Metastatic merkel cell carcinoma to the thyroid gland: Case report and review of the literature.

BACKGROUND: Merkel cell carcinoma (MCC) is an aggressive and rare neuroendocrine tumor, accounting for less than 1% of skin cancers. Metastasis primarily manifests in the cervical lymph nodes but rarely affect the thyroid. METHODS: We report a case of primary head and neck cutaneous MCC with metastasis to the thyroid gland. A review of the literature of MCC with thyroid metastasis was conducted. RESULTS: We identified five cases of MCC with thyroid metastasis. Primary sites included the distal upper and lower extremities, axilla, buttock, and groin. Treatment courses varied including thyroidectomy, immunotherapy, and expectant palliative measures. Time from initial diagnosis to thyroid metastasis ranged from four months to four years. Tissue diagnosis was achieved in 5 of 6 cases. CONCLUSIONS: MCC with thyroid metastasis is rare and likely represents aggressive disease. Despite advances in treatment and surveillance, outcomes for MCC remain poor. Ongoing research may establish predictors for treatment response.

Thyroid cancer necrosis not evident on imaging: A cautionary case series on poorly differentiated thyroid carcinoma diagnosed only on final pathology.

OBJECTIVE: Poorly-differentiated thyroid cancer (PDTC) is a highly aggressive malignancy which is recently defined and understudied in the radiologic literature. Necrosis is a key histopathologic criterion for the diagnosis of PDTC. We illustrate the current difficulty in accurate identification of histopathologic necrosis on preoperative imaging. METHODS: A series of seven patients with the final diagnosis of PDTC from our institution were identified. Multimodality preoperative imaging was analyzed by two head and neck radiologists. Final pathology reports were queried confirming histopathologic evidence of necrosis. RESULTS: Patients presented with a wide range of preoperative imaging features. A consistent imaging appearance confirming necrosis was not identified. All patients were subsequently upstaged to PDTC following final pathological analysis. CONCLUSION: A lack of definitive evidence of necrosis on preoperative imaging does not exclude the possibility of PDTC. We demonstrate the need for further research to establish a clear methodology for the preoperative diagnosis of PDTC.

Extratumoral invasion: A unique phenomenon of aggressive recurrent oropharyngeal squamous cell carcinoma.

BACKGROUND: Oropharyngeal squamous carcinomas cause significant morbidity and mortality. Poor prognosticators include lymphovascular and perineural invasion. Extratumoral phenotypes of these histologic findings confer worse prognoses. METHODS: We report eight cases of recurrent oropharyngeal cancer with diffuse extratumoral lymphovascular invasion (ELVI) or extratumoral perineural invasion (EPNI) and review the existing literature. RESULTS: On salvage resection for recurrence following primary radiation or chemoradiation, six patients manifested ELVI and two showed EPNI. These patterns conferred difficulty with complete surgical clearance; final pathologic analysis demonstrated positive margins for all eight patients. The six patients with ELVI were p16+ and the two with EPNI were p16-. Currently, two patients are deceased and six patients are alive at an average follow-up of 17.4 months. Of the six living patients, 2 have a new recurrence and are in hospice while 4 have no evidence of disease. CONCLUSIONS: ELVI and EPNI have received little consideration in the literature as unique histopathologic features of oropharyngeal squamous carcinoma. We present the first series on these adverse extratumoral features in recurrent disease. We call attention to these unique histologic features in the setting of recurrent oropharyngeal cancer to encourage others to track the results of therapeutic intervention and to identify successful strategies for treatment.

The anatomical basis for preserving the blood supply to the parathyroids during thyroid surgery, and a review of current technologic advances.

BACKGROUND: Devascularization of the parathyroid glands is generally accepted as the most common mechanism for iatrogenic hypocalcemia, a frequently seen complication of both total and completion thyroidectomy procedures. Much has been written about iatrogenic hypoparathyroidism, but few papers have precisely delineated the arterial supply of the parathyroid glands and the common anatomical variations that may impact parathyroid preservation during thyroid surgery. METHODS: We offer an illustrated review and discussion of the only two anatomic studies published in the medical literature focusing on parathyroid vasculature. In addition, we examine current techniques of parathyroid identification, preservation, and classification. FINDINGS: A surgical technique that preserves the parathyroid arteries is vital to preserving the viability of the parathyroid gland(s) during thyroid surgery. In 1907, Halsted and Evans described a technique of ligating the distal branches of the thyroid arteries beyond the origin of the parathyroid arteries, a technique termed ultra-ligation. In 1982, Flament et al.. reported three distinct anatomical variations of the parathyroid arteries which place the parathyroid blood supply at risk for devascularization during thyroid surgery. Our review also highlights novel techniques that aid surgeons in identification and assessment of the parathyroid glands. CONCLUSIONS: Recognition of the variations of parathyroid anatomy and their potential to lead to devascularization aids thyroid surgeons in their pursuit of parathyroid preservation. An awareness of the variety of novel parathyroid identification and preservation techniques can assist surgeons to achieve this goal.

Reconstruction of the external auditory canal: The tragal flap revisited and review of contemporary reconstructive techniques.

BACKGROUND: Primary malignancies arising in the external auditory canal (EAC) are rare and usually are treated surgically. We review techniques to reconstruct the EAC following ablative surgery, and introduce a rarely utilized tragal skin flap which has particular advantages for reconstruction of limited anterior EAC defects. METHODS: The terms "tragal flap", "external auditory canal", "preauricular tragal flap", "reconstructive techniques" were searched on PubMed and Google Scholar. RESULTS: Our review identified one description of a tragal flap to reconstruct the EAC following resection of a malignancy. We add an additional case of a preauricular tragal flap to reconstruct the anterior EAC following resection of a recurrent basal cell carcinoma located in the EAC that led to a circumferential defect. CONCLUSION: There are several surgical techniques that can be utilized to reconstruct the EAC. We describe a novel tragal flap used to reconstruct the anterior EAC following resection of a recurrent tumor.

Diagnosis and management of pharyngoesophageal stenosis: A comprehensive approach to prophylactic, endoscopic, and reconstructive treatment options.

BACKGROUND: Pharyngoesophageal stenosis (PES) is a serious complication that substantially impacts functional outcomes and quality of life (QOL) for up to a third of head and neck cancer patients who undergo radiotherapy. Dysphagia is often multifactorial in nature and is a devastating complication of treatment that impacts patients' QOL, general health and overall wellbeing. The authors detail the clinical presentation, risk factors, imaging characteristics, preventive measures, and multimodality treatment options for PES. METHODS: The authors present a comprehensive management algorithm for PES, including treatment by dilation, stenting, spray cryotherapy and dilation, and reconstructive treatment options utilizing different pedicled and free flaps. RESULTS: The authors advocate for a thorough assessment of the extent and degree of pharyngoesophageal involvement of PES to determine the optimal management strategy. CONCLUSIONS: The development of post treatment dysphagia requires appropriate imaging and biopsy, when indicated, to rule out the presence of persistent/recurrent cancer. Multidisciplinary management by a team of physicians well-versed in the range of diagnostic and therapeutic interventions available for PES is critical to its successful management.

Positive Lymph Node Counts in American Thyroid Association Low-Risk Papillary Thyroid Carcinoma Patients.

BACKGROUND: Current American Thyroid Association (ATA) guidelines state that patients with intermediate-risk papillary thyroid cancer (PTC) may benefit from remnant ablation. One criterion for intermediate-risk classification is >5 positive lymph nodes (LNs). We investigate whether performing step-sectioning of LNs increases the metastatic detection rate, thereby influencing ATA risk of recurrence (ROR) classification. METHODS: A retrospective review was conducted of cases in which ≥ 5 LNs were removed during thyroidectomy and ≤5 LNs were found positive for PTC. Step-sectioning was performed on the original tissue blocks. All slides were re-reviewed by a senior pathologist. RESULTS: Twenty patients met study criteria. Step-sectioning significantly increased LN yield compared to standard sectioning. In total, we found 12 new positive lymph nodes; seven (58%) were in totally new lymph nodes, while five (42%) were in lymph nodes previously read as negative. All newly discovered metastases were classified as micrometastases (≤2 mm). Of the 15 patients originally classified as low-risk, the step-sectioning protocol impacted two patients (13%), increasing ROR stratification. CONCLUSION: Intensive step-sectioning reveals additional micrometastases. More detailed analysis did not identify clinically significant nodal disease likely to impact the clinical course of patients in this study. Our study supports current standards of pathology specimen handling related to LN assessment and the impact on ATA ROR classification. Nonetheless, it is important for clinicians to understand their institution's sectioning protocol utilized to report positive and total LN counts, which could impact ATA risk stratification and denote the comprehensive nature of the LN dissection that was performed.

The use of negative pressure wound therapy in the primary setting for high-risk head and neck surgery.

BACKGROUND: In head and neck surgery, dead space is typically managed by transferring a secondary pedicled flap or harvesting a larger composite flap with a muscular component. We demonstrate the novel use of prophylactic negative pressure wound therapy (NPWT) to obliterate dead space and reduce possible communication between the upper aerodigestive tract and the contents of the neck. METHODS: We present a single-institutional case series of five patients with high-risk head and neck cancer treated with NPWT after ablative and reconstructive surgery to eliminate dead space following surgical resection. RESULTS: All patients achieved successful wound closure following NPWT, which was applied in the secondary setting to combat infection in one patient and the primary setting to prophylactically eliminate dead space in four patients. CONCLUSION: NPWT can be used to treat unfilled dead space in the primary setting of head and neck ablative and reconstructive surgery and help to avoid wound healing problems as well as the need for secondary flap transfers.

A novel radial forearm free flap design to treat pharyngoesophageal stenosis in combination with the posterior wall of the trachea.

Pharyngoesophageal stenosis (PES) is a common and serious complication of head and neck cancer treatments such as radiation therapy, chemotherapy, tracheoesophageal puncture placement, and total laryngectomy surgery. Dilation-resistant stenosis requires surgical reconstruction, often with a radial forearm free flap (RFFF). With the present technique, the authors refine their previous bipaddled free flap design used to reconstruct a persistent tracheoesophageal fistulae (TEF) in combination with PES. Accordingly, we present a novel bipaddled triangular RFFF design ideally suited to address the shape of the defect in the posterior tracheal wall that results when the TEF is opened and the esophageal and tracheal components are restored.

Osteoradionecrosis of the hyoid bone complicated by pharyngocutaneous fistula: A case report and literature review.

BACKGROUND: Osteoradionecrosis (ORN) is a well-known complication following irradiation of head and neck malignancies. ORN commonly occurs in the mandible but is rarely reported in the hyoid bone. CASE PRESENTATION: A 76-year-old female with a history of oropharyngeal squamous cell carcinoma presented with pharyngocutaneous fistula 14 years after primary chemoradiation. Imaging showed necrosis of the hyoid bone. She underwent excision of the hyoid to rule out malignancy. Pathology was negative for carcinoma, but did show extensive fragmentation and bony necrosis consistent with ORN. The patient's clinical course, surgical treatment, and management considerations are discussed here. CONCLUSIONS: Hyoid ORN should remain in the differential during diagnostic workup of previously irradiated head and neck cancer patients. The presentation of a pharyngocutaneous fistula should prompt workup to rule out malignancy before assigning a diagnosis of ORN.