Table 1. Summary of clinical and pathological data on the potentially malignant disorder (PMD) and oral squamous cell carcinoma (OSCC) cases included in this study.

		PMDs			OSCCs
		Overall	Female	Male	Overall	Female	Male
Number of cases		14	12	2	68	35	33
Average age (years)		70	73	50	69	72	65
Age (years)	Range	34–84	51–84	34–67	29–91	35–91	29–88
	< 30	0	0	0	1	0	1
	30–50	1	0	1	8	3	5
	50–70	5	4	1	26	14	12
	70 +	8	8		33	18	15
Number of patients who have never drunk or smoked		6	6	0	31	24	7
Anatomical location	Inner mucosa of lips	1	1	0	1	1	0
	Mobile part of the tongue	11	9	2	25	12	13
	Floor of the mouth				1	0	1
	Gum	1	1	0	26	16	10
	Cheek mucosa	1	1	0	7	2	5
	Intermaxillary region				4	1	3
	Hard palate of the mouth				3	2	1
	Soft palate of the mouth				1	1	0
	Hyperplasia	3	3	0	Not applicable
	Dysplasia Grade I	4	3	1
	Dysplasia Grade II	2	2	0
	Dysplasia Grade III	1	1	0
	In situ Carcinoma	6	5	1
Cellular differentiation	Well	Not applicable			38	17	21
	Medium				24	14	10
	Poor				5	3	2
Keratinization	Yes	Not applicable			47	23	24
	No				9	8	1
	Not Determined				12	5	7
Perineural invasion	Yes	Not applicable			26	14	12
	No				38	18	20
	Not applicable				4
Vascular embolus	Yes	Not applicable			13	9	4
	No				55	23	29
	Not applicable				3