CORRELATION OF HIGH LACTATE LEVELS IN HEAD AND NECK TUMORS WITH INCIDENCE OF METASTASIS

Using quantitative bioluminescence imaging, tissue concentrations of A TP, glucose, and lactate were register ed in biopsies that were taken from primary tumors of human head and neck at the time of first cancer diagnosis. From 15 patients investigated at present, 6 had locoregion al lymph none metastasis, 6 had no detectable metastatic spread 2 biop sies contained dysplasias, and I biopsy consisted exclusively of norma l mucosal and submucosal tissue. There was no correlation between stag ing or grading and any of the metabolic parameters measured. Mean lact ate concentrations (+/-SD) were significantly higher and scattered oz, er a wider range in tumors with metastatic spread (12.3 +/- 3.3 mu mol /g) in comparison with malignancies in patients without metastasis (4. 7 +/- 1.5 mu mol/g). Despite the low number of patients, these differe nces were statistically highly significant (P < 0.005; Mann-Whitney). Neither ATP nor glucose contents showed such a correlation with the em ergence of metastasis. Mean lactate contents of the two dysplasias wer e 0.1 and 3.5 mu mol/g; that of the normal tissue was 0.1 mu mol/g. Al though these findings have to be verified in a higher number of patien ts, the present data indicate that elevated lactate levels ill primary turners of head and neck may be associated with a high risk of metast atic spread. With the underlying mechanisms remaining to be investigat ed lactate imaging is possibly useful as an early indicator of the mal ignant potential of tumors in patients.