Retropharyngeal lymphatic malformations: report of two successfully treated cases and review of the literature

Successful Management of Retropharyngeal Lymphangioma with Stridor Using Sirolimus: A Case Report

Lymphatic malformations (LMs) are one of the congenital malformations of the lymphatic system in the body. The patient usually presents with head and neck swelling, airway compression, and/or airway obstruction. The diagnosis of retropharyngeal LMs can be challenging due to their rare occurrence. We report a case of a five-month-old boy diagnosed with retropharyngeal LMs. He presented with a three-day history of fever, cough, and stridor and was initially treated for acute bronchiolitis. A lateral neck radiograph revealed prevertebral widening, suggesting retropharyngeal collection. The patient's condition worsened, requiring intubation in the operating room and proceeding with aspirations and drainage. However, the symptoms recurred after a few days, necessitating re-intubation, repeated aspirations and drainage procedures. The patient was intubated, and the neck's magnetic resonance imaging (MRI) confirmed retropharyngeal LMs. An elective tracheostomy was performed and was treated with sirolimus. The patient had a successful tracheostomy decannulation and showed no recurrence during follow-up.

[Application of surgery combined with bleomycin irrigation for complex cervical-facial lymphatic malformations in children]

Objective:To present experience and evaluate the safety and efficacy of surgery combined with bleomycin irrigation for the management of head and neck lymphatic malformations in children. Methods:The medical records of all patients with cervical-facial lymphatic malformations who presented to Shanghai Children's Hospital from August 2014 to December 2020 were reviewed. 97 children were divided into surgery group（81 cases） and sclerotherapy group（16 cases）. Conventional contrast-enhanced magnetic resonance imaging（MRI） and B-ultrasound examinations were performed both preoperatively and postoperatively. The surgical group received lymphangioma resection combined with bleomycin irrigation. The sclerotherapy group was treated with B-ultrasound-guided percutaneous lymphangioma aspiration and bleomycin sclerotherapy. SPSS 21.0 software was used to evaluate the clinical cure rate and postoperative complications of lesions in both groups by chi-square test. Kaplan-Meier method was used to calculate the disease-free survival rate and draw survival curve. Results:In the surgery group of 81 children, 64 cases were cured and 17 cases were effective while in the sclerosis group, 8 cases were cured and 8 cases were effective. Cox proportional risk model found that children in the surgery group had a higher cure rate and a lower risk of 5-year recurrence than those in the sclerotherapy group, with statistically significant differences（χ²=5.814, P<0.05）. The risk of recurrence in the surgery group was 35.4% of that in the sclerotherapy group（HR=0.354, P<0.05）. In regards to postoperative complications, the surgical group had no higher rate of temporal facial paralysis and other nerve injuries compared to the sclerotherapy group（χ²=1.041, P=0.308）. Conclusion:Surgery combined with bleomycin irrigation in the complex cervical-facial lymphatic malformations was confirmed to be effectively and safely. The principle of the surgery was to protect the structure and function of normal tissue while excising the lesions as much as possible. When the lesions involved the posterior two-thirds of the tongue, the floor of the mouth, parapharynx, retropharynx, or hypopharynx spaces. Radiofrequency ablation was used in the surgical excision, which made the surgery more minimally invasive, accurate and personalized.

Recent Progress in Lymphangioma

Lymphangioma is a common type of congenital vascular disease in children with a broad spectrum of clinical manifestations. The current classification of lymphangioma by International Society for the Study of Vascular Anomalies is largely based on the clinical manifestations and complications and is not sufficient for selection of therapeutic strategies and prognosis prediction. The clinical management and outcome of lymphangioma largely depend on the clinical classification and the location of the disease, ranging from spontaneous regression with no treatment to severe sequelae even with comprehensive treatment. Recently, rapid progression has been made toward elucidating the molecular pathology of lymphangioma and the development of treatments. Several signaling pathways have been revealed to be involved in the progression and development of lymphangioma, and specific inhibitors targeting these pathways have been investigated for clinical applications and clinical trials. Some drugs already currently in clinical use for other diseases were found to be effective for lymphangioma, although the mechanisms underlying the anti-tumor effects remain unclear. Molecular classification based on molecular pathology and investigation of the molecular mechanisms of current clinical drugs is the next step toward developing more effective individualized treatment of children with lymphangioma with reduced side effects.

Endoscopy-assisted, transoral submucosal coblation for pediatric retropharyngeal lymphatic malformations

OBJECTIVE

Retropharyngeal lymphatic malformations (LMs) are uncommon congenital anomalies. Open surgery, sclerotherapy and various pharmaceutical agents have been described to manage these lesions. However, when such lesions involve the retropharyngeal space with evidence of airway compromise, none of the above aforementioned modalities has shown superior result without repeated imaging and procedures. We describe the use of radiofrequency ablation (Coblation) in an endoscopic-assisted, transoral approach as a one-off treatment for pediatric retropharyngeal lymphatic malformations.

METHODS

Six patients with retropharyngeal lymphatic malformations, presented with airway compromise, were treated with endoscopic-assisted, transoral submucosal coblation in our unit between April 2015 to August 2018. We retrospectively reviewed their medical records, imaging and endoscopic findings.

RESULTS

Five out of our six patients had LMs involving only the retropharyngeal space, who received the coblation as their sole treatment. One patient with extensive LMs involving multiple neck compartments received coblation to the retropharyngeal part as an adjunct procedure. The average operation time was 62.8 min, and the average intraoperative blood loss was 3.8 ml. All patients were safely extubated immediately after the surgery. None required admission to pediatric intensive care unit (PICU), nor prolonged dysphagia reported. They were observed for 2-5 days post operatively. The average follow up was 28 months (1-5 years) and none required re-operation to date.

CONCLUSIONS

We presented our approach and outcome of 6 children with endoscopic-assisted, transoral submucosal coblation to retropharyngeal lymphatic malformation. We believe it is a safe and effective primary treatment to these patients, and a possible adjunct to complex vascular malformation involving multiple sites.