Introduction: Cystic neck masses in adult patients represent a significant diagnostic challenge, as they may conceal metastatic disease. Although cystic cervical metastases are most commonly associated with HPV-positive oropharyngeal squamous cell carcinomas, a cystic presentation does not exclude an HPV-negative etiology. The aim of this study is to highlight the importance of a systematic diagnostic approach, including panendoscopy with bilateral tonsillectomy, in the evaluation of cervical metastases of unknown primary origin. Case Report: We present a 47-year-old female patient with a painless cystic lesion in the left parotid region, initially interpreted radiologically as a benign lesion. Histopathological analysis following surgical excision revealed a cystic metastasis of squamous cell carcinoma with extracapsular extension and p16 negativity. Further diagnostic workup, including panendoscopy and bilateral tonsillectomy, identified synchronous bilateral HPV-negative tonsillar squamous cell carcinoma. Following bilateral selective neck dissection, adjuvant radiotherapy with concomitant chemotherapy was administered. At follow-up, there were no signs of disease recurrence. Conclusion: A cystic neck mass in adults should be considered malignant until proven otherwise. A negative radiological finding does not exclude the presence of a primary tumor in the oropharynx. This case highlights the diagnostic value of panendoscopy with bilateral tonsillectomy in identifying occult primary tumors, particularly in the context of HPV-negative disease.
Babić et al. (Thu,) studied this question.