gms | German Medical Science

ESBS 2005: Skull Base Surgery: An Interdisciplinary Challenge
7. Kongress der Europäischen Schädelbasisgesellschaft & 13. Jahrestagung der Deutschen Gesellschaft für Schädelbasischirurgie

18. - 21.05.2005, Fulda

Numb chin as a manifestation of malignancy: a neglected syndrome in the otolaryngology literature?

Meeting Contribution

Suche in Medline nach

  • K. Rajkumar - Department of Otolaryngology/Head and Neck Surgery, Derriford Hospital, Plymouth, UK
  • H.S. Khalil - Department of Otolaryngology/Head and Neck Surgery, Derriford Hospital, Plymouth, UK
  • R.K. Mal - Department of Otolaryngology/Head and Neck Surgery, Southmead Hospital, North Bristol, UK

ESBS 2005: Skull Base Surgery: An Interdisciplinary Challenge. 7th Congress of the European Skull Base Society held in association with the 13th Congress of the German Society of Skull Base Surgery. Fulda, 18.-21.05.2005. Düsseldorf: German Medical Science GMS Publishing House; 2009. Doc05esbs61

doi: 10.3205/05esbs61, urn:nbn:de:0183-05esbs616

Veröffentlicht: 27. Januar 2009

© 2009 Rajkumar et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielfältigt, verbreitet und öffentlich zugänglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

Introduction

The first descriptions of mental nerve involvement by a metastatic breast tumour are attributed to Charles Bell in 1829 [1]. However, the term ‘numb chin syndrome’ (mental neuropathy) was first coined by Calverley and Mohnac in 1963 [2]. Numb chin syndrome (NCS) represents sensory loss and paresthesias involving half of the lower lip and chin. This may be produced by any pathological infiltrating process or trauma involving the mental nerve, the inferior alveolar nerve, the mandible, the mandibular nerve, the skull base or the leptomeninges. Occasionally the cause may be unknown and the presentation bilateral [2]. The syndrome may be iatrogenic, caused by dental anaesthesia, or caused by slow-growing benign processes that disrupt the function of the mental nerve [3]. The syndrome however, is usually indicative of underlying malignancy and sometimes denotes a poor prognosis [4].

This alarming syndrome is well described in the haematology, oncology, medical and dental literature. To our knowledge, the numb chin syndrome has not been previously described in the Otolaryngology literature.

Pathogenesis

The suggested mechanisms of numb chin due to malignancy include direct perineural invasion of tumour cells into the mental or inferior alveolar nerves, compression of these nerves by metastatic mandibular tumours and involvement of the Trigeminal nerve root by metastatic meningeal tumours including skull base metastases and leptomeningeal infiltrations [5], [6].

Methods

A literature search of Embase (1980 to September 2003) and Medline (1966 to September 2003) using the search terms ‘numb chin’, ‘mental nerve’ ‘neuropathy’ and ‘malignancy’ was carried out. We also reviewed the list of references of retrieved articles. The data of the individual cases presented in each article were collated including age, sex, presenting symptoms, pathology, treatment modality and outcome.

Results

All together, 43 articles in the English literature were identified including case reports and case series of cancer patients with numb chin syndrome. None of the identified articles was reported in an Otolaryngology journal. The total number of individual cases reported in these articles was 138 patients, 72 females and 66 males. The mean age of the patients was 45.6 years (range 9–77 years). Figure 1 [Fig. 1] shows the primary malignancy diagnosed. Breast cancer was the most common lesion (29%) followed by lymphoma (23.9%) and leukaemia (16.7%). The site of infiltration included the mandible, mental nerve, mandibular nerve, leptomeninges as well as unknown sites. In some patients, more than one site was involved with the metastases. Numb chin was the presenting symptom in 37% of patients, heralded a recurrence of malignancy in 19.6% and a symptom in established malignancy in 41.3% of patients. The vast majority of patients were treated with chemotherapy or a combination of chemotherapy and radiotherapy. 94 of the cases (68.1%) were reported to have died or presumed dead, the majority within the first year of onset of NCS. The outcome was unknown in 11 cases (7.9%) and the remaining 33 patients (24%) where alive at the time of reporting, though mostly with active disease.

Conclusions

Unilateral numbness of the lip or chin should prompt the Otolaryngologist to consider the diagnosis of NCS and to search for an underlying aetiology. If local dental disease is excluded, the possibility of metastatic cancer, usually breast cancer or lymphoma must be considered. Patients with NCS may be vulnerable to additional manifestations of metastases to the nervous system. A neurological evaluation of patients with NCS is therefore prudent. However, once NCS is diagnosed, the prognosis is very poor, and survival limited.


References

1.
Furukawa T. Charles Bell's description of numb chin syndrome. Neurology. 1988;38:331.
2.
Benito-Leon J, Simon Rogelio, Miera C. Numb chin syndrome as the initial manifestation of HIV infection. Neurology. 1998;50:511-2.
3.
Lesnick JA, Zallen RD. Numb chin syndrome secondary to metastatic breast disease. J Colo Dent Assoc. 1999;78(1):11-4.
4.
Burt RK, Sharfman WH, Karp BI, Wilson WH. Mental neuropathy (numb chin syndrome). A harbinger of tumour progression or relapse. Cancer. 1992;70(4):877-81.
5.
Hiraki A, Nakamura S, Abe K, Takenoshita Y, Horinouchi Y, Shinohara M, Shirasuna K. Numb chin syndrome as an initial symptom of acute lymphocytic leukaemia. Oral Surg Oral Med Oral Pathol. 1997;83(5):555-61.
6.
Laurencet FM, Anchisi S, Tullen E, Dietrich PY. Mental neuropathy: report of five cases and review of the literature. Crit Rev Oncol Hematol. 2000;34:71-9.