1. Assoc. Professor Jan Laco, MD, PhD
Salivary gland tumors
Assoc. Professor Jan Laco, MD, PhD

2. General features incidence 0.4-13.5 (1.2) in 100,000
malignant SG tumors … 6 % head neck malignancies
55-80 % benign tumors
parotis (superficial lobe; %)  SM (7-11 %)  MSG (palate; 9-23 %)  SL
adults – years; more common in females
pleomorphic adenoma  Warthin tumor  mucoepidermoid carcinoma
etiology: irradiation (Japan, RTG), smoking (WT)

3. General features parotid submandibular MSG sublingual
78 % tumors of SG; 15 % malignant
submandibular
12 % tumors of SG; 30 % malignant
MSG
10 % tumors of SG; 45 % malignant
sublingual
0.3 % tumors of SG; 86 % malignant

4. Clinical features Benign tumor slow growth soft 85 % parotid tumors
NO skin ulceration
NO paresis n. VII
Malignant tumor
rapid growth, acceleration
± firm
45 % MSG tumors
± skin ulceration
± bone invasion
± paresis n. VII

5. Classification Benign tumors pleomorphic adenoma myoepithelioma
Warthin tumor
basal cell adenoma
oncocytoma
cystadenoma
ductal papillomas
Malignant tumors
mucoepidermoid carcinoma
acinic cell carcinoma
adenoid cystic carcinoma
polymorphous (low-grade) adenocarcinoma
carcinoma ex PA
carcinosarcoma
metastasizing PA
epithelial-myoepithelial carcinoma
salivary duct carcinoma

6. Diagnostics clinical features ultrasonography FNAC extirpation
!!! definite diagnosis and assessment of surgical margins - pathologist !!!

7. Pleomorphic adenoma “mixed tumor“, 75% of parotid tumors
slow growth (years), movable, ± multinodular, 2-5 cm
epithelial component
ducts, cords, tubuli, sheets, smt. keratinization
mesenchymal-like component
myxoid / chondroid, bone, fat, …
recurrence (3-6%) – multifocal, myxoid
myxoid consistence, variable tumor capsule thickness, often incomplete capsule, tumor cells within capsule
incomplete removal
malignant transformation (6 %) – carcinoma ex PA

8. Myoepithelioma 1.5 % SG tumors clinical features similar to PA
myoepithelial cells
spindle, plasmacytoid, epithelioid, clear
recurrence ( PA)
malignant transformation

9. Warthin tumor “papillary cystadenoma lymphomatosum“
3.5% of SG tumors (locally up to 30 %!)
almost exclusively in parotid; lower pole of superficial lobe
multicentric (12-20 %); bilateral (5-15 %)
smoking (8x increased risk); from LN inclusions ?
painless swelling, 2-4 cm, ½-3 years
encapsulated cystic nodule
bilayered oncocytic epithelium (luminal + basal cells)
lymphoid stroma
metaplastic variant (7 % of WT)

10. Basal cell adenoma 1-3 % SG tumors; parotid
basaloid cells + peripheral palisading
4 variants:
solid
trabecular
tubular
membranous – recurrence (25 %) !!! + skin cylindromas
canalicular adenoma – upper lip

11. Oncocytoma 1 % SG tumors predominant oncocytes + clear cell variant
oncocytosis
older patients
acinar / ductal
disperse / focal / multifocal

12. Cystadenoma 4-5 % SG tumors, more common in MSG multicystic (80 %)
+ oncocytic variant
papillary x mucinous variants

13. Ductal papillomas 1. inverted ductal papilloma
lower lip, cheek, 2 cm
2. intraductal papilloma
lips, cheek, 2 cm
3. sialoadenoma papilliferum
palate
recurrence – % !!!

14. Mucoepidermoid carcinoma
most common SG malignant tumor
parotid (45 %) + SM + MSG (palate, cheek)
epidermoid + mucinous + intermediate cells
histopathological grade (WHO 2005):
cystic component < 20% … 2
neural invasion … 2
necroses … 3
 4 mitoses / 10 HPF … 3
anaplasia … 4
LG - 0-4; IG - 5-6; HG - >6
lymphogennous metastases; prognosis usually good

15. Acinic cell carcinoma parotid (80 %) + MSG (17 %), 1-3 cm
acinic cell differentiation + other cell types
± lymphoid infiltrate (better prognosis ?)
4 variants:
solid
microcystic
papillary-cystic
follicular
recurrence – 35%

16. Adenoid cystic carcinoma
“cylindroma“
10 % of SG tumors; parotid + SM + MSG
ductal and myoepithelial (basaloid) differentiation
perineural spread
3 variants:
tubular
cribriform (seeve-like) – most common
solid – worse prognosis
recurrence – up to 85%
5-year survival - 35% x 10-year survival – 10-20%
lymphogennous + hematogennous (lungs) metastases

17. Polymorphous (low-grade) adenocarcinoma
common MSG malignant tumor
palate (60 %)
painless ulcer
cytologically uniform x polymorphous architecture
dif. dg. ACC
relatively good prognosis

18. Carcinoma ex PA 4 % SG tumors; 12 % SG malignant SG tumors
complication of approx. 6 % PAs
PA duration more than 3 years (usually to 10 years)
1-25 cm
malignant transformation of epithelial PA component
poorly differentiated adenocarcinoma (SDCa)
classification
intracapsular (non-invasive, in situ) – good prognosis
minimally invasive – good prognosis
invasive – poor prognosis

19. Carcinosarcoma extremely rare
malignant transformation of both epithelial
and mesenchymal PA component

20. Metastasizing PA microscopically like PA
dg. in retrospect in case of metastasis
skeleton, lungs, lymph nodes
variable interval (1-55 years)

21. Epithelial-myoepithelial carcinoma
1 % SG tumors, females
epithelial cells (ducts) + rim of clear myoepithelial cells
recurrence – 40 %

22. Salivary duct carcinoma
9% of SG malignant tumors, old pts.
similar to DIC of breast
variants:
spindle cell
mucinous
invasive micropapillary
angioinvasion and perineural spread
poor prognosis

23. Newly described entities and tumors
Sclerosing polycystic adenosis
Secretory carcinoma (MASC)
Cribriform adenocarcinoma of MSG/tongue

24. Genetics Mucoepidermoid carcinoma Adenoid cystic carcinoma
t(11;19) …CRTC3-MAML2
Adenoid cystic carcinoma
t(6;9) … MYB-NFIB
Secretory carcinoma
t(12;15) … ETV6-NTRK3
Clear cell carcinoma
t(12;22) … EWSR1-ATF1

25. Mesenchymal tumors
hemangioma
congenital, childhood
lipoma

26. Hematologic malignancies
parotid (75 %), older patients
MALT lymphoma
extranodal marginal zone B-cell lymphoma
background of lymphoepithelial sialadenitis (SS)
good prognosis
FL, MCL, DLBCL

27. Secondary tumors = metastases 5 % malignancies
parotid + intra-/peri-glandular LN
carcinomas of lungs, breast, kidney
squamous cell carcinoma
melanoma

28. Tumors of childhood Sialoblastoma Salivary gland anlage tumor
very rare (23 cases), from blastematous cells?
congenital / early childhood
boys : girls (2 : 1); parotid
recurrence (22 %), metastases (9 %)
Salivary gland anlage tumor
very rare (approx. 20 cases), embryologic development
newborns, boys : girls (4 : 1)
polypoid midline tumor in nasopharynx, 1-3 cm
benign x suffocation !!!