2016, Volume 32, Number 1, Page(s) 035-039
Salivary Gland Tumors: A 15- year Report from Iran
Nasim TAGHAVI1, Soudabeh SARGOLZAEI1, Fatemeh MASHHADIABBAS1, Alireza AKBARZADEH2, Parisa KARDOUNI1
1Department of Oral Pathology, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, TEHRAN, IRAN
2Department of Basic Sciences, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, TEHRAN, IRAN
Keywords: Salivary gland,Tumor, Iran
The aim of this study was to document the clinicopathologic characteristic of salivary gland tumors in Tehran, Iran, over a 15-year
Material and Method: A retrospective study was conducted on salivary gland tumors diagnosed at two pathology centers of Shahid Beheshti
University of Medical Sciences from March 2000 to March 2015. Patient age, sex, tumor site and frequency, as well as clinical and radiographic
features and histopathologic diagnosis constituted the main analysis outcome measures.
Results: Of the 45429 biopsies conducted over 15 years, 6065 (13.3%) cases were oral and maxillofacial lesions and 937 (15.4%) of these had
tumoral diagnoses. Of the 937 tumoral cases, 184 (19.6%) were salivary gland tumors and among 184 cases, 65 (35.3%) were benign and
119 (64.7%) were malignant. Pleomorphic adenoma was the most frequently occurring tumor, comprising 32.6% of all tumors, followed by
mucoepidermoid carcinoma (27.1%) and adenoid cystic carcinoma (22.2%). Tumors were frequently reported in minor salivary glands (75%),
particularly in the palate with 89 (48.4%) cases. The peak ages of incidence were the fourth and sixth decades of life. Malignant salivary gland
tumors showed a predilection for females (72.9%), which was statistically significant (P<0.01).
Conclusion: The data presented herein are similar to previously published reports in other countries and other areas of Iran. However, some
differences were observed in our study, such as higher overall frequency, a lower mean age of patients with malignant tumors, and the particular
sites of involvement. These differences can be attributed to racial factors, the pathology centers of sample collection, and the duration of the studies.
The salivary gland system is composed of three pairs of
major glands and many lobules of minor salivary glands
that are scattered in the upper aero digestive tract, especially
in the oral cavity1
. Salivary gland neoplasms, though
uncommon, are remarkable for their diverse and complex
histologic features and various behaviors and prognoses.
These tumors account for 3-6% of all head and neck tumors2
. Less than 5% of salivary gland neoplasms occur in
patients under 16 years of age3
Epidemiologic studies have shown that the incidence and
subgroup distributions of salivary gland neoplasms vary
across the world, with diverse demographic results in
The aim of the present study was to evaluate the
epidemiologic characteristics of salivary gland tumors
(SGTs) during a 15-year period in Tehran, Iran based on
the 2005 WHO classification. Select data that are available from other provinces in Iran and other countries are also
compared and discussed.
The data in this retrospective and descriptive study included
records of the following 2 referral pathology centers of
Shahid Beheshti University of Medical Sciences in Tehran,
Iran: (a) the Oral and Maxillofacial Pathology Department
and (b) the Taleghani hospital. Patient records from March
2000 to March 2015, in which SGTs were diagnosed, were
Patient age, sex, tumor site and frequency, as well as
clinical, radiographic feature and histopathologic diagnosis
constituted the main analysis outcome measures. All
data was anonymous prior to analysis. This research was
approved by the ethics committee of Shahid Beheshti
University of Medical Sciences. Data were analyzed using
SPSS software (version 11.5).
Of the 45429 biopsies conducted over 15 years, 6065
(13.3%) cases were oral and maxillofacial lesions, and
937 (15.4%) of these had tumoral diagnoses. Of the 937
tumoral cases, 184 (19.6%) cases were SGTs. The overall
frequencies of benign and malignant tumors were 35.3%
and 64.7%, respectively. Pleomorphic adenoma (PA)
was the most frequently occurring tumor, comprising 60
cases, 32.6% of all tumors and 92.3% of benign neoplasms.
Mucoepidermoid carcinoma (MEC) was the most
frequently occurring malignancy and the second most
common tumor, representing 27.1% of all tumors and
42.01% of malignant tumors. There were 41 cases of adenoid
cystic carcinoma (ADCC) (22.2% of all tumors), which
made it the third most frequent tumor and the second most
common malignant tumor (34.4% of malignant tumors).
Tumors were more frequently reported in minor salivary
glands (73.9%), particularly the palate with 89 (48.4 %)
cases, followed by the parotid (14.6%).
Table I shows the distribution and location of the individual
neoplasms. Eight cases of intraosseous MEC (16% of all
MECs and 4.3% of all cases considered) were identified in
our series, and these cases mainly affected women (62.5%)
and particularly the posterior of the mandible (5 cases) for
patients with a mean age of 40.5 years. Interestingly, all cases of acinic cell carcinoma were diagnosed during the
second decade of life.
Click Here to Zoom
|Table I: Distribution and locations of benign and malignant salivary gland tumors
Regarding location, Fischer's exact test showed no
significant difference between benign and malignant
tumors (p = 0.301).
In terms of gender, 111 (60.4%) cases were female and 73
(39.6%) cases were male. Benign tumors showed a slight
predilection for males (53.8%), whereas malignant tumors
showed a predilection for females (72.9%). This difference
was statistically significant (p<0.01) and represented the
higher malignancy predilection in females.
The peak ages of incidence were the fourth and sixth
decades of life with mean ages of 41.2 and 45.5 years for
benign and malignant tumors, respectively (Table II). T-test
on individual samples revealed no significant difference
between the mean ages of benign and malignant tumors
The most significant sign of benign tumors was a painless
swelling, while rapid growth and ulcerative surface were
noted in malignant cases and especially high-grade tumors.
In 24 ADCC cases, the first significant sign was pain,
which has been associated with perineural invasion on
The predominant radiographic feature of intraosseous
MECs was ill-defined multilocular radiolucency.
The present study profiles SGTs in Tehran, Iran, according
to the 2005 WHO classification using cases taken from two
large university pathology centers over a 15-year period. Of
the 45429 biopsies reported, 184 cases (0.4%) were SGTs. In
previous reports from other Iranian, Nigerian and Mexican
groups, the percentages of SGT cases were 2.7%, 0.4% and
Moreover, the cases of SGTs evaluated in this study
constituted 19.6% of the oral and maxillofacial tumors
encountered, in contrast to the much lower ratios
(4.5%,2%) reported by other researchers2,7,8. However,
it is noteworthy that Pour et al.9 reported a ratio of 26.1%
for malignant SGTs in head and neck tumors.
The present study's evaluation of 184S GT cases indicates
that the majority of tumors were malignant, in contrast
to the results of most studies in west and south Iran and
other countries1,4,6,10-13 and in agreement with a few
In agreement with the results of Masanja et al.11, Ansari
et al.16 and Laishram et al.2 , we found an overall higher
frequency in females versus males which was statistically
significant. It should be considered that the male-to-female
ratio of benign tumors was 1.06: 1, whereas malignant
tumors had a male-to-female ratio of 0.45: 1, indicating
that benign tumors were slightly more common in males
and malignancies were more common in females. These
results are in agreement with previous studies of Tunisian
and Nigerian populations5,17, but are in contrast to
previously reported results in Brazilian, Turkish, Mexican
and Chinese populations6,10,18,19.
The patients' ages in current study varied from 11 to 79
years old, with a mean age of 41.2 years, in agreement with
other studies1,6,10,16,19. The mean age of patients
with malignant tumors did not differ significantly from the
mean age of patients with benign tumors, indicating that
the mean age of patients with malignant tumors had been
lowered in our series and the tumors can be seen in younger
patients, as found by Jansisyanont et al.20.
Most SGT cases (73.9%) originated in the minor salivary
glands, demonstrating a high frequency in the palate
(48.4%). The parotid (14.6%) was the second most
common SGT site, which is consistent with some previous reports (8,14,15) but not with others1,4,5,13,19,21-23.
In addition, 8 cases (4.3%) of central MEC were observed
in the present study and these mainly affected women
(62.5%) having a mean age of 40.5 years, similar to the Li
et al. report24. Moreover, the present study confirmed
previous reports that PA (32.6%) was the most frequently
occurring type of SGT1,2,4-6,10-13,16,19,21,25. The
next most frequently occurring tumor types were MEC
(27.1%) and ADCC (22.2%)13,14,16,19,26. In contrast,
in the Velazquez et al. and Wang et al. studies, Warthin's
tumor was the second most common tumor, followed by
malignant tumors6,21. In studies of populations in the
Congo, Jordan and Croatia, ADCC and MEC comprised
the second and third most common tumors, respectively22,27,28. However, Kamulegeya et al. studied an Ugandian
population and found that adenocarcinoma was the most
common malignant tumor29. In the present series,
adenocarcinoma constituted 5.9% of the SGTs encountered.
The most predominant clinical sign of benign tumors in
the present study was painless expansion, while pain, rapid
growth and ulcerative surface were observed in malignant
tumors, in accordance with previous studies2,3,9,30.
In conclusion, the data and results presented herein were
similar to previously published reports in other countries
and other areas of Iran. However, some differences were
observed, such a higher overall frequency, a lower mean
age of patients with malignant tumors and the particular
sites of involvement in our study. These differences can be
attributed to racial factors, the pathology centers of sample
collection and the duration of the studies.
1) Shishegar M, Ashraf MJ, Azarpira N, Khademi B, Hashemi
B, Ashrafi A. Salivary gland tumors in maxillofacial region: A
retrospective study of 130 cases in a Southern Iranian population.
Patholog Res Int. 2011;2011:934350.
2) Laishram RS, Kumar KA, Pukhrambam GD, Laishram S, Debnath
K. Pattern of salivary gland tumors in Manipur, India: A 10 year
study. South Asian J Cancer. 2013;2:250-3.
3) Bello IO, Salo T, Dayan D, Tervahauta E, Almangoush A,
Schnaiderman-Shapiro A, Barshack I, Leivo I, Vered M. Epithelial
salivary gland tumors in two distinct geographical locations,
Finland (Helsinki and Oulu) and Israel (Tel Aviv): A 10-year
retrospective comparative study of 2, 218 cases. Head Neck
4) Jaafari Ashkavandi Z, Ashraf MJ, Moshaverinia M. Salivary gland
tumors: A clinicopathologic study of 366 cases in Southern Iran.
Asian Pac J Cancer Prev. 2013;14:27-30.
5) Ochicha O, Malami S, Mohammed A, Atanda A. A histopathologic
study of salivary gland tumors in Kano, northern Nigeria. Indian
J Pathol Microbiol. 2009; 52:473-6.
6) Mejía-Velázquez CP, Durán-Padilla MA, Gómez-Apo E,
Quezada-Rivera D, Gaitán-Cepeda LA. Tumors of the salivary
gland in Mexicans. A retrospective study of 360 cases. Med Oral
Patol Oral Cir Bucal. 2012;17:e183-9.
7) Lee WH, Tseng TM, Hsu HT, Lee FP, Hung SH, Chen PY. Salivary
gland tumors: A 20-year review of clinical diagnostic accuracy at
a single center. Oncol Lett. 2014;7:583-7.
8) A deyemi BF, Ogun GO, Akang EE. Retrospective analysis of
intra-oral salivary gland tumours in Ibadan, Nigeria. West Afr J
9) Pour H, Zarei MR, Chamani G, Rad M. Malignant salivary
glands tumors in Kerman Province: A retrospective study. Dental
Research Journal 2007;4:4-10.
10) Kara MI, Göze F, Ezirganli S, Polat S, Muderris S, Elagoz S.
Neoplasms of the salivary glands in a Turkish adult population.
Med Oral Patol Oral Cir Bucal. 2010;15:e880-5.
11) Masanja MI, Kalyanyama BM, Simon EN. Salivary gland tumours
in Tanzania. East Afr Med J. 2003;80:429-34.
12) Morais Mde L, Azevedo PR, Carvalho CH, Medeiros L, Lajus T,
Costa Ade L. Clinicopathological study of salivary gland tumors:
An assessment of 303 patients. Cad Saude Publica. 2011;27:
13) Subhashraj K. Salivary gland tumors: A single institution
experience in India. Br J Oral Maxillofac Surg. 2008;46:635-8.
14) Tilakaratne WM, Jayasooriya PR, Tennakoon TM, Saku T.
Epithelial salivary tumors in Sri Lanka: A retrospective study of
713 cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod.
15) Poomsawat S, Punyasingh J, Weerapradist W. A retrospective
study of 60 cases of salivary gland tumors in a Thai population.
Quintessence Int. 2004;35:577-81.
16) A nsari MH. Salivary gland tumors in an Iranian population: A
retrospective study of 130 cases. J Oral Maxillofac Surg. 2007;
17) Moatemri R, Belajouza H, Farroukh U, Ommezzine M, Slama
A, Ayachi S, Khochtali H, Bakir A. Epidemiological profile of
salivary-gland tumors in a Tunisian Teaching Hospital. Rev
Stomatol Chir Maxillofac. 2008;109:148-52.
18) Fonseca FP, CarvalhoMde V, de Almeida OP, Rangel AL, Takizawa
MC, Bueno AG, Vargas PA. Clinicopathologic analysis of 493
cases of salivary gland tumors in a Southern Brazilian population.
Oral Surg Oral Med Oral Pathol Oral Radiol. 2012;114:230-9.
19) Li LJ, Li Y, Wen YM, Liu H, Zhao HW. Clinical analysis of salivary
gland tumor cases in West China in past 50 years. Oral Oncol.
20) Jansisyanont P, Blanchaert RH Jr, Ord RA . Intraoral minor
salivary gland neoplasm: A single institution experience of 80
cases. Int J Oral Maxillofac Surg. 2002; 31:257-6.
21) Wang YL, Zhu YX, Chen TZ, Wang Y, Sun GH, Zhang L, Huang
CP, Wang ZY, Shen Q, Li DS, Wu Y, Ji QH. Clinicopathologic
study of 1176 salivary gland tumors in a Chinese population:
Experience of one cancer center 1997-2007. Acta Otolaryngol.
22) A l-Khateeb TH, Ababneh KT. Salivary tumors in North
Jordanians: A descriptive study. Oral Surg Oral Med Oral Pathol
Oral Radiol Endod. 2007;103:e53-9.
23) E rgicho B, Ergisho B. Pattern of salivary gland tumors in Ethiopia
and non-western countries. Ethiop Med J. 2003;41:235-44.
24) Li Y, Li LJ, Huang J, Han B, Pan J. Central malignant salivary
gland tumors of the jaw: Retrospective clinical analysis of 22
cases. J Oral Maxillofac Surg. 2008;66:2247-53.
25) Otoh EC, Johnson NW, Olasoji H, Danfillo IS, Adeleke OA.
Salivary gland neoplasms in Maiduguri, North-Eastern Nigeria.
Oral Dis. 2005;11:386-91.
26) Targa-Stramandinoli R, Torres-Pereira C, Piazzetta CM,
Giovanini AF, Amenábar JM. Minor salivary gland tumors: A 10-
year study. Acta Otorrinolaringol Esp. 2009;60:199-201.
27) Kayembe MK, Kalengayi MM. Salivary gland tumors in Congo
(Zaire). Odontostomatol Trop. 2002;25:19-22.
28) Lukšić I, Virag M, Manojlović S, Macan D. Salivary gland
tumours: 25 years of experience from a single institution in
Croatia. J Craniomaxillofac Surg. 2012;40:e75-81
29) Kamulegeya A, Kasangaki A. Neoplasms of the salivary glands:
A descriptive retrospective study of 142 cases-Mulago Hospital
Uganda. J Contemp Dent Pract. 2004;5:16-27.
30) Sousa J, De Sa O. Salivary gland tumours: An analysis of 62 cases.
Indian J Cancer. 2001; 38:38-45.