 |
| About Bioline | All Journals | Testimonials | Membership | News |
|
||||||
|
||||||
Journal of Cancer Research and Therapeutics, Vol. 5, No. 1, January-March, 2009, pp. 49-51 Case Report Numb chin syndrome as a manifestation of metastatic squamous cell carcinoma of esophagus Narendra H, Ray Satadru Department of Surgical Oncology, Kasturba Medical College, Manipal University, Manipal Code Number: cr09012 Abstract Numb chin syndrome (NCS) is a sensory neuropathy presenting with numbness of the chin in the distribution of the mental nerve and the branches of the mandibular division of the trigeminal nerve. Though it can be caused by a benign process, NCS should be regarded as being due to malignancy until proven otherwise. Among the malignancies that cause NCS the most common are breast cancer, prostate cancer, and lymphoreticular malignancy. In squamous cell carcinoma (SCC) of the esophagus, spread to the mandible is a rare and often late event. An often overlooked clinical sign in mandibular metastases is hypoesthesia or paresthesia over the peripheral distribution of the inferior alveolar nerve/mental nerve; this sign has been referred to in the literature as NCS or numb lip syndrome or mental nerve neuropathy. Rarely, this may be the first presentation of a disseminated malignancy. Prognosis is usually poor. The discovery of this symptom should alert the clinician to the possibility of disseminated disease. In this article we report a rare case of metastatic SCC of the esophagus in a 40-year-old male patient who presented with NCS. We also review the mechanism, causes, and evaluation of NCS.Keywords: Mandibular metastases, mental nerve neuropathy, numb chin syndrome, numb lip syndrome, squamous cell carcinoma of esophagus Introduction Numb chin syndrome (NCS) is a sensory neuropathy presenting with numbness of the chin in the distribution of the mental nerve and the branches of the mandibular division of the trigeminal nerve: i.e., the skin of the chin and the oral mucosa and the lower lip on the affected side. The cause of NCS may be 1) odontogenic, e.g., dental abscess, dental anesthesia, dental trauma, Osteomyelitis of mandible, and Odontogenic tumors; 2) systemic disease, e.g., amyloidosis, sickle cell disease, sarcoidosis, multiple sclerosis, HIV, and diabetes mellitus; and 3) malignant disease, e.g., lymphoma, breast cancer, leukemia, lung cancer, prostate cancer, and head and neck cancers. [1] This symptom could be the first manifestation of an incipient systemic cancer or could be an indication of the spread of an already established tumor. In either case, the prognosis is poor. [2] Hematogenous spread of squamous cell carcinoma (SCC) of the esophagus is known to occur to the liver, lungs, and bones. Bone involvement is a rare and late event. Hematogenous spread to bone of any malignancy generally occurs to the pelvis, vertebrae, ribs, and skull. The occurrence of metastasis to the jaws is rare. [3] Metastasis to the mandible can present with a local jaw swelling, a loose teeth, or pain. One of the typical presentations, which is under-appreciated, is hypoesthesia or paresthesia in the peripheral distribution of the inferior alveolar nerve/mental nerve; this has been referred to in the literature as NCS or numb lip syndrome or mental nerve neuropathy. To date only three cases of SCC of the esophagus with metastasis to the mandible and presenting with NCS have been reported. [4],[5] This paucity of reports in literature could be due to the rapid progression of the disease, with the patient succumbing before such dissemination occurs. The discovery of this symptom should alert the clinician to the the possibility of disseminated disease and thus help avoid unnecessary delay in the workup and treatment. In this article we intend to review the causes, mechanism, and evaluation of NCS occurring as a manifestation of metastatic disease. Case Report A 40-year-old male patient, who had earlier been diagnosed with cirrhosis of liver and portal hypertension (with a splenorenal shunt done 8 years back), presented to us with complaints of anorexia and dysphagia for solids for the past 3 months. General physical examination revealed pallor and bilateral pedal edema. Per abdominal examination was unremarkable, except for divarication of recti and ascites. The patient was suspected to have esophageal carcinoma and was admitted for further workup and treatment. Upper Gastrointestinal endoscopy revealed an ulceroproliferative growth at 25 cm from incisor, with significant luminal narrowing extending up to the cardia. Biopsy was taken, which was reported as moderately differentiated SCC. Ultrasonography abdomen and pelvis revealed ascites. Three days later, during his stay in the hospital, the patient started complaining of persistent tingling and numbness in the right side of the lower lip and the chin. On detailed enquiry, he admitted to having had this symptom for the past 1 month. An oral examination revealed a swelling in the gum in the region of the right lower second premolar and first molar (45, 46) teeth. A dental consultation was obtained for suspected dental infection. An orthopantomogram (OPG) revealed bone loss involving teeth 45, 46; there was an irregular trabecular pattern, with osteoblastic activity, in relation to the distal aspect of tooth 46 [Figure - 1]. On the basis of these findings, we suspected a metastatic lesion and an incisional biopsy from the gum was obtained, which was reported as moderately differentiated SCC. A whole-body bone scan was done, which showed increased radiotracer concentration over the head of the right femur, the angle of the left scapula, and the affected area in the right mandible [Figure - 2]. The chest x-ray was normal. A final diagnosis of SCC esophagus, with metastasis to bones, was made and the patient was referred for palliative treatment to radiation oncology services; however, the patient and his relatives were not willing for any treatment and he was discharged at request.Discussion The mental nerve is one of the terminal branches of the mandibular division of the trigeminal nerve. The mandibular division exits the base of the skull through the foramen ovale before branching. It passes through mandibular canal as the inferior alveolar nerve and exits the mental foramen in the horizontal ramus of the mandible as the mental nerve. The mental nerve supplies the skin of the chin and lower lip and the mucous membranes on the buccal surface of the lower lip. Involvement of the nerve by a malignant process gives rise to hypoesthesia or paresthesia over the peripheral distribution of the inferior alveolar nerve/mental nerve, which is referred to in the literature as numb chin syndrome or numb lip syndrome or mental nerve neuropathy. Metastasis to jaws, as compared to metastases to other bones, is extremely rare, constituting 1% of all metastases. These metastases originate most commonly from cancers of the breast (20-30%), thyroid gland (15%), kidneys (13%), lungs (12%), prostate (10%), gastrointestinal system (9%), and other organs (11-21%). [6] Bone involvement by hematological dissemination is seen in less than 10% of cases of SCC esophagus. Most mandibular metastases occur in the premolar and molar areas, where the presence of hematopoietic bone marrow and the slowing down of the circulation as a result of the anatomy of the region appear to favor the entrapment of the metastatic cells. [7] The clinical presentation of mandibular metastases can mimic common benign conditions such as toothache, temporomandibular joint pain, osteomyelitis, or trigeminal neuralgia. There may be swelling of the gum, loosening of a teeth, and pain. Though NCS is a well-described symptom of mandibular metastasis, it is under-appreciated by clinicians. The malignancies most commonly associated with NCS as reported in the literature include breast carcinoma, prostate adenocarcinoma, lung cancer, colon cancer, lymphoproliferative process, and multiple myeloma [Table - 1]. [2],[8] NCS commonly presents as numbness of the lip and chin, and occasionally of the gingivae and teeth, in the region supplied by the mental nerve. It may be the first symptom of a metastasis in the bone marrow of the mandible, but patients themselves rarely seek consultation for this complaint. [9] The mechanism of this syndrome may be peripheral (i.e., metastasis or invasion of mandible causing compression on the nerve) or central (i.e., due to base of skull lesions, leptomeningeal seeding, or perineural or neural invasion) or it may be a paraneoplastic syndrome. [2],[10] Though rare, a numb chin may be the first and only symptom of an underlying malignancy. [11] Symmetrical bilateral involvement has been reported in 10% of cases. [1] In a recent review of the subject, Gil et al . identified 16 studies with a total of 136 cases of malignant mental nerve neuropathy. Breast cancer (40.4%) and lymphoma (20.5%) were the most common malignancies responsible. NCS was the initial presenting symptom in 27.7% of cases and the first symptom of recurrent disease in 37.7%. [8] Evaluation of a numb chin in a patient with a known malignancy should include a thorough physical examination to rule out local causes, followed by OPG, CT scan or MRI, and whole-body bone scan. Imaging may be normal in patients with radiologically occult marrow infiltration or in those with a nonmetastatic neurological manifestation of malignancy. [8] Biopsy is often necessary to establish the diagnosis of malignancy. Lossos and Siegal reported that CT of brain, skull base, and mandible, along with cerebrospinal fluid analysis, would yield the diagnosis in 89% of patients with NCS and known malignancy. [8],[10] NCS should be regarded as being due to malignancy until proven otherwise. [11] It should never be dismissed as a 'trivial' symptom. [6] Usually, the presence of cancer elsewhere in the body is known before the numb lip develops (as in this case reported by us), but sometimes NCS may be the result of metastasis from an occult primary. Though the overall prognosis of patients with NCS is poor, the exact mechanism responsible for the syndrome determines prognosis. Median survival for patients with leptomeningeal tumor dissemination is longer compared to that for patients with direct mandibular metastases (12 months vs 5 months, respectively). [1],[10],[11] Gil et al . in their review of 16 studies reported a mortality of 78.5%, with a weighted mean survival of 6.9 months. [8] Nevertheless, prompt diagnosis may help in providing useful palliation and an improved quality of life. In conclusion, facial numbness in a patient with a known malignancy should alert clinicians to the possibility of metastatic bone disease. Imaging and biopsy should lead to the diagnosis. Treatment is purely palliative and consists of local radiotherapy References
Copyright 2009 - Journal of Cancer Research and Therapeutics The following images related to this document are available:Photo images[cr09012f2.jpg] [cr09012f1.jpg] [cr09012t1.jpg] |
| |||||||||
![[Figure - 1]](/showimage?cr/photo/cr09012f1.jpg){kind=link}
![[Figure - 2]](/showimage?cr/photo/cr09012f2.jpg){kind=link}
![[Table - 1]](/showimage?cr/photo/cr09012t1.jpg){kind=link}