A Novel Intraoperative Technique Utilizing Suture to Identify Resection Margins and Acellular Dermal Matrix to Provide a Biologic Barrier During Diagnostic Salivary Surgery

Background: Acinic cell carcinoma (ACC) of the parotid gland is a rare pediatric salivary malignancy that often presents with benign imaging characteristics, leading to diagnostic uncertainty. This diagnostic ambiguity poses challenges for pre-operative planning and intra-operative decision making, as standard imaging modalities may not be reliable in distinguishing ACC from benign pathologies. Intraoperative discovery of possible malignancy requires safe and effective surgical decision-making to balance oncologic safety and preservation of normal structures. Case Presentation: We describe a 14-year-old female with a right parotid lesion initially presumed to represent a vascular malformation or branchial cleft cyst based on MRI and CT imaging. Intraoperatively, a firm solid mass was encountered, and frozen section analysis suggested a possible low-grade malignancy. To avoid premature extensive resection before definitive diagnosis, a novel intraoperative technique was employed: placement of an acellular dermal matrix (ADM) patch as a biologic barrier over the tumor bed, combined with 5-0 Prolene sutures marking 1 cm potential oncologic margins. Permanent pathology later confirmed acinic cell carcinoma, prompting a second operation for definitive resection after oncologic work-up. At time of definitive resection, the ADM and suture markings enabled precise identification of the prior tumor bed and margins, facilitating complete oncologic excision with negative frozen and permanent margins. The marginal mandibular branch of the facial nerve, found to be involved in the tumor, was repaired with nerve allograft. The patient recovered well without residual nerve deficits or recurrence on follow-up imaging. Conclusion: This case illustrates a novel staged surgical strategy using a biologic allograft and suture mapping to safely manage an indeterminate parotid lesion later confirmed as malignancy. This technique provides both an oncologic barrier and precise orientation for delayed definitive resection, representing a practical, reproducible approach when intraoperative pathology raises concern for malignancy in an otherwise presumed benign parotid mass.