Submandibular gland invasion and feasibility of gland-sparing neck dissection in oral cavity carcinoma.

OBJECTIVE: This study investigated the incidence and routes of submandibular gland involvement in oral cavity carcinoma to determine the feasibility of submandibular gland sparing neck dissection. METHODS: The records of 155 patients diagnosed with oral cavity squamous cell carcinoma, with a total of 183 neck specimens, including those involving level I, were reviewed retrospectively. RESULTS: Submandibular gland involvement, via direct invasion from the anatomical proximity of T4a tumours, was evident in two patients. The floor of mouth location, either primarily or as an extension of the primary tumour, was the only risk factor for submandibular gland involvement in oral cavity carcinoma (p = 0.042). Tumour location, clinical and pathological tumour (T) and nodal (N) stages, and radiological suspicion of mandible invasion, were not found to be statistically relevant (p > 0.05). CONCLUSION: The results suggest the feasibility of preserving the submandibular gland in early stage oral cavity carcinoma unless the tumour is located in, or extends to, the floor of mouth.

Patterns of cervical lymph node metastases in oral tongue squamous cell carcinoma: implications for elective and therapeutic neck dissection.

OBJECTIVES: To determine the patterns of lymph node metastases in oral tongue carcinomas, and examine the implications for elective and therapeutic neck dissection. METHOD: The study entailed a retrospective analysis of 67 patients with previously untreated oral tongue squamous cell carcinoma who had undergone simultaneous glossectomy and neck dissection. RESULTS: Of the 40 clinically node-negative patients, 7 patients had metastatic lymph nodes on pathological examination. No occult metastasis was found at level IV. Of the 27 clinically node-positive patients, the incidence rate of level IV metastasis was 11.1 per cent (3 out of 27 patients). No 'skip metastases' were found at level IV. Level IV metastases were significantly related to clinically staged nodes categorised as over 2a (p = 0.03) and metastasis to level III (p = 0.01). CONCLUSION: Routine inclusion of level IV in elective neck dissection is not necessary for clinically node-negative patients with oral tongue squamous cell carcinoma. Furthermore, extended supraomohyoid neck dissection with adjuvant radiotherapy can be sufficient in the treatment of selected patients with clinically node-positive necks.

TEOAE monitoring of Cisplatin induced ototoxicity in guinea pigs: the protective effect of vitamin B treatment.

OBJECTIVE: To evaluate Cisplatin (CP) induced ototoxicity and the effects of vitamin B treatment on ototoxicity in guinea pigs by using the Transient Evoked Otoacoustic Emission (TEOAE) technique. METHODS: Eleven guinea pigs were divided into two groups and they were tested by TEOAE before and after the experiment. A TEOAE response was regarded as positive when all of the following criteria were met: 1. The mean amplitude of the cochlear response in dB pe SPL should be greater than that of the noise in the external auditory canal; 2. The reproducibility rate of the response should be greater than 50%; 3. The stimulus stability rate should be greater than 65%; 4. The signal to noise ratio of the response in 1, 2, 3, 4 and 5 kHz band frequencies should be greater than 3 dB pe SPL in at least two bands. The first group included five animals that had only CP injections. Six animals in the second group received additional 0.2 ml/kg combined vitamin B preparations for 7 consecutive days. Thereafter, the right and left ears of all animals in both groups were tested by TEOAE. RESULTS: TEOAE responses recorded from 22 ears of 11 guinea pigs before drug administrations showed that the responses with maximum amplitude were originated from the mid-frequency region. Positive TEOAE responses were significantly reduced after CP administrations in both groups when compared with their respective pretreatment results (P<0.01). However, vitamin B injections, in addition to a single large dose of CP, resulted in significantly better TEOAE responses than those obtained after only CP injections (P<0.05). CONCLUSIONS: The routine use of TEOAE monitoring is recommended in clinical CP treatment protocols for the early detection and follow up of ototoxicity. Also, prospective clinical trials are needed in order to validate the protective effects of vitamin B treatment against ototoxicity.

Duplication of the parotid duct: a previously unreported anomaly.

A hitherto unreported duplication of the parotid duct in a 63-year-old man is reported. The ducts were found in the right cheek during cadaver dissection. The surrounding connective tissue of the ducts was removed and a photograph was taken. These two parotid ducts were then removed and fixed in a 10% formalin solution, embedded in paraffin blocks and the sections stained with hematoxylin eosin. The histologic findings showed that both had the normal ductal columnar epithelium. There was only one parotid duct in the left cheek.

Pharyngocutaneous fistula and total laryngectomy: possible predisposing factors, with emphasis on pharyngeal myotomy.

Ninety-two total laryngectomy cases were investigated with reference to post-laryngectomy fistula formation. Fistula was observed in eight cases (8.69 per cent). There were no statistically significant differences between the fistula group and the non-fistula group with regard to pre-operative tracheotomy, tumour differentiation, positive surgical margins, concurrent neck dissection, previous radiotherapy, T stage of the tumour, presence of extended hypopharyngeal mucosal excision, and placement of nasogastric tube. The only statistically significant positive association was found with primary pharyngeal myotomy. Myotomy was performed in six of the fistula patients and in two cases a technical error was observed. In these cases myotomy was performed adjacent to the edge of hypopharyngeal mucosa resulting in a weakened area of pharyngeal closure, possibly contributing to the fistula. This should be kept in mind and avoided at all costs during the performance of myotomy. Since it was not possible to find out any specific causal relationship with myotomy in four other cases, further studies are needed to establish the association of myotomy with pharyngocutaneous fistula.

Investigation of topical ciprofloxacin ototoxicity in guinea pigs.

Antibiotic eardrops mostly contain potentially ototoxic aminoglycosides. Ciprofloxacin is an alternative, and there is limited experience in its topical use. To investigate the topical ototoxicity of ciprofloxacin, 11 guinea pigs have been operated on. Transbullae silicone drug delivery tubes were placed to both ears of the animals. After the operation the guinea pigs were divided into two groups. The first group of animals received 0.2 ml of 4% gentamicin in one ear and 0.2 ml of 0.9% sodium chloride solution in the other. The second group received 0.2 ml of 0.2% ciprofloxacin in the test ear and 0.2 ml of 0.9% sodium chloride solution in the control ear. All drugs were given once a day on 7 consecutive days. Auditory brainstem response thresholds were recorded using click, 4 and 8 kHz logon stimuli before and after the operation, and after topical drug application. Results were statistically compared using Wilcoxon matched pairs signed-ranks test. Comparison of the thresholds before and after the operation, physiological saline application, as well as ciprofloxacin application yielded no statistically significant differences, whereas application of gentamicin resulted in total hearing loss. The results indicate that topical use of 0.2% ciprofloxacin is not ototoxic in guinea pigs.

Polymerase chain reaction in the diagnosis of parotid gland tuberculosis.

A parotid gland mass with presenting features of malignancy is a diagnostic and therapeutic challenge. The histological nature of the lesion must be clearly determined before proceeding with facial nerve sacrificing surgery. Although rare, tuberculosis of the parotid gland must be included in the differential diagnosis of a parotid gland mass especially when the social characteristics of the patient suggests a mycobacterial infection. Primary tuberculosis of the parotid gland is generally encountered among populations with a high incidence of pulmonary disease. The difficulty in the differential diagnosis of a parotid gland malignancy may be helped by a high degree of clinical suspicion, since laboratory tests generally do not identify the specific causative organism. This article reports the first case of parotid gland tuberculosis with clinical and radiodiagnostical features simulating malignancy in which the diagnosis was confirmed by the polymerase chain reaction (PCR).