title: [Adenolymphoma and microadenolymphoma. Histomorphogenetic considerations].
abstract: Histomorphogenetic considerations. Seventy three consecutive cases of parotid adenolymphoma were studied. Clinical data (age, sex, site, diagnostic hypothesis, type of surgery), macroscopy (examination of all nodules associated with adenolymphoma and related topography), microscopy (morphological analysis by means of conventional stainings, histochemistry, immunohistochemistry, semiquantitative and morphometric evaluations), with special regard to the lymphoid stroma, were correlated in order to investigate histo-morphogenetic aspects. In 44 cases, lymph nodes were detected (156:83 intraparotid and 73 periparotid). In 18 cases the adenolymphoma resulted multifocal. In 14 of them multifocality was due to the presence of only microscopic (clinically unsuspected) additional adenomas in intraparotid lymph nodes (20 microadenolymphomas). A further microadenolymphoma with 6 associated lymph nodes was occasional finding in a case of sialadenitis. Inclusions of salivary epithelium were observed in 46 intraparotid lymph nodes, were metaplastic (different types of metaplasia) in 23 of them, and were associated with 16 microadenolymphomas. Inclusions and microadenomas were both absent in periparotid lymph nodes. This study strongly supports the intralymphonodal histogenesis of the adenolymphoma and emphasizes the role of the ductal metaplastic changes of the salivary inclusions in the development of the adenomatous proliferation. A model of morphogenetic evolution (with related diagnostic problems) from intralymphonodal inclusions to microadenolymphoma and successively to clinical tumour (macroadenolymphoma) is proposed on the basis of the sequential rearrangement of the various morphological and morphofunctional observations. With special reference to the characteristics of the lymphoid stroma, a minor role of specific immunological mechanisms in the etiopathogenesis of the adenolymphoma is suggested.
authors.affiliation: Servizio di anatomia e istocitologia patologica, Ospedale E. Agnelli, (USSL 44) di Pinerolo, Torino.
authors.forename: R
authors.initials: R
authors.lastname: Vigliani
mesh_terms: D000235:Adenolymphoma / Q000473:pathology*; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D010307:Parotid Neoplasms / Q000473:pathology*
vernacular_title: Adenolinfoma e microadenolinfoma. Considerazioni istomorfogenetiche.