Buccal squamous cell carcinoma is an aggressive form of oral carcinoma with a high recurrence rate[i]. Iatrogenic parotid duct injury is often unavoidable in these cases due to the intimate anatomic relationship between the buccal mucosa, Stenson’s duct and the parotid gland. Preservation of duct function can be challenging following resection to achieve clear oncological margins.[ii] Sialocele formation is inevitable due to extravasation of saliva into the surgical defect which delays healing, creates fistulas and produces painful facial swelling. There is no consensus regarding the management of sialocele.[iii] Multiple authors have described varying modalities of treatment such as repeated percutaneous needle aspiration, pressure dressings, anti-sialogogue therapy, radiotherapy, botulinum toxin and surgical techniques including duct repair, diversion, ligation, use of drains, and parotidectomy. [iv] [v]We present 3 cases of parotid siaolcele and non-healing fistulas successfully treated with Botox (onabotulinumtoxin A) after tumor extirpation, neck dissection and reconstruction with a microvascular free flap.
Materials and Methods:
The aim of this case series is to share our experience with the use of BOTOX® (onabotulinumtoxin A) for the treatment of sialocele postoperatively after ablative and reconstructive surgery of buccal squamous cell carcinoma involving the Stenson’s duct. We reviewed 3 patients treated at the University of Texas Health Sciences Center at Houston Department of Oral and Maxillofacial Surgery, during a 5-month period between September 2014 and January 2015. Two patients presented with T4 N1 M0 and one patient with T4 N2a M0 buccal squamous cell carcinoma that required extirpation, modified radical neck dissection and reconstruction with a microvascular free flap. All 3 patients were presented at the University of Texas and Baylor College of Medicine multidisciplinary tumor board respectively. The surgical plan, postoperative radiation and chemotherapy were agreed upon. All surgeries were uneventful with negative margins and successful reconstruction with a microvascular free flap. In all 3 cases, facial swelling and increased WBC were noticed on post-operative day three. CT scans revealed siaolecele formation between the defect site and free flap. The patients were taken back to the OR for exploration and placement of Jackson-Pratt 10 round drains. A protocol of 50 mouse units was given subcutaneously over the parotid region after the placement of the drain. The drains were taken out once the output was less then 5cc for a 24 hour period.
No untoward side effects were appreciated after receiving 50 mouse units of Botox. In both patients, salivary flow decreased sufficiently to allow for flap healing and postoperative chemotherapy and radiation treatment. Ultimately, the effect of high dose radiation to the affected parotid completely resolved the problem.
The use of Botox and a temporary drain has shown to be an efficient and effective way of decreasing salivary flow for patients that have developed post-operative parotid salivary sialocele from head and neck oncologic surgery. In these cases, salivary gland flow decreased enough for the flap to heal without infection and to allow the patient to start radiation treatment, which would further atrophy the gland.
Lubek JE, Dyalram D, Perera EH, Liu X, Ord RA. A retrospective analysisof squamous carcinoma of the buccal mucosa: an aggressive subsitewithin the oral cavity. J Oral Maxillofac Surg 2013;71:1126–1131
Kulyapina A, Lopez-de-Atalaya J, Ochandiano-Caicoya S, Navarro-Cuellar C, Navarro-Vila C. Iatrogenic salivary duct injury in head and neck cancer patients: report of four cases and review of the literature. J Clin Exp Dent. 2014;6(3):e291-4.
Lewkowicz, Alberto A. et al. Traumatic injuries to the parotid gland and duct Journal of Oral and Maxillofacial Surgery , Volume 60 , Issue 6 , 676 - 680