Modified Radical Neck Dissection Research Articles

Heterotopic High-Grade Salivary duct Carcinoma Likely Arising within Cervical Lymph Nodes

Abstract Introduction/Objective Salivary duct carcinoma arising in heterotopic salivary gland tissue is an extremely rare occurrence, with less than five cases reported in the literature. We present a unique case of heterotopic high-grade salivary duct carcinoma likely arising within cervical lymph nodes. Methods/Case Report A 56-year-old male presented with enlarged cervical lymph nodes for few months. Physical examination was unremarkable. Computerized tomography (CT) scan of head and neck showed two enlarged level 1B lymph nodes, measuring 1.0 and 1.4 cm, with unremarkable salivary glands. Patient had left cervical level II lymph node biopsy that showed metastatic poorly differentiated carcinoma. Immunohistochemically, the tumor cells were positive for GATA3, cytokeratin 903, androgen receptor, p16 (variable nonspecific), and were negative for TTF-1, p40, p63, ER, PR and NKX3.1, favoring salivary gland ductal carcinoma. Positron emission tomography (PET) CT scan showed a hypermetabolic left submandibular gland and level 2A lymph nodes. Subsequently, the patient underwent left modified radical neck dissection. Sectioning of the submandibular gland revealed no discrete lesions. Multiple, firm to rubbery lymph nodes ranging from 0.4 cm to 2.3 cm, with tan-pink cut surfaces were identified. Microscopic examination showed normal submandibular salivary gland parenchyma. However, eight out of nineteen lymph nodes were positive for metastatic high-grade salivary duct carcinoma comprising tumor cells forming nests and cords with ample eosinophilic cytoplasm, pleomorphic round to oval nuclei and numerous mitotic figures. Several benign and malignant lymph nodes in levels I, II and IV showed heterotopic salivary gland tissue. Immunohistochemical stains for androgen receptor and p40 were positive and negative respectively, supported the final diagnosis of high-grade salivary duct carcinoma. Results (if a Case Study enter NA) NA Conclusion Given the absence of carcinoma in the completely sampled submandibular gland, the origin of the intra- nodal tumor deposits was most likely to be heterotopic salivary gland tissue. This case emphasizes the importance of meticulous pathological sampling required for definitive diagnosis.

6504 Cerebellar Metastases from Papillary Thyroid Cancer; An Unusual Presentation

Abstract Disclosure: L.E. Chozet: None. A. Gilbert: None. M.A. Escobar Vasco: None. Background: Differentiated papillary thyroid cancer is known to have a very favorable prognosis. Brain metastases arising from papillary thyroid carcinoma are a very rare complication seen in approximately 1% of all cases of differentiated thyroid cancer with cerebellar metastases being even more uncommon. We present a case of a patient presenting with ataxia as the initial and only symptom of papillary thyroid carcinoma, found to have cerebellar metastases. Clinical Case: A 68-year-old man presented with ataxia for 1 week prior to arrival to hospital. CT head revealed hyperdense lesions in the right frontal lobe and left posterior cerebellar hemisphere. The patient underwent resection of left cerebellar mass with final pathology consistent with metastatic papillary thyroid carcinoma. Tumor cells were positive for TTF-1, thyroglobulin, CAM5.2, CK7, and PAX8, and negative for CK5/6, CK20, inhibin, and Napsin A. Ultrasound of the thyroid revealed multinodular goiter with dominant left thyroid lobe nodule 4 cm in size. PET CT showed left Thyroid mass with direct extension to adjacent lymph nodes, right anterior rib mass, left adrenal metastasis and right frontal lobe and left cerebellar metastasis. He received stereotactic radiosurgery with 5 out of 5 treatments completed. He subsequently underwent total thyroidectomy with left modified radical neck dissection, with pathology showing pT3bN1bM1. Next Generation Sequence positive for V600E, RADS1CR193, TERT PROMOTER -124C>T. After multidisciplinary team discussion, it was determined that the best course of action was to refer the patient to MD Anderson for evaluation, candidacy for prospective therapeutic clinical trials. Conclusion: This case demonstrates how differentiated papillary thyroid cancer, despite its favorable prognosis, can still prove to be a dangerous disease especially if undiagnosed for several years. This case also illustrates how papillary thyroid carcinoma can remain clinically silent for years and first present with atypical symptoms consistent with advanced metastases. Presentation: 6/2/2024

6847 Poorly Differentiated Thyroid Cancer: A Rare Entity

Abstract Disclosure: S. Fatima: None. S. Ward: None. A. Champion: None. Introduction: Poorly differentiated thyroid carcinoma (PDTC) is a rare thyroid carcinoma originating from follicular epithelial cells. Regarding the degree of differentiation, PDTC ranks between differentiated thyroid cancer and anaplastic thyroid cancer. We hereby present a rare case of PDTC. Case: 29-year-old female with a history of metastatic papillary thyroid cancer (PTC) presented to the emergency department with shortness of breath. She initially noticed a left thyroid mass in 2021. CT neck in 1/2022 showed a 7 cm left thyroid mass with substernal extension, small right thyroid mass with tracheal compression, left bulky cystic nodal masses extending anterior and posterior to carotid and internal jugular vein. PET scan in 3/2022 showed left 7.6 cm thyroid mass SUV 12.1 with tracheal compression, left level II-IV adenopathy with level IV nodal masses 5.1 cm SUV 4.5. Ultrasound-guided FNA in 4/2022 showed PTC in left 8.7cm thyroid nodule; right 2.8 cm nodule showed Atypia of Undetermined Significance; Left 5.5 cm neck level III lymph node (LN) showed PTC metastasis; right 5.1 cm neck level III LN showed PTC metastasis (+ thyroglobulin and TTF-1). CT chest in 11/2022 showed additional involvement of manubrium. Repeat core needle biopsy of left thyroid mass showed left invasive thyroid carcinoma. She was started on neoadjuvant Lenvatinib in 1/2023. Follow-up CT neck in 5/2023 showed a reduction in the size of the left thyroid mass to 5.5cm x 5.8cm x 6.5cm. At this time, she had symptoms of dysphagia, orthopnea, weight loss of about 60 lbs and neck pain. In 11/2023 at time of current presentation she underwent total thyroidectomy, bilateral modified radical neck dissection and manubriectomy. Surgical pathology showed PDTC in left thyroid mass, PTC in right thyroid mass with metastatic PDTC in left proximal sternocleidomastoid, manubrium and LN involvement in neck and mediastinum. OmniSeq Insight testing showed APC and BRCA1 gene mutations, negative BRAF V600E, RET fusion, RET mutation, NTRK1/2/3 fusion and PD L1 immunohistochemistry score is <1%. The patient is planned to receive [1]3[1]I ablation therapy. Conclusion: PDTC accounts for 3–5% of all thyroid carcinomas. The 5, 10-, and 15-year survival rates of patients are 50–85%, 34–50%, and 0%, respectively. RAS gene alterations are found in 25–35%, BRAF mutation in 15–27%, TERT promoter mutation in 40% and mutant TP53 in 16–28% of PDTCs. TERT promoter gene and TP53 mutation usually indicate an aggressive phenotype and a dismal prognosis. Surgery, [1]3[1]I therapy, and external beam radiotherapy constitute the mainstay of traditional treatment for patients with advanced disease; however, treatment is challenging. Tyrosine kinase inhibitors i.e, sorafenib and lenvatinib, have been used in cases of progressive, recurrent, or metastatic disease not responsive to [1]3[1]I therapy. Immunotherapy may be an option in PD-L1-positive tumors. Presentation: 6/1/2024

8465 Diagnostic Conundrum: The Mystery of Metastatic Papillary Thyroid Cancer with Persistently Elusive Thyroglobulin

Abstract Disclosure: P. Vemparala: None. M. Bollineni: None. Introduction- Among endocrine malignancies, differentiated thyroid cancers account for the majority with most of them boasting a favorable prognosis. Thyroglobulin, a pivotal biochemical marker, aids in detecting recurrence or persistent disease when combined with neck ultrasound, I-131 scintigraphy, and FDG PET scans. Anti-thyroglobulin antibodies, found in a quarter of cases, can falsely lower serum thyroglobulin levels in immunometric assays. Our intriguing case features a patient with metastatic papillary thyroid cancer, yet thyroglobulin levels persistently eluded detection. CASE PRESENTATION- A 33-year-old female presented initially to an outside facility with neck swelling, leading to a diagnosis of a 4 x 3 cm papillary thyroid cancer (PTC) in the right lobe and a 0.5 x 0.5 cm focus of PTC in the left lobe, accompanied by capsular extension, malignant cells in the left lobe margin, and lymphovascular invasion. After total thyroidectomy and lymph node exploration, radioactive iodine scan detected disease in right-sided lymph nodes, treated subsequently with radioactive iodine ablation. Two years later, she presented to our clinic with neck swelling, voice changes, and fatigue. Thyroglobulin level was measured which returned at <0.1 ng/ml, however thyroglobulin antibodies were elevated at 292 IU/ml, albeit decreased from a value of 431.5 IU/ml at initial diagnosis. Elevated thyroglobulin antibodies complicated interpretation, prompting liquid chromatography-mass spectrometry (LC-MS) for accurate measurement of thyroglobulin, which returned at <0.5 ng/ml. Ultrasound indicated metastatic disease in right cervical lymph nodes, confirmed by fine needle aspiration. In-office ultrasound-guided FNA of additional nodes validated metastasis. Modified radical neck dissection revealed metastatic PTC in 7 out of 34 lymph nodes. Surprisingly, thyroglobulin levels remained <0.5 ng/ml, pre- and post-operatively. Referred for radioactive iodine ablation, her complex journey underscored the challenges in monitoring thyroid cancer recurrence or persistent disease with thyroglobulin levels even by methods such as mass spectrometry. Conclusion- Key learnings from this case highlight the importance of cognizance in utilizing thyroglobulin levels to guide adjuvant therapy decisions and for postoperative monitoring in high risk patients, as low levels do not rule out recurrence or persistence. Anti-thyroglobulin antibodies pose challenges, necessitating techniques like LC-MS. Finally, recognizing “nonsecretor” thyroid cancers, an aggressive subgroup with poorer prognosis, is vital as they often present with low or undetectable thyroglobulin levels. Presentation: 6/2/2024

Association between cervical lymph node dissection and dementia: a retrospective analysis

BackgroundDementia, characterized by memory loss and cognitive impairment, considerably impacts individuals and society. Our research focused on cervical lymph nodes, crucial for CNS lymphatic drainage, in the context of dementia. We hypothesized that the patients with head and neck cancer (HNC) undergoing cervical lymph node dissection (CLND) may have increased dementia risk due to obstructed lymphatic pathways. MethodsWe conducted a retrospective analysis of the electronic medical records from patients over 60 years diagnosed with HNC who underwent CLND between March 2007 and April 2023. We collected demographic data, calculated dementia incidence rates, and compared parameters between patients with and without dementia. ResultsAmong the 251 patients with HNC who underwent CLND, 234 were men and 17 were women. Nine male patients developed dementia within an average of 50.1 ± 35.3 months post-surgery. The dementia incidence rate was 0.7 per 100 patient-years, with a cumulative incidence of 10.34% over 8.6 years. The CLND patterns were associated with dementia (p = 0.028), with bilateral supraomohyoid neck dissection (SOHND)/modified radical neck dissection (MRND) and unilateral MRND combined with any neck dissection type on the other side presenting higher risks than unilateral MRND/SOHND (p = 0.016). ConclusionPatients with HNC undergoing bilateral and comprehensive lymph node dissection showed higher dementia risk, highlighting the importance of the neck’s lymphatic role in brain health. These findings may guide future surgical practices.

Incidental Finding of Double Posterior Belly of Digastric Muscle in Head and Neck Cancer Patient.

The digastric muscles have important roles in swallowing, chewing, speech, and landmark identification during neck dissection. The posterior belly of the digastric muscle (PBDM) is often useful for defining boundaries in surgical neck dissection as it contributes to the carotid, submandibular, and submental triangles. The cadaveric prevalence rate of anatomic variations in the digastrics has been reported to be 31.4% of the population with most occurring in relation to the anterior belly of the digastric muscle (ABDM). Few reports describe variations in the PBDM. While anatomic variants of the digastric muscles do not present with clinical manifestations, they can be mistaken as neck masses and contribute to intraoperative complications. We present a case report of a 73-year-old male with a past medical history significant for Parkinson's Disease, who was incidentally found to have a duplicate PBDM intraoperatively while receiving surgical management of a left buccal squamous cell cancer. Nine months prior to surgery, the patient began experiencing trismus and some mild dysphagia that were eventually worked up to reveal left buccal squamous cell carcinoma (SCC). Prior to this, the patient did not have clinical symptoms demonstrating dysfunction that could be related to or indicative of this anatomical abnormality preceding symptoms related to left buccal SCC growth. The procedure included a wide local excision, left modified radical neck dissection and left submental artery island flap with suprahyoid neck dissection. The superior duplicate PBDM was found to be overlying the stylohyoid muscle. It is important for surgeons operating in the head and neck to be aware of the possibility of this rare variation, and to be conscientious when it is identified so that it does not prohibit or limit a thorough dissection of the neck structures where oncologic clearance is paramount.

Clinical outcomes of bilobed platysma myocutaneous flap technique with neck dissection in lower lip squamous cell carcinoma

BackgroundSquamous cell carcinoma (SCC) in the lower lip is among the most frequently encountered types of cancer. As the size of this cancer increases, the need for reconstruction becomes evident, posing a significant challenge. Depending on the staging results in these patients, neck dissection may be recommended. ObjectiveThis study aims to demonstrate the successful application or feasibility of our Bilobed Platysma Myocutaneous Flap technique in patients with lower lip SCC. MethodsThe Bilobed Platysma Myocutaneous Flap was applied to all patients. Following TNM staging, supraomohyoid and/or radical neck dissection were performed. Surveys were conducted with the patients, and scoring was implemented based on the results for evaluation. ResultsBetween 2014 and 2018, 23 patients underwent treatment with this flap, and all flaps survived. Among these patients, bilateral supraomohyoid neck dissection was performed on 14, while modified radical neck dissection on one side and supraomohyoid neck dissection on the other side were conducted on the remaining 9 patients. Throughout the 5-year follow-up period, no recurrence was observed in the patients. ConclusionThe combination of the Bilobed Platysma Myocutaneous Flap technique and neck dissection can be successfully employed in the reconstruction and treatment of lower lip cancers.

Comparison of actual prognosis between unilateral and bilateral central neck dissection in modified radical neck dissection patients with no clinical central lymph node metastasis: a retrospective cohort study.

This study aimed to evaluate the long-term prognosis of contralateral central neck dissection (CND) in papillary thyroid cancer (PTC) patients with ipsilateral lateral neck metastasis. We compared the actual recurrence rate according to the extent of CND-ipsilateral and contralateral sides. A total of 708 PTC patients who underwent total thyroidectomy and concomitant ipsilateral or bilateral CND with ipsilateral lateral neck dissection between January 1997 and December 2022 at Samsung Medical Center were retrospectively analyzed. The median follow-up time was 118 months. Locoregional recurrence was observed in 26 patients (7.9%) and 30 patients (7.9%) in the ipsilateral and bilateral CND groups, respectively. There were 6 contralateral recurrence cases (1.8%) in the ipsilateral CND group and 6 cases (1.6%) in the bilateral CND group. There was only 1 contralateral central neck recurrence in the ipsilateral CND group. The incidence of hypocalcemia (P = 0.007) was higher in the bilateral CND group compared to the ipsilateral CND group. Surgeons may consider performing only unilateral CND-the side where tumor is for therapeutic purposes to reduce surgical complications.

Robotic versus open surgery for thyroidectomy and modified radical neck dissection in patients with papillary thyroid carcinoma with clinical lateral neck node metastasis (cN1b): Effectiveness and safety, oncological outcomes and long-term quality of life.

e18069 Background: Open thyroidectomy (TT) with modified radical neck dissection (MRND) is used for papillary thyroid carcinoma (PTC) with clinical lateral neck node metastasis (cN1b). robotic surgery for TT with MRND is being carried out and some studies have confirmed its efficacy. However, such studies are limited by indicators and samples. The study aimed to compare robotic TT with MRND with open surgery in patients with cN1b PTC in efficacy, safety, oncological outcomes and quality of life. Methods: In this retrospective cohort study, 2027 patients receiving MRND between January 2016 and December 2021 were enrolled. After exclusion, 1153 PTC patients met the inclusion criteria, in which 168 (14.57%) underwent robotic surgery and 985 (85.43%) underwent open surgery. Propensity score matching (PSM) at a 1:2 ratio was performed to minimize bias. We compared the efficacy, safety and oncological outcomes before and after PSM, we also evaluated the quality of life of patients after PSM. Results: Before and after PSM, the number of central lymph nodes ( p<0.001) and lateral cervical lymph nodes(p<0.001),and the number of positive lateral cervical lymph nodes(before PSM p=0.037, after PSM, p=0.018 ) in the robotic group were lower than those open group. RAI-avid lesion in postoperative 131 RAI scan showed no difference between two groups and showed similar complication rates before or after PSM, including chyle leakage, infection, and permanent hypoparathyroidism. Because the rate of parathyroid misresection and the number of transplanted parathyroid glands were improved, robotic was superior to open group in preventing transient hypoparathyroidism. The patients were followed up for mean 50.57 months in the robotic group and 51.78 months in the open group. There was no difference between two groups in recurrence rate (before PSM: 5/168 [2.98%] vs 32/985 [3.25%], p>0.99; after PSM: 5/168 [2.98%] vs 15/336 [4.46%], p=0.572) and distant metastasis rate (before PSM: 1/168 [0.60%] vs 3/985 [0.30%], p>0.99; after PSM: 1/168 [0.60%] vs 1/336 [0.30%], p>0.99). We conducted a quality of life survey in 504 patients after PSM and collected 317 copies, of which 316 were valid. Compared with the open group, the robotic group had similar performance in health-related quality of life(HR-QOL) and the QOL issues specific to thyroid cancer, including subjective voice, dysphagia, neck and shoulder disability. The scores of scar showed a significant difference in the appearance and psychosocial impact of scars between two groups (p<0.001). Conclusions: Robotic surgery can provide more meticulous operation to reduce postoperative complications and better quality of life, especially scars, there is no significant difference in oncologic outcomes between two groups.

Squamous Cell Carcinoma of Nasofacial Groove

Abstract Introduction: Cutaneous squamous cell carcinoma is a malignant tumour that develops in the squamous cells that make up the middle and outer layers of the skin. It often forms on parts of skin frequently exposed to sunlight. It is usually not life-threatening, though it can be aggressive causing serious complications. However, nasofacial groove is a very uncommon area for the origin of squamous cell carcinoma. Case Report: A 65-year-old housewife with hypertension and type 2 Diabetes Mellitus presented with painless swelling over right nasofacial groove for last 5 months which was insidious in onset, gradually progressive to reach the present size. On clinical examination, oval, localized, non-tender, hard 2cm x 2cm swelling was found over right nasofacial groove. Diagnostic nasal endoscopy was within normal limit. Computed Tomography showed a well-defined heterogenous oval mass over the right maxilla extending over right nasofacial region. Aspiration cytology yielded a few round to oval epithelial cells and fibrous stroma in a haemorrhagic background. A provisional diagnosis of appendageal tumour of nasofacial groove was made. Surgical excision was done under general anaesthesia. Gross examination showed predominantly solid and grey mass. Microscopically the lesion showed features of moderately differentiated squamous cell carcinoma. Further Total Maxillectomy with Modified Radical Neck Dissection type 3 has been done. Discussion: Squamous cell carcinoma of the skin may mimic nasolabial cyst. Hence the diagnosis should be kept in mind while dealing with a suspicious case of nasolabial cyst.

Neurofibroma of the vagus nerve as an incidental finding during left modified radical neck dissection for papillary thyroid cancer

Neurofibroma of the vagus nerve as an incidental finding during left modified radical neck dissection for papillary thyroid cancer

Never too young for a salivary gland carcinoma ex-pleomorphic adenoma

BackgroundCarcinoma ex-pleomorphic adenoma (CXPA) can either arise primarily as a de novo or from the malignant transformation of a benign pleomorphic adenoma (PA). CXPA mostly occurs in adults aged 50 to 70 years; hence, the occurrence of CXPA in younger ages is not common.Case presentationWe report a 27-year-old female who had a history of submandibulectomy for pleomorphic adenoma, and presented with recurrent left submandibular swelling for 4 months. The mass was rapidly increasing in size and was associated with occasional throbbing pain. Examination showed a multilobulated, firm left submandibular swelling with no overlying skin changes. FNAC was performed twice, by conventional and ultrasound-guided techniques, and both concluded as benign salivary gland tumours. CT scan and MRI revealed a well-demarcated tumour with an area of necrosis within, with no obvious invasion into surrounding soft tissue and no significant lymphadenopathy. Having high suspicion of a malignant transformation, the tumour was resected with a concurrent modified radical neck dissection. The histopathological examination confirmed a carcinoma ex-pleomorphic adenoma with the myoepithelial malignant component. The patient subsequently received adjuvant radiotherapy. This case demonstrated that CXPA, although rare, can occur in young adults. Pre-operative FNAC and radiological imaging may mimic a pleomorphic adenoma.ConclusionThe presence of recurrent tumours with rapid growth should alarm the clinician about a possible malignant transformation of a benign parotid tumour.

Safety and surgical outcomes of single-port trans-axillary robot-assisted thyroidectomy: Experience from a consecutive series of 300 patients.

Since the introduction of the single-port (SP) robotic system, SP trans-axillary robot-assisted thyroidectomy (SP-TART) has been performed. We aimed to evaluate the safety and surgical outcomes of SP-TART in a consecutive series of 300 cases. We analyzed 300 patients with thyroid disease who underwent SP-TART from October 2021 to May 2023 in St. Mary's Hospital in Seoul, Korea. We analyzed the patients' clinicopathological characteristics and perioperative outcomes according to surgical extent. Of the 300 cases analyzed, 250 patients underwent less than total thyroidectomy (LTT), 31 patients underwent total thyroidectomy (TT), and 19 patients underwent TT with modified radical neck dissection (TT c mRND). The mean operative times for LTT, TT, and for TT c mRND were 69.8±23.6, 104.2±30.7, and 223.7±72.4min, respectively. Complications, including postoperative bleeding, transient hypoparathyroidism, and vocal cord palsy, were observed in nine, six, and six LTT, TT, and TT c mRND cases. The SP-TART method is a safe and feasible surgical option with a short operative time, good surgical outcome, and excellent cosmetic results.

Effect of proprioceptive neuromuscular facilitation versus low level laser therapy on shoulder adhesive capsulitis post-neck dissection surgery

IntroductionNeck dissection (ND) operations are performed to treat known metastatic neck illness. These operations have been associated with chronic neck and shoulder problems. In patients who have had a ND, adhesive capsulitis (AC) is one of the causes of shoulder dysfunction.MethodsForty patients with AC following modified radical neck dissection (MRND) surgeries were chosen at random and divided into two groups of equal size. The low-level laser therapy (LLLT) group (group A) received LLLT with: wavelength – 830 nm, output – 50 mw, maximum frequency – 5000 Hz, pulse duration – 50 ns, and average dose – 9 J/cm2 for 20 min, plus traditional physical therapy (mobilisation technique, myofascial release, range of motion (ROM), and strengthening exercises) for 30 min. The proprioceptive neuromuscular facilitation (PNF) group (group B) received PNF for 25–30 min in addition to traditional physical therapy. The treatment period was 3 times each week and lasted for eight weeks. The discomfort in the shoulder was measured using the visual analogue scale (VAS). Shoulder impairment and pain were assessed by the SPADI scale and the shoulder ranges of motion were assessed using the universal goniometer technique. All measures were taken before and after the intervention.ResultsThe findings reveal that there was a significant enhancement in all variables in both groups A and B after therapy compared to before the treatment (p < 0.001). After therapy, there were no obvious changes in the VAS and SPADI values among the groups (p > 0.05). However, statistical analysis showed significant improvement in the PNF group (group B) in shoulder flexion, abduction and external rotation in comparison to that of the LLLT group (group A) after treatment (p < 0.001).ConclusionsPNF proved to be more effective than LLLT in increasing ROM but was as effective as LLLT in decreasing shoulder pain and dysfunction in AC post ND surgery.

Variations of the trapezius branch of the accessory nerve: an anatomic study

Although modified radical neck dissections have increased in popularity to reduce morbidity secondary to intraoperative accessory nerve damage, inadvertent injury still often occurs. As this phenomenon is thought to be due to anatomic variation in the trapezius branch of the accessory nerve, it is imperative to better understand the nuances of these anatomic variations to better inform surgical decision-making. A total of 24 accessory nerves were dissected, exposed, and traced in 15 cadavers. Three aspects of the accessory nerve were identified and recorded: the course of the trapezius branch in relation to the sternocleidomastoid, the number of trapezius branches at muscle insertion, and the number of cervical rootlet contributions. Four different anatomic patterns for the trapezius branch were identified, with the most common being where the trapezius branch separates from the main accessory nerve just medial to the sternocleidomastoid and courses deep to the sternocleidomastoid (58.3%). Most (75%) trapezius branches entered the muscle as a single nerve, whereas some (21%) were inserted as two separate nerves. The number of cervical rootlet contributions for each trapezius branch varied from zero to three. Bilateral anatomic variations were also noted. Even when the accessory nerve and its branches are thought to be spared during neck dissection, patients may postoperatively present with different degrees of accessory nerve damage. There may be unrecognized anatomic pathways that the nerve takes that may confer a higher risk of unintentional damage, especially those that have greater exposure within the anterior triangle unprotected by the sternocleidomastoid.

The Effect of Laterality in Modified Radical Neck Dissection on the Risk of Intraoperative Bradycardia: A Retrospective Cohort Study.

Background Intraoperative bradycardia is a hardly studied complication of modified radical neck dissection (MRND). Methods Using convenient sampling, we retrospectively studied a cohort (n = 159) of patients who underwent MRND at Papanikolaou General Hospital, Thessaloniki, Greece between 2019 and 2020 to investigate whether MRND laterality (bilateral vs. unilateral) affects the occurrence of intraoperative bradycardia (a pulse rate lower than 50 bpm). Results Roughly two-thirds of the patients underwent unilateral MRND, and the rest underwent bilateral MRND. Bradycardia was observed in 25.8% of the cohort. We used logistic regression and investigated several potential confounding factors. Unilateral MRND was associated with a lower risk of intraoperative bradycardia compared to bilateral MRND in the simple regression model (relative risk (RR): 0.555, 95% confidence interval (CI): 0.331-0.932, p = 0.027). MRND laterality was not significantly associated with intraoperative bradycardia (p = 0.082) in the multiple regression model, whereas an American Society of Anesthesiologists physical status (ASA-PS) score of 3 vs. 4 (adjusted odds ratio (aOR) = 0.125, 95% CI: 0.0340-0.457, p = 0.002), the presence of atrial fibrillation (aOR = 11.4, 95% CI: 4.10-31.8, p < 0.001) and induction of anesthesia with dexmedetomidine (aOR = 4.57, 95% CI: 1.34-15.6, p = 0.015) were significantly associated with intraoperative bradycardia. Conclusions MRND laterality was close to statistical significance. Bigger sample sizes may provide more definitive information since the effect of MRND laterality on intraoperative bradycardia remains unclear. Our findings can inform clinical practice so that clinicians know when to expect bradycardia and are better prepared to manage it.

Bilateral axillo-breast approach (BABA) robotic neck dissection for papillary thyroid carcinomas

Papillary thyroid carcinoma (PTC), the most commonly diagnosed thyroid malignancy, frequently presents with lymph node metastases. Effective management of metastatic lymph nodes is crucial due to the disease's high recurrence rates. Herein, we present our approach to robotic thyroidectomy and central/lateral neck node dissection, which has shown comparable oncologic outcomes, reduced complications, and improved cosmetic results compared to open surgeries. We detail the surgical procedure, from patient positioning and flap dissection, through central and lateral neck dissection, to closure. The BABA robotic modified radical neck dissection (MRND) is primarily recommended for patients with well-differentiated thyroid carcinoma, predominantly PTC, presenting with suspected or pathologically confirmed lateral neck metastasis. We also discuss the application of the da Vinci robot settings in performing precise procedures and preserving critical anatomical structures. This comprehensive review provides insights into the effectiveness of BABA robotic thyroid surgery and central/lateral neck node dissection in managing PTC.

Extraskeletal Myxoid Chondrosarcoma of Floor of Mouth-A Rare Case Report and Review of Literature.

Chondrosarcomas are rare malignancies of the cartilage and myxoid chondrosarcoma is its variant which commonly occurs in soft tissue of extremities. Extraskeletal chondrosarcoma is a rare malignant neoplasm of bone or soft tissue origin and is characterized by the presence of spindle cells admixed with well differentiated cartilage or chondroid stroma. They are mostly radioresistant tumours and surgical resections with adequate margins is considered as the ideal treatment modality with adjuvant radiotherapy in high grade tumours and add on chemotherapy, in case of presence of poor prognostic factors. A 51-year-old diabetic, hypertensive female patient presented to our outpatient department with difficulty in chewing food for a duration of 6 months. On clinical examination, she had an ulceroproliferative growth involving right lower alveolus and floor of mouth. MRI face and neck with contrast showed a 4.1 × 2.9 × 4.5cm lesion involving right lower alveolus extending to floor of mouth. Biopsy showed features of extraskeletal myxoid chondrosarcoma. She was planned for upfront surgery (Right composite resection with modified radical neck dissection with free fibula flap). Patient was stable post-surgery and was discharged in stable condition. Final histopathology report was high grade myxoid chondrosarcoma. The case was presented in tumour board and the patient was planned for adjuvant radiotherapy. She has been on regular follow up for the past 2 years and shows no signs of recurrence. Extraskeletal myxoid chondrosarcoma of oral cavity is a rare entity and very few cases are reported. It is a malignant neoplasm which is diagnosed with the help of immunohistochemistry. Surgery is the ideal modality of treatment accompanied by adjuvant radiotherapy in cases of high-grade tumours.

SAT535 ANKRD26-RET Fusion Positive Metastatic Papillary Thyroid Carcinoma - Advanced Presentation of a Rare Mutation

Abstract Disclosure: H. Hashmi: None. A. Ankireddypalli: None. L. Burmeister: None. A. Nelson: None. K. Amin: None. Background: While rearranged during transfection (RET) protooncogene mutations have been commonly associated with thyroid malignancy, ankyrin repeat domain containing protein 26 (ANKRD26) has been primarily linked to hematologic malignancy. Exon 29 of ANKRD26 (Chromosome [Chr] 10p12.1) has been shown to fuse with exon 12 of RET (Chr 10q11.21), resulting in a genetic fusion mutation ANKRD26:RET. This is a rare genetic mutation in papillary thyroid cancer with only one previously reported case. We report the first case in the US of this novel genetic mutation with a unique clinical presentation. Clinical Presentation: A 48-year-old, male patient presented with lower back pain radiating to the lower extremities of one year duration. MRI lumbar spine revealed an irregular mass lesion in the L1 vertebral body with extraosseous soft tissue extension, L1 compression fracture and extension into the T12 body. CT CAP revealed a 4.8 x 3.6 cm, heterogenous right thyroid lobe with tracheal compression and sub centimeter pulmonary nodules in the left lower and right middle lobes. Biopsy of the L1 paravertebral mass was diagnostic for metastatic thyroid carcinoma of a follicular pattern. Molecular testing with a next generation sequencing fusion profile assay was positive for ANKRD26:RET gene rearrangement. Thyroid ultrasound was notable for a solid, hypoechoic, 3.2 x 3.1 x 2.9 cm right lobe nodule with echogenic foci and level 4 lymph nodes with loss of reniform shape and fatty hilum. FNA of the nodule and right level 4 lymph node was suspicious for follicular neoplasm. The patient was admitted for acute cord compression necessitating extensive laminectomy, vertebral reconstruction and resection of the L1 paraspinal tumor. Pathology was positive for metastatic, follicular variant, papillary thyroid carcinoma. Total thyroidectomy, central and right modified radical neck dissection was performed. Pathology demonstrated a 4.2 cm papillary carcinoma, follicular type with tall cell variant; confined to the thyroid. Extensive angioinvasion (≥ 4 vessels) and lymphatic invasion was present. 10/32 positive lymph nodes. TNM grading was T3aN1bM1. Summary: The only other case of ANKRD26-RET fusion positive papillary thyroid cancer in the literature was reported by Staubitz et al in Germany in 2019. They reported a case of a 78-year-old male with follicular variant papillary thyroid carcinoma (pT3,pN0,M0). To our knowledge, our case is the second worldwide and the first to be reported in the United States of this rare fusion protein positive thyroid cancer. Such an aggressive presentation with distant osseous metastases has to our knowledge not been previously described. Conclusion: The clinical and therapeutic implications of this rare genetic mutation are not currently well elucidated. We present this case with the intent to expand the existing literature and increase recognition of this rare genetic mutation. Presentation Date: Saturday, June 17, 2023

Cranio-Caudal Identification and Preservation of Spinal Accessory Nerve during Modified Radical Neck Dissection

Introduction: The spinal accessory nerve (SAN) is encountered during neck dissection surgeries and is at the highest risk for iatrogenic injury, which may lead to shoulder syndrome. This functional deformity can be avoided by preservation of SAN in modified radical neck dissection (MRND). Description: Many techniques are described in the literature for SAN preservation, one of which is the identification of Erb’s point and dissection in the posterior triangle where the SAN leaves the sternocleidomastoid (SCM) muscle. However, this technique for identification and preservation of SAN requires a skilled and trained surgeon to avoid any iatrogenic injury to SAN. Conclusion: Therefore, a study was carried out on 30 patients to find if the cranio-caudal dissection of SAN helps in the preservation of the nerve during MRND surgeries at the beginner’s level.