Solitary cystic masses in the lateral neck can present a significant diagnostic dilemma. These cystic masses often develop in young adults distinguishing a branchial cleft cyst from a cystic lymph node with imaging and even high-quality fine needle aspiration cytology (FNAC) can be impossible. Surgical excision and histological diagnosis is often the only way to obtain a definite diagnosis. The incidence of metastatic squamous cell carcinoma (SCC) in these can be as high as 22%. Usually, these are metastatic from tumours from the oro or nasopharynx and are often human papillomavirus (HPV) related. The effect of lymph node biopsy (including core needle biopsy) prior to definitive treatment is unclear, but in the absence of any clear evidence, a negative effect should be assumed. This paper addresses this issue by retrospectively study all patients presenting to a university hospital in Germany, from September 2011 until November 2013. Patients with a clinically apparent tumour were excluded and 131 patients were included in the study. All 69 male and 62 female patients had a full preoperative examination including ultrasound examination of the neck. In 58 patients ultrasound scan (USS) guided FNAC was performed – all these were reported negative for malignancy and supported a diagnosis of a cystic lesion. Twenty-five patients had already had imaging (elsewhere) reported as no signs on malignancy. All 131 patients went on to have surgical excision of the neck lump, 12 (9.2%) had a malignant tumour. HPV DNA was detected in all examined cystic tumours. All patients with a malignant disease went onto have panendoscopy, bilateral tonsillectomy and biopsies on the tongue base and nasopharynx. A primary tumour was only detected in 10 cases. None were detected on FNAC or ultrasound. No patient had a positron emission tomography-computed tomography (PET CT). The authors conclude that in patients aged 40 and older presenting with a solitary lateral neck mass a carcinoma is expected in 22% of cases. Interestingly, 90.8% of lateral cervical cysts were HPV negative but all lateral cystic metastatic lymph nodes showed HPV association. Thus, a solitary lateral cyst with HPV DNA is likely to a metastasis of an HPV associated SCC. This is a good short paper and reminds the reader of the complexity of diagnosis of a solitary cervical cystic mass