CASE REPORT Numb-chin syndrome: an unusual presentation of metastatic prostate cancer A. THOMPSON, I. PEARCE, G. WALTON* and S.R. PAYNE Department of Urology, Manchester Royal In®rmary, *University of Manchester, Department of Maxillo-Facial Surgery, Manchester, UK Case report A 47-year-old man presented to the maxillo-facial unit complaining of numbness in the left side of his lower lip for 2 weeks, for which his dentist had been unable to ®nd a cause. Examination con®rmed altered sensation in the distribution of the inferior alveolar nerve on the left but excluded any intra-oral pathology. Radiological studies raised the possibility of a lucent lesion adjacent to the left alveolar canal (Fig. 1). Isotope scintigraphy revealed multiple areas of increased uptake throughout the skeleton, in keeping with widespread metastases (Fig. 2). His serum PSA level was 780 ng/mL and ALP 1108 IU/L. He was found to have a ®xed, frankly malignant prostate and underwent hormonal manipulation with GnRH analogues, after biopsy to con®rm the clinical diagnosis. This treatment provided a brief improvement in the numb chin, although disease progression led to death within 3 months. Comment Metastatic involvement of the mandible is rare but has been reported from several primary tumours, including prostate. However, 21 of 29 patients in two series [1,2] had a previously diagnosed primary malignancy. Numbness in the distribution of the alveolar nerve has been described as the `numb-chin syndrome' and should be regarded as being caused by malignancy within the mandible until proven otherwise [3]. In most cases there is associated mandibular pain, which is often intense, and hence altered sensation was the sole presenting symptom in only one of 17 patients [2]. To our knowledge this is the ®rst reported case of numb-chin syndrome as an isolated presenting symptom in widespread metastatic prostate cancer. References 1 Schwarz ML, Baredes S, Mignova FV. Metastatic disease to the mandible. Laryngoscope 1998; 98: 270±3 2 Glaser C, Lang S, Pruckmayer M et al. Clinical manifestations and diagnostic approaches to metastatic cancer of the mandible. Int J Oral Maxillofac Surg 1997; 26: 365±8 3 Lossos A, Siegal T. Numb chin syndrome in cancer patients: Etiology, response to treatment, and prognostic signi®cance. Neurology 1992; 42: 1181±4 Fig. 1. Ortho-pantomogram showing the lucent lesion in the left mandible (long arrows) and normal alveolar canal on the right (short arrows), through which the alveolar nerve passes. Fig. 2. Anterior bone scan images of the skull, thoracolumbar spine and pelvis, showing multiple areas of increased isotope uptake, including the left mandible. BJU International (2000), 85, 377±378 # 2000 BJU International 377