Diagnostic challenges and perioperative management of a lateral cystic neck mass in an adult patient with hemophilia B: A case report

Abstract

Lymphatic malformations and branchial cleft anomalies are rare congenital lesions that can present similarly as cystic neck masses, often in childhood, but occasionally in adults. Differentiating between the two can be challenging, especially when clinical, radiographic, and cytologic findings overlap. We present the case of a 41-year-old male with hemophilia B and a right lateral cystic neck mass, underscoring preoperative diagnostic ambiguity and illustrating perioperative coordination required for safe surgical excision in a patient with a bleeding disorder. On examination, patient’s neck had a mobile, cystic feeling, 5 cm right upper neck mass lateral or involving the sternocleidomastoid muscle. Computed tomography imaging revealed a 5 cm cystic lesion deep to the sternocleidomastoid muscle. Ultrasound-guided fine needle aspiration showed bland lymphocytes, suggesting either a second branchial cleft cyst or macrocystic lymphatic malformation. Due to diagnostic uncertainty and the potential for future infection, the patient underwent surgical excision following perioperative Factor IX replacement. Final pathology confirmed a lymphatic malformation. This case highlights the diagnostic overlap of lateral cystic neck masses in adults and emphasizes the importance of multidisciplinary care in patients with comorbidities such as hemophilia.

Introduction

Lymphatic malformations and branchial cleft anomalies are congenital neck masses. These lesions are uncommon and typically present in infancy or childhood. However, they may go undetected until adulthood, often revealing themselves through superimposed infection or as incidental findings on imaging. ¹ These anomalies can significantly impact quality of life, both psychologically and physically, depending on the severity and location of the defect. ² These lateral cystic neck masses can pose diagnostic challenges because their clinical and radiographic features often overlap, particularly when evaluated in adulthood rather than childhood.

The differential diagnosis for a lateral cystic neck mass in an adult is broad. Lesions include branchial cleft anomalies, lymphatic malformations, venolymphatic malformations, cystic salivary gland tumors, infectious lymphadenitis with necrosis, thymic cysts, and laryngoceles.^3,4 Additionally, metastatic lymph nodes may undergo cystic degeneration presenting as a cystic neck mass. ⁵

This case highlights the diagnostic ambiguity between lymphatic malformations and branchial cleft anomalies in an adult patient and underscores additional perioperative considerations in the setting of hemophilia B.

Case description

A 41-year-old male patient presented to our head and neck surgical oncology clinic for evaluation of a right lateral neck mass that had been present for several years. The mass had intermittently fluctuated in size in association with upper respiratory infections. Upon examination, the mass was mobile, cystic feeling, 5 cm, on the upper right neck. In-office oral cavity and oropharyngeal examination demonstrated no tonsillar asymmetry, mucosal lesions, or palpable base-of-tongue abnormalities. A computed tomography (CT) scan demonstrated a cystic lesion deep to the right sternocleidomastoid muscle that was 5 cm in greatest dimension (Figure 1). There were no associated inflammatory changes or other lesions within the neck or aerodigestive tract. The patient did not undergo a neck ultrasound or magnetic resonance imaging (MRI). CT imaging and fine needle aspiration (FNA) findings were considered sufficient to guide surgical management in the absence of concerning signs for malignancy. Direct laryngoscopy performed at the time of surgery revealed no upper airway abnormalities. FNA of the mass performed at an outside hospital demonstrated bland lymphocytes, consistent with reactive lymphoid tissue and without malignant cells. Thyroglobulin washout was not obtained, and cytology did not raise suspicion for metastatic thyroid carcinoma. These findings supported a benign etiology.

Figure 1.

Axial imaging demonstrating a 5 cm cystic mass located deep to the right SCM muscle, without signs of surrounding inflammation.

Surgical excision was recommended to obtain a definitive diagnosis and to prevent future episodes of superimposed infection. Informed consent included potential injury to the spinal accessory nerve and possible division of the sternocleidomastoid muscle to facilitate access to remove the mass. The hematology team provided recommendations for management of the patient’s hemophilia B perioperatively. On the morning of his surgery, he received an infusion of factor IX. Intraoperatively, the mass involved levels 2 and 3 of the neck. It was bordered by the sternocleidomastoid muscle, the carotid sheath, the prevertebral fascia, and floor of neck musculature. The spinal accessory nerve was identified, and the mass was easily dissected free of the nerve, sternocleidomastoid, and carotid sheath structures. The mass was somewhat adherent and difficult to separate from the prevertebral fascia and floor of neck muscles. Once the mass was freed circumferentially, it was removed intact and sent for permanent pathology (Figures 2 and 3). There was minimal blood loss throughout the procedure despite the patient’s hemophilia. The patient was admitted for overnight observation with a drain and was discharged the next day. He did not experience any bleeding complications postoperatively. Final pathology demonstrated a 5.6 cm lymphatic malformation. The patients were doing well at his postoperative clinic follow-up and happy with the outcome.

Figure 2.

Gross specimen of the excised mass measuring approximately 5.6 cm in greatest dimension, consistent with a lymphatic malformation.

Figure 3.

This lymphatic malformation, or lymphangioma, is a benign proliferation of lymphatic vessels. Side A (2×) demonstrates dilated lymphatic channels lined by a thin, flat endothelium. Side B (20×) highlights the endothelium lining the cystic spaces with lymphocytic aggregates within the stroma.

Discussion

The pathology report confirmed a lymphatic malformation. While lymphatic malformations are uncommon in adults, they should be considered in the differential for cystic neck masses, particularly when imaging or cytology suggests lymphatic origin. While these are more commonly found in children at an incidence between 1 in 6000 and 16000 patients, it is even less common for it to arise in adulthood. ⁶ There are no previous reported cases of lymphatic malformation and hemophilia. However, it should be noted that hemophilic pseudotumor is a rare complication of recurrent hemorrhage in hemophiliacs that results in an encapsulated cystic mass. Often in the extra-articular musculoskeletal system but is more frequently found in the extremities. ⁷

Lymphatic malformations result from abnormal development of lymphatic channels and present as soft, compressible masses, often in the posterior triangle of the neck.^8,9 They often infiltrate surrounding tissue planes, which can make complete resection technically challenging and increase the risk of recurrence. ⁴ These lesions are congenital in nature but may remain quiescent for years before becoming clinically apparent, often triggered by infection, trauma, or hormonal changes. In adults, delayed presentation can complicate diagnosis as the appearance and behavior of these masses may mimic other etiologies such as branchial cleft anomalies, necrotic lymphadenopathy, or cystic metastases.^3,4 This overlap underscores the importance of correlating radiologic findings with clinical history and histologic confirmation.

Imaging plays a central role in evaluating adult lateral cystic neck masses, particularly given the importance of excluding malignancy. CT is often the initial modality because of its accessibility and ability to define lesion extent. MRI may further characterize fluid components or delineate involvement of deep tissue planes, and ultrasound can help assess superficial cystic masses. In this case, CT imaging demonstrated a well-circumscribed cystic lesion without concerning features for malignancy, and FNA showing reactive lymphoid tissue supported a benign etiology. This case highlights the diagnostic limitations of current imaging and cytological techniques in identifying the precise nature of cystic neck masses. Despite suggestive features on imaging and FNA, a definitive diagnosis was not possible until surgical excision and histopathologic analysis. This underscores the difficulty in distinguishing between lymphatic malformations and branchial cleft anomalies preoperatively, particularly when radiographic and cytologic findings overlap, and reinforces the need for continued refinement of diagnostic algorithms.

As demonstrated here, the clinical presentation, imaging characteristics, and cytopathology findings can be nearly identical between the two diagnoses. Previous studies have consistently supported surgical excision as the primary treatment modality for cystic neck masses, particularly for microcystic and mixed lymphatic malformations.^1,2,7 Surgery not only provides therapeutic benefit but also is often necessary to establish a definitive diagnosis, especially when imaging is inconclusive or when malignancy remains in the differential. Surgical excision is generally associated with low morbidity and a favorable safety profile, with minimal variation in complication rates across different anatomical locations. ¹ However, special considerations must be made in cases involving comorbid conditions that increase procedural risk. In this case, the concurrent diagnosis of hemophilia B required a carefully coordinated perioperative plan to reduce bleeding risks, emphasizing the importance of a multidisciplinary approach. Otherwise, sclerotherapy has shown variable success depending on the lesion’s cystic architecture and location, with macrocystic lesions typically responding better than microcystic or mixed types. In adults, sclerotherapy may be used as a primary or adjunctive treatment modality; however, limitations include postprocedural swelling, pain, inflammation, and incomplete resolution, particularly for multiloculated or infiltrative lesions. For these reasons, surgical excision remains the preferred approach for well-circumscribed macrocystic lesions such as in this case. Current treatment recommendations are largely procedural, with both sclerotherapy and surgical excision used either alone or in combination depending on the clinical scenario.^2,7

Conclusion

Given the potential for diagnostic ambiguity and the risks associated with intervention, especially in patients with comorbidities such as hemophilia B, individualized and multidisciplinary care is essential. Collaboration between otolaryngology, hematology, radiology, and pathology allowed for a safe and effective treatment plan in this case. Ultimately, excision of the mass enabled us to establish a diagnosis as well as relieve the patient’s symptoms and remove the risk of future complications. As procedural management remains the cornerstone of treatment for lymphatic malformations, further research into minimally invasive approaches and standardized treatment protocols may help optimize outcomes while minimizing morbidity. This case is limited by its nature as a single case report.