignant recurrence more feasible since a thyroglobulin assay could be used as a reliable marker . Postoperative radiation may be indicated for larger lesions, but has not been clearly defined . In our case, the patient was sent for postoperative radiation because an oncologic resection was not performed as the disease process was presumed to be a benign thyroglossal duct cyst. As such, when the lesion was found to be cancerous and margins positive, radiation therapy was given. As mentioned earlier, no clear guidelines exist regarding criteria for post-operative radiation; however, our institution recommends radiation for patients who have not had an oncologic resection and for those with positive margins. The prognosis of patients with squamous cell carcinoma remains unpredictable. The more common papillary carcinoma has a good prognosis with complete excision being curative. If the lesion extends beyond the cyst walls or complete excision is not performed, local recurrence is likely. Close long-term follow up and a multidisciplinary approach are essential in all cases . Further research and clinical trials are required to better delineate management guidelines for this rare and controversial malignancy.
 Chrisoulidou A, Iliadou P, Doumala E, et al. Thyroglossal duct cyst carcinomas: is there a need for thyroidectomy? Hormones (Athens) 2013;12:522–8.  Hanna E. Squamous cell carcinoma in a thyroglossal duct cyst (TGDC): clinical presentation, diagnosis, and management. Am J Otolaryngol 1996;17:353–7.  Kinoshita N, Abe K, Sainoo Y, et al. Adenosquamous carcinoma arising in a thyroglossal duct cyst: report of a case. Surg Today 2011;41:533–6.  Jang DW, Sikora AG, Leytin A. Thyroglossal duct cyst carcinoma: case report and review of the literature. Ear Nose Throat J 2013;92:E12–4.  Motamed M, Mcglashan JA. Thyroglossal duct carcinoma. Curr Opin Otolaryngol Head Neck Surg 2004;12:106–9.  Mobini J, Krouse TB, Klinghoffer JF. Squamous cell carcinoma arising in a thyroglossal duct cyst. Am Surg 1974;40:290–4.