cancer

Clinical presentation and diagnosis of oral cancer
• Early diagnosis of oral cancer ishould lead to better  treatment results and, ideally, the Clinical diagnosis of oral cancer should be easy.
The tongue
• The majority of tongue cancers occurs on the  middle third of the lateral margins. extending early in the course of the disease on to the ventral aspect and floor of the mouth
• Approximately 25 per cent occur on the posterior thirdof the tongue, 20 per cent on the anterior third and rarely  on the dorsum.
 • Early tongue cancer may manifest in a variety of ways. Often the growth is exophytic with areas of ulceration. It may occur as an ulcer in the depths of a fissure or as an area of  superficial ulceration with unsuspected infiltration into the underlying muscle.
 • Leucoplakic patches may or may not be associated with the primary lesion. A minority of tongue cancers may be asympromatic, arising in an atrophic depapillated area  with an erythroplakic patch with peripheral streaks or areas of leucoplakia.
• Later in the course of the disease a more typical malignant ulcer will usually develop, often several centimetres in diameter.
• The ulcer is  hard in consistency with heaped.up and often everted edges. The floor is granular, indurated and bleeds readily. Often there are areas of necrosis.
• The growth infiltrates the tongue progressively causing increasing pain and difficulty with speech and swallowing.
• By this stage pain is often severe and constant, radiating to the neck and ears.
• Lymph node metastases at this stage are common - indeed 50 per cent may have palpable nodes at presentation.
• Because of the relatively early lymph node metastasis of tongue cancer, 12 per cent of patients may present with no symptoms other than 'a lump in theneck'.


The floor of the mouth
• The floor of the mouth is the second most common sire for oral cancer.
• It is defined as the U-shaped area between the lower alveolus and the ventral surface of the tongue; carcinomas arising at this sire involve adjacent structures very early in their natural history.
• Most tumours occur in the anterior segment of the floor of the mouth to one side of the midline.
• The lesion usually starts as an indurated mass which soon ulcerates.
• At an early stage the tongue and lingual aspect of the mandible become involved. This early involvement of the tongue leads to the characteristic slurring of the speech often noted in such patients.
• The infiltration is deceptive but may extend to reach the gingivae, tongue and


genioglossus muscle. Subperiosteal spread is rapid once the mandible is reached.
• Lymphatic metastasis, although early, is less common that with tongue cancer.spread is usually to the submandibular and jugulodigasrric nodes and may be bilateral. 
• Cancer in the floor of the mouth cancer is associated withe a pre-existing leucoplakia more commonly than at other sites.
The gingiva and alveolar ridge
• Carcinoma of the lower alveolar ridge occurs predominantly in the premolar and molar regions
• The patient usually presents with proliferative tissue at the gingival margins or superficial gingival ulceration. • Diagnosis is often delayed because there is a wide variety of inflammatory and reactive lesions which occur in this region in association with the teeth or dentures. indeed, there will often be a history of tooth extraction with subsequent failure of the socket to heal prior to definitive diagnosis.
The buccal mucosa
• The buccal mucosa extends from the upper alveolar ridge down to the lower alveolar ridge and from the commissure anteriorly to the mandibular ramus and retromolar region posteriorly
• Squamous cell carcinomas mostly arise either at the commissure or along the occlusal plane to the retromolar area, the majority being situated posteriorly. Exophyric, ulcero-infiltrative and verrucous types occur.
• The onset of the disease may be insidious, the patient sometimes presenting with trismus due to deep neoplastic infiltration into the buccinaror muscle.
• Extension posteriorly involves the anterior' pillar of the fauces and soft palate with consequent worsening of the prognosis.
• Ulcero-infiltrative lesions will often involve the le overlying skin of the cheek resulting in multiple sinuses. Lymph node spread is to the submental, submandibular, parotid and lateral pharyngeal nodes.
• Verrucous carcinoma occurs as a superficial proliferative exophytic lesion with minimal deep invasion and induration. Often the lesion' is densely keratinised and presents as a soft white velvety area mimicking benign hyperplasia.
• Lymph node metastasis is late and the tumour behaves as a low-grade squamous cell carcinoma.
The hard palate, maxillary alveolar ridge and floor of antrum
• These three sites are anatomically distinct, but a carcinoma arising from one site soon involves the others
• Consequently, it can be difficult to determine the exact site of origin. Except in countries where reverse smoking is practised, cancer of the plate is relatively uncommon.