Objective To investigate the clinical pathological feature and diagnostic criteria of tongue amyloidosis（AL）. Methods During 1992 to 2005

25 patients pathologically diagnosed as tongue AL in our hospital were reviewed retrospectively

and all of them had no enlarged tongue. Haematoxylin and eosin （HE） and immunohistochemical staining were used to detect the amyloid deposition on the tongue. Results Totally 84% （21/25） patients had symptoms of xerostomia and taste-blindness

44% （11/25） patients complained of activity limitation of tongue. Macroscopic observation showed mucosa pallescence

punctuate hemorrhage

red grain particles

and ulcers on the tongue. HE staining indicated amyloid depositions in basement membrane

muscle cell

vessel wall

and nerve fiber. Immunohistochemical study demonstrated kappa light-chain deposition in 64% （16/25） cases

and lambda light-chain deposition in 36% （9/25） cases. They presented in vessel wall

nerve fiber

and muscle cells. Conclusion The biopsy is an important means for the diagnosis of early tongue AL

and the wide variety of amyloid light chain is helpful to differential diagnosis.