Retroperitoneal metastatic squamous cell carcinoma of the tonsil (with elevated beta human chorionic gonadotrophin): a misdiagnosis as extra-gonadal germ cell tumour

Abstract

Head and neck cancers usually spread first to the regional lymph nodes but rarely may metastasize to distant sites. Metastasis to distant lymph node groups is a rare event. Furthermore, delayed multiple metastases without local recurrence is relatively uncommon. A case of retroperitoneal metastasis from a squamous cell carcinoma of the tonsil, secreting beta human chorionic gonadotrophin (beta-hCG), is reported. A 58-year-old man had undergone a tonsillectomy and chemo-radiotherapy for squamous cell carcinoma of the left tonsil and 13 months later presented with non-specific abdominal pain. The serum beta-hCG levels were high and an abdominal ultrasound scan revealed hydronephrosis on the left side. A computed tomography scan demonstrated para-aortic retroperitoneal lymphadenopathy. The patient underwent an open lymph node biopsy. The initial pathological analysis was interpreted as extra-gonadal germ cell tumour and the patient received chemotherapy. A subsequent review was consistent with a metastatic squamous cell carcinoma of the tonsil, as immunohistochemical studies showed positive staining for epithelial membrane antigen and cytokeratins 5/6 but a negative reaction to placental alkaline phosphatase. Following this, the chemotherapy regimen was changed; however, a restaging scan demonstrated progression, and the patient died from aspiration pneumonia secondary to alcohol intoxication. To our knowledge, this is the first reported case of retroperitoneal metastasis from a squamous cell carcinoma of the tonsil, secreting beta-hCG and causing hydronephrosis. This case highlights the necessity of using clinical, histological, immunohistological and ultrastructural examination to establish precise diagnosis and to avoid inappropriate treatment.