Perineural invasion by carcinoma of the lower lip

Common conditions associated with mandibular canal widening: A literature review

Purpose

The aim of this study was to review the common conditions associated with mandibular canal widening.

Materials and Methods

General search engines and specialized databases including Google Scholar, PubMed, PubMed Central, Science Direct, and Scopus were used to find relevant studies by using the following keywords: “mandibular canal,” “alveolar canal,” “inferior alveolar nerve canal,” “inferior dental canal,” “inferior mandibular canal,” “widening,” “enlargement,” “distension,” “expansion,” and “dilation.”

Results

In total, 130 articles were found, of which 80 were broadly relevant to the topic. We ultimately included 38 articles that were closely related to the topic of interest. When the data were compiled, the following 7 lesions were found to have a relationship with mandibular canal widening: non-Hodgkin lymphoma, osteosarcoma, schwannoma, neurofibroma, vascular malformation/hemangioma, multiple endocrine neoplasia syndromes, and perineural spreading or invasion.

Conclusion

When clinicians encounter a lesion associated with mandibular canal widening, they should immediately consider these entities in the differential diagnosis. Doing so will help dentists make more accurate diagnoses and develop better treatment plans based on patients' radiographs.

Metastatic Squamous Cell Carcinoma of the Lower Lip: Analysis of the 5-Year Survival Rate

Objectives

The author analyse the impact of extracapsular lymph node spread and bone engagement in the ipsilateral neck of patients suffering squamous cell carcinoma (SCC) of the lower lip.

Methods

The data of 56 neck dissections performed in patients suffering SCC of the lower lip between January 2000 and December 2008 were retrospectively analysed. Statistical analysis was performed with the Kaplan-Meier life table method, and the survival rate was investigated with the log rank statistic and significance test. The values were considered statistically significant at p<0.05.

Results

Nine patients took advantage from simultaneous treatment of tumor and prophylactic neck dissection (level I-III), reaching 100% survival rate. Patients suffering metastasized disease, who received radical neck dissection at the time of tumor treatment, presented 83.3% survival rate. Patients who underwent previous surgery and radiotherapy presented worse prognosis although radical neck dissection in case of extra-capsular spread only (24.7%) and osseous engagement (22.2%).

Conclusion

Prophylactic neck dissection (level I–III) is recommended in T3–T4 N0 SCC. Simultaneous treatment of tumor and cervical lymph nodes provides a better prognosis as respect to delayed nodal management. Extra-capsular spread with or without bone engagement represents independent risk factor responsible for high mortality rate of SCC of the lower lip.

Mandibular Canal Widening and Bell's Palsy: Sequelae of Perineural Invasion in Oral Cancer

Perineural invasion is an underrecognized route of metastatic spread along the nerve bundles within the nerve sheath into the surrounding tissues. It hinders the ability to establish local control as tumour cells can traverse along nerve tracts well beyond the extent of any local invasion rendering them inoperable and unresectable. Perineural invasion is a marker of poor prognosis. Oral submucous fibrosis with oral cancer constitutes a clinicopathologically distinct disease. Our case highlights an enigmatic presentation of oral submucous fibrosis and its coexistence with oral cancer presenting with unusual neurological disturbance of the inferior alveolar nerve and facial nerve and diffuse widening of the mandibular canal. The objective of this case report is to enumerate the significance of perineural invasion in determining the course of the disease and necessitate the need for future studies that can shed light on molecular mediators and pathogenesis of perineural spread.

Minor salivary gland squamous cell carcinoma of the lower lip demonstrating striking perineural invasion

Squamous cell carcinomas (SCC) of minor salivary gland origin are extremely rare. We present an unusual case of a 29-year-old female patient who presented with a well-differentiated SCC of minor salivary gland origin arising in the lower lip. Wedge resections of the lip, including bilateral mental nerve excision, were required to clear the tumor because of striking pathological evidence of perineural invasion distant from the primary tumor site.

Brain metastasis from cutaneous squamous cell carcinoma of the dorsum

✓ The majority of cutaneous squamous cell carcinoma (SCC) are diagnosed early and cured using local treatment, although a minority of cases metastasize to regional structures. In this report the authors describe an unknown feature of skin SCC, namely, distant brain metastasis. This 54-year-old man, who had undergone surgery for moderately differentiated SCC of the dorsum (T2N0M0 stage), was admitted to our institution 11 months later with headache, vomiting, and ataxia. A magnetic resonance image documented a cerebellar lesion, which was totally removed. Results of histological studies revealed SCC. The patient received whole-brain radiotherapy (30 Gy over 2 weeks using a linear accelerator). A metastatic work-up showed enlarged inguinal and para-aortic lymph nodes that were histologically examined using excisional biopsy. Inguinal lymph nodes were tumor-positive and were dissected. The patient was subjected to two cycles of chemotherapy with cisplatin (75 mg/m2). After 3 months, a significant reduction in the size of the para-aortic lymph nodes was documented on control computerized tomography studies. Although the described case is unique, knowledge of the potential for this uncommon behavior in cutaneous SCC may be useful, especially because of its increasing incidence.

Perineural invasion of the lower alveolar nerve by oral cancer: a follow-up study of 12 cases

Twelve previously untreated cases of oral cancer with perineural infiltration were studied retrospectively. Age, sex, site, clinical stage and outcome were evaluated. Management of the neoplasm in each case involved surgical removal and six patients required adjuvant radiotherapy. The most frequent site was the lip. At the time of diagnosis, five patients had sensory complaints and palpable lymphadenopathy was observed in three patients. The 5-year crude survival rate was 16.7%. In the cases with postoperative assessment of perineural infiltration, a median survival time of 30.8 months was observed; while in the case of preoperative assessment of nerve infiltration, extensive surgery was performed with a consequent median survival time of 44.5 months. The perineural infiltration of the lower alveolar nerve is more common (6.3%) than is generally thought. This frequency is due to the relationship with the lower lip and the mandibular region. In carcinoma of the lip, spread is generally limited to 10-15 mm along the lower alveolar nerve. In carcinoma of the mandibular region, spread is entirely dependent on the location of the tumour; the absence of clinical fixation to the bone and the small size of the carcinoma does not preclude the possibility of bone involvement. Neurological symptoms should be evaluated carefully, and a radiographic investigation of the nerve canal is mandatory.