J Clin Pathol: first published as 10.1136/jcp.41.4.403 on 1 April 1988. Downloaded from J Clin Pathol 1988;41:403-409 Clinicopathological study of myoepithelial sialadenitis and chronic sialadenitis (sialolithiasis) G M KONDRATOWICZ,* LESLEY A SMALLMAN, D W MORGANt From the *Department ofPathology, The Medical School, The University ofBirmingham, and tthe Department ofOtorhinolaryngology, The Queen Elizabeth Hospital, Birmingham SUMMARY To determine any overlap in pathological features between myoepithelial sialadenitis and chronic sialadenitis/sialolithiasis histological sections from 69 cases of myoepithelial sialadenitis (MESA) (n = 7) and chronic sialadenitis/sialolithiasis (n = 62) were reviewed over a 10 year period. Three of the cases with MESA contained calculi and four of those originally diagnosed as chronic sialadenitis/sialolithiasis showed epimyoepithelial island formation. The presence of calculi should not rule out a diagnosis of MESA, particularly in the parotid gland where calculi are uncommon; as the incidence of MESA may very well be underestimated and diagnosed as chronic sialadenitis, these patients, who are at increased risk of developing lymphoma, could be lost to follow up. Myoepithelial sialadenitis (MESA) is characterised by obtained from the files of the department of path- the formation of epimyoepithelial islands accompan- ology, University of Birmingham and the department ied by chronic lymphocytic infiltration of the salivary of histopathology, General Hospital, Birmingham. copyright. parenchyma and often glandular atrophy. It has Sections stained with haematoxylin and eosin were largely superceded the earlier used term, benign lym- reviewed and the presence or absence ofepimyoepith- phoepithelial lesion, which was coined by Godwin in elial islands, ductal infiltration by lymphoid cells, and 1952.12 calcified material noted. Other features assessed were Although the histological picture ofwell established the prominence of lobular lymphoid infiltration, MESA is usually so characteristic that there is little presence or absence of germinal centres, intra-acinar difficulty distinguishing it from other types of and ductal acute inflammatory cells, lobular and http://jcp.bmj.com/ sialadenitis, we recently saw a case of MESA in which periductal fibrosis and atrophy, and epithelioid gran- the excised parotid gland tissue contained several uloma formation. Interval sections were cut in those calcified laminated calculi situated within dilated cases showing epimyoepithelial island formation. The ducts. This feature, which initially prompted some case notes of patients diagnosed as having MESA diagnostic confusion, led us to review all the cases of or chronic sialadenitis/sialolithiasis, in which MESA and chronic sialadenitis/sialolithiasis from our epimyoepithelial islands were found were reviewed files seen over the past 10 years. The aim of this study (table). on September 24, 2021 by guest. Protected was to determine the incidence of calculi in cases diagnosed as MESA and the incidence of Results epimyoepithlial islands in otherwise typical chronic sialadenitis. We were particularly interested in cases Histological sections from a total of 73 salivary glands which may represent the development of MESA in (56 submandibular, 17 parotid) were reviewed. Two pre-existing chronic sialadenitis and the possibility of submandibular glands and six parotid glands had been any overlap between these two types of disease. reported as MESA or Sjogren's syndrome. This included one patient with two excisions over a period of several years. Chronic sialadenitis/sialolithiasis had Material and methods been diagnosed in 54 submandibular glands and eight parotid glands; calculi were noted macroscopically, or Cases diagnosed as chronic sialadenitis, sialolithiasis, microscopically, or a definite clinical history of MESA, Sj6gren's syndrome, or lymphoma were sialolithiasis had been elicited in 29 (53%) of subman- dibular glands and three (38%) of parotid glands. Of Accepted for publication 14 October 1987 the remaining three salivary glands, one was clearly a 403 J Clin Pathol: first published as 10.1136/jcp.41.4.403 on 1 April 1988. Downloaded from 404 Kondralowicz, Smallman, Morgan Table Clinical details ofcases ofMESA and chronic sialadenitis/sialolithiasis Duration of Case Age Salivary gland(s) gland symptoms Associated Serology and other No (years) Sex excised (months) Calculi diseases relevant investigations Clinical diagnosis 1 68 F Parotid 12 Absent Rheumatoid arthritis RhF positive Sj6gren's syndrome 2 45 F Parotid 5 Present Mixed collagen disease RhF positive Sj6gren's syndrome (microscopic) autoimmune throm- ANF positive bocytopaenia Schirmer's test positive 3 54 F Parotid 12 Absent ANF positive Sicca syndrome Schirmer's test positive 4 52 F Submandibular 12 Absent Rheumatoid arthritis, ANF positive Sj6gren's syndrome pernicious anaemia, Schirmer's test positive Hashimoto's thyroiditis Coomb's test positive Lymphopaenia Thrombocytopaenia 5 60 F Submandibular 6 Absent Rheumatoid arthritis RhF positive Sj6gren's syndrome Schirmer's test positive 6 42 F Both parotids 12 Present RhF positive Sicca syndrome (microscopic) ANF positive Polyclonalhypergamma- globulinaemia 7 41 F Parotid 60 Present Rheumatoid arthritis RhF positive Sj6gren's syndrome 8 65 F Parotid 180 Present Sialolithiasis 9 77 F Submandibular 36 Present Sialolithiasis 10 57 F Parotid 6 Present Sialolithiasis 11 36 M Submandibular 240 Present Sialolithiasis copyright. 14. http://jcp.bmj.com/ on September 24, 2021 by guest. Protected '* . AS - 4Y a 5 a .-'-*W .a Fig I Typical epimyoepithelial island in established MESA. Fig 2 Fragmented calculus within remains ofintralobular Many infiltrating lymphoid cells have a centrocyte-like duct (case 2). morphology at higher magnification (case 5). J Clin Pathol: first published as 10.1136/jcp.41.4.403 on 1 April 1988. Downloaded from Clinicopathological study ofmyoepithelial sialadenitis and chronic sialadenitis (sialolithiasis) 40)5 -Inimqw , .-. ... , I ,- 0 'i .4i 4 i I. N, _t * _. A. d* . A.%A%_ .-Le, 4 , ,:- 1--we --v I. L9,.W Fig 3 Dilated duct denselv infiltrated by lymphoid cells and containing calcified material (case 6). copyright. granulomatous sialadenitis, probably sarcoidosis, and the parotid cases. Male to female ratios were about 1:1 in the two others there was a history of trauma or local and 2:3, respectively. A review of these cases showed tumour resection. that epimyoepithelial islands were found in two (4%) The mean age of patients with MESA was 59 years of the submandibular glands and in two (25%) of the http://jcp.bmj.com/ (range 43-68 years); all were women (table). parotid glands. Calculi were identified either macro- Epimyoepithelial islands were found in all eight cases scopically or microscopically in all four cases (table). (fig 1). In addition, calculi were present in three (38%) Epimyoepithelial islands were small and sparse in cases, one of which was noted macroscopically on these four cases but more typical examples were slicing glandular tissue as a 0-2 cm stone (case 7). In the usually identified by interval sections through the other two cases calcified material was noted within tissue blocks (figs 4-6). A lymphoid infiltrate in the dilated ducts on histological examination (fig 2). Apart epithelium of dilated ducts as seen in MESA was from epimyoepithelial islands, an important his- present in both parotid tissue samples but not in on September 24, 2021 by guest. Protected tological feature was the presence of dilated ducts submandibular tissue; otherwise, lymphoid infiltra- infiltrated by lymphoid cells. This was seen in six ofthe tion of ductal epithelium was conspicuously absent in eight cases (75%) and was pronounced in three of the cases of chronic sialadenitis/sialolithiasis. these. In those cases containing calcified material this Occasional intraductal lymphoid cells were also was characteristically within dilated ducts of this type present as part of a granulomatous infiltrate in two of (fig 3). A dense chronic lymphoid infiltrate was also four cases of chronic sialadenitis in which sparse present around ducts and within lobules, but in most epithelioid granulomas were noted. Acute inflam- cases occasional lobules were largely spared or com- matory cells within ducts or acini were rare in the pletely devoid of infiltration. Germinal centre forma- presence of epimyoepithelial islands, but particularly tion varied from abundant to absent, but was present common in those cases of chronic sialadenitis with in most cases (75%). No cases of salivary lymphoma definite calculi (41%). A prominent lobular lymphoid had been seen over the 10 year period. infiltrate was present in seven of 54 (13%) subman- The mean age ofpatients in the chronic sialadenitis/ dibular glands, previously reported as being chronic sialolithiasis group was 44-6 years (range 13-77) for sialadenitis/sialolithiasis, but this was usually less the submandibular cases, and 57 8 years (48-65) for prominent than in the cases of MESA. J Clin Pathol: first published as 10.1136/jcp.41.4.403 on 1 April 1988. Downloaded from 406 Kondratowicz, Smallman, Morgan Fig 4 Epimyoepithelial island infiltrated by lymphoid cells in patient with clinical diagnosis ofsialolithiasis (case 9). copyright. In the parotid gland specimens this feature was manifestations can occur. The exact relation between prominent only in those cases containing this primary form and the classic secondary form is not epimyoepithelial islands.