.

1. Epidemiology of salivary gland
tumours.
Including the relative frequency of
tumours at different sites.

2. According to literature;
salivary gland tumours are probably the most complex among human
neoplasia, due to their broad histological spectrum resulting from a
multiple tumour-cell differentiation, its cell arrangements and
extracellular matrix synthesis produced by certain tumour cells.
Dardick I, Burford-Mason AP, Garlick DS and Carney WP (1992)
Benign tumours are the most frequent types, corresponding to 54-79%
of these diseases, while malignant tumours account for 21-46% of
tumours.
Ribeiro KC, Kowalski LP, Saba LM, Camargo B (2002)

3. According to literature;
pleomorphic adenoma is the most common salivary gland tumour, once it
accounts for nearly 50% of all neoplasms occurring at this anatomical site.
Figueiredo et al., (2001)
The second most frequent condition is Warthin’s tumour, also called
papillary lymphomatous cystadenoma, corresponding to 4-14% of all
tumours.
Figueiredo et al., (2001)
the mucoepidermoid carcinoma, the cystic adenoid carcinoma and ex
adenoma pleomorphic carcinoma are very frequently found.
Ledesma-Montes C, Garces-Ortiz M (2002)

4. Relevant series published in literature showed that:
salivary neoplasms, either benign or malignant, are usually present in
greater salivary glands, specially the parotid (64-80%). When they
affect minor salivary glands, the palate is the most affected site.
Figueiredo et al., (2001)

5. Gender and Age
It was verified that, generally, both benign and malignant types were more
prevalent in women.
Peak incidence relative to age showed variations, with concentrations at the
third decade of life for benign tumours And the sixth decade for malignant
tumours.
Regarding race, there was little relevance due to lack of information from the
sources investigated.
Cantisano MH et al., (1998), Kayembe MK, Kalengayi MM (2002)

6. Gender and Age
• Prevalence (approximate): 1 per 100,000
• Age mainly affected: older adults
• Gender: F<M for benign / F=M for malignant
Diz Dios, P., 2016. Oral medicine and Pathology at a glance.
2nd ed. West Sussex: WILEY Blackwell, p.89

7. frequency of tumours at different sites
The parotid gland:
Is the single most common site for any salivary neoplasm, with about
70% of all tumours arising at this site of which about 85% are benign.
It is important to recognize that the frequency of benign lesions varies
by site. About 60% of submandibular, 50% of minor gland and only 10%
of sublingual lesions are benign.

8. Odell, E. and Cawson, R. (n.d.). Cawson's essentials of oral pathology and oral
medicine. 7th ed. London: Churchill Livingstone, p.263.

9. Diz Dios, P., 2016. Oral medicine and Pathology at a glance.
2nd ed. West Sussex: WILEY Blackwell, p.89
• Most tumour in the:
1- Parotid = benign
2- Lips = are in the upper lip and benign
3- Submandibular = 50% benign + 50% malignant
4- Sublingual = malignant
5- tongue = Malignant

10. (Speight & Barrett, 2002)
• Furthermore, at some sites benign lesions are very rare. In the tongue
and retromolar area virtually 100% of salivary neoplasms are
malignant.
• In the lips, most tumours (70%) are benign and basal cell and
canalicular adenomas are particularly frequent at this site.
• It should be noted that most labial salivary tumours are in the upper
lip. Neoplasms in the lower lip are relatively rare.

11. (Speight & Barrett, 2002)
In the minor salivary glands, reports suggest that polymorphous low
grade adenocarcinoma, which is becoming increasingly recognized, is a
common malignancy.
26% of minor salivary gland tumours were polymorphous low grade
adenocarcinomas. Waldron, El-Moftly and Gnepp (1988)
most common intraoral salivary gland malignancy in an African
population. Van Heerden and Raubenheimer (1991)

12. (Guzzo et al., 2010)
• Major salivary gland tumours
Malignant tumours comprise 15–32% of parotid tumours, 41–45% of
submandibular tumours and 70–90% of sublingual tumours.
• Minor salivary gland tumours
About one half of the tumours that arise in these glands are malignant. The
incidence of malignancy depends on the site of occurrence. In the palate the
rate is similar to that in the submandibular gland 40–60%.
But as one goes from the tongue to the floor of the mouth and sublingual
glands, the incidence increases up to 90%
Lopes MA, Kowalski LP and da Cunha SG (1999)

13. Regezi, J., 2012. Oral Pathology clinical pathological correlation. 6th ed.
Missoury: Elsevier, p.204.

14. pleomorphic adenoma
which comprises about half of all tumours and 65% of parotid gland
tumours. It is also the most common minor gland lesion representing
40% of intraoral tumours and about 50% of those on the palate.
Speight, P., & Barrett, A. (2002). Salivary gland tumours. Oral Diseases, 8(5), 229–40.

15. Malignant
1- The most common malignant salivary gland tumour is the
mucoepidermoid carcinoma, which comprises about 10% of all tumours and
35% of malignant tumours.
2- Adenocarcinoma is the second most common malignancy. However,
other reported series, which shows Adenoid cystic carcinoma as the second
most common malignant tumour with an incidence of about 20%.
Followed by
3- Acinic cell carcinoma which had an incidence of 17%.
Speight, P., & Barrett, A. (2002). Salivary gland tumours. Oral Diseases, 8(5), 229–40.

16. Study on 245 cases of salivary epithelial neoplasia by
(Lima, Soares, de Amorim, & de Almeida Freitas, 2005)
Findings:
• Benign neoplasia were more common than malignant ones, while pleomorphic adenoma was the
most frequent type.
• Regarding malignant neoplasia, cystic adenoid carcinoma followed by acinar-cell carcinoma and
mucoepidermoid carcinoma were the most frequently observed types.
• Considering the anatomical site, greater ‘major’ salivary glands, specially the parotid gland, were
the most affected both by benign and malignant neoplasia.
• Concerning patients’ gender, women were more frequently affected.
• Peak incidence relative to age was respectively the third and seventh decades for benign and
malignant neoplasia.
• Finally, a higher incidence was observed among Caucasians.

17. Diz Dios, P., 2016. Oral medicine and Pathology at a glance. 2nd ed.
West Sussex: WILEY Blackwell, p.88.

18. Remember the “rule of nines” !
• Nine out of ten tumours affect the parotid
• Nine out of ten tumours are benign
• Nine out of ten tumours are PSAs
Diz Dios, P., 2016. Oral medicine and Pathology at a glance.
2nd ed. West Sussex: WILEY Blackwell, p.89

19. References:
• Diz Dios, P., 2016. Oral medicine and Pathology at a glance. 2nd ed. West Sussex: WILEY Blackwell, p.88.
• Regezi, J., 2012. Oral Pathology clinical pathological correlation. 6th ed. Missoury: Elsevier, p.204.
• Odell, E. and Cawson, R. (n.d.). Cawson's essentials of oral pathology and oral medicine. 7th ed. London: Churchill Livingstone,
p.263.
• Guzzo, M., Locati, L. D., Prott, F. J., Gatta, G., McGurk, M., & Licitra, L. (2010). Major and minor salivary gland tumors. Critical
Reviews in Oncology/Hematology, 74(2), 134–148. https://doi.org/10.1016/j.critrevonc.2009.10.004
• Lima, S. S., Soares, A. F., de Amorim, R. F. B., & de Almeida Freitas, R. (2005). Epidemiologic profile of salivary gland neoplasms:
analysis of 245 cases. Brazilian Journal of Otorhinolaryngology, 71(3), 335–340. https://doi.org/10.1016/S1808-8694(15)31332-X
• Speight, P., & Barrett, A. (2002). Salivary gland tumours. Oral Diseases, 8(5), 229–40. https://doi.org/10.1034/j.1601-
0825.2002.02870.x