ORIGINAL ARTICLE

Oral Pathology

Analysis of salivary secretor status in patients with oralsubmucous fibrosis: a case-control studyKaveri Hallikeri1, Ravichandra Udupa1, Krutika Guttal2 & Venktesh Naikmasur2

1 Department of Oral and Maxillofacial Pathology, Sri Dharamasthala Manjunatheshwara College of Dental Sciences & Hospital, Dharwad,

Karnataka, India

2 Department of Oral Diagnosis and Radiology, Sri Dharamasthala Manjunatheshwara College of Dental Sciences & Hospital, Dharwad,

Karnataka, India

Keywords

blood group, carcinoma, oral submucous

fibrosis, saliva, secretor status.

Correspondence

Dr Kaveri Hallikeri, Department of Oral and

Maxillofacial Pathology, S.D.M. College of

Dental Sciences and Hospital, Sattur

Dharwad, Karnataka 580009, India.

Tel: +91-0836-2468142

Fax: +91-0836-2467612

Email: drcauveri2005@gmail.com

Received 11 October 2013; accepted 4 March

2014.

doi: 10.1111/jicd.12100

AbstractAim: Many individuals have various tobacco-related habits, yet only some

develop clinical manifestation of lesions. This raises the question of whether

there any inherent or host risk factors involved in the pathogenesis which need

to be further investigated. The aim of the present study was to analyze the

ABO antigen, secretor status, and blood groups of patients.

Methods: The study consisted of 99 participants, with 33 patients allocated to

three groups: (a) patients with a tobacco-related habit and oral submucous

fibrosis (OSF); (b) patients with a tobacco-related habit, but no lesions; and

(c) healthy controls. A total of 1 mL unstimulated saliva was collected in a

sterile test tube, and the Wiener agglutination test was performed to analyze

the ABO antigen in all three groups.

Results: All of the OSF patients were non-secretors, whereas 84.8% were non-

secretors in the group of individuals with habits as compared to 15.2% in the

healthy group. A statistically-significant difference was observed between the

OSF and healthy groups. The patients in the OSF group were predominantly

blood-group A, followed by groups O, B, and AB.

Conclusion: There is a correlation between salivary secretor status and the

development of OSF. Thus, non-secretors are at greater risk of and more prone

to the development of oral lesions. Blood-groups A and O predominate over

the B and AB blood groups.

Introduction

Oral submucous fibrosis (OSF) is a high-risk precancer-

ous condition related to chewing areca nut alone or as a

component of betel quid. Approximately 600 000 000

people worldwide chew raw areca nut or in any processed

form.1 In India, there is increasing addiction tendency

among young people due to easy access of tobacco prod-

ucts, effective price changes, and marketing strategies.

There are numerous commercially-prepared areca nut

preparations, and gutkha is the most popular. Recent epi-

demiological data indicate that the number of OSF cases

has increased rapidly in India from an estimated 250 000

cases in 1980 to 2 000 000 cases in 1993.2 This disease

has become a major public health issue in India, owing to

its prevalence among 20–30 year olds, and its association

with malignant transformation.

OSF is an irreversible condition; once developed there is

no effective treatment. The malignant transformation rate

associated with OSF ranges from 7% to 13%.3 More than

2400 new cases of oral cancer arising from OSF are diag-

nosed every year in Taiwan due to the prevalent use of

betel quid.4 Jian et al.5 analyzed the clinical symptoms and

signs in 29 cases of OSF cases, which transformed

into squamous cell carcinoma. Andakumar et al. and

Ko et al.6,7 reported a malignant transformation rate of

4–30.4% in India and 12.28% in Taiwan, respectively. Recent

data show that the potential of malignant transformation

ª 2014 Wiley Publishing Asia Pty Ltd 1

Journal of Investigative and Clinical Dentistry (2014), 5, 1–6

in OSF is much higher compared to other premalignan-

cies.8 Therefore, early diagnosis of this potentially-malig-

nant oral lesion is essential for better prognosis.

Although biopsy is the gold standard to observe the

earliest changes in the epithelium of premalignant lesions,

repeat biopsies might not be feasible. To overcome these

problems, the salivary secretor status would be useful. It

has been reported that non-secretor individuals are more

prone to develop lesions, and certain types of cancers are

more prevalent in particular blood-group types. Various

authors have shown the relationship between the patho-

genesis of disease and secretor status, which is a possible

factor influencing disease status.9,10 A higher intensity of

oral disease is found among non-secretors in terms of

precancerous and cancerous changes to tissues of the oral

cavity. Oral disease susceptibility is reflected in the occur-

rence of epithelial dysplasia, which was found almost

exclusively in the non-secretor group. The presence of the

epithelial antigen has a protective role in infections by

interfering with the binding sites either on the surface of

microorganisms or to epithelial cells. Studies have shown

that infection is more common in non-secretors.11,12 It

has also been reported that individuals with blood-group

A have a predisposition for oral cancer. The functional

loss of the A enzyme in dysplasia and carcinoma has been

reported, whereas in normal epithelium it is strongly

positive. This is due to the downregulation of glycosyl-

transferase, which is involved in the biosynthesis of A and

B antigens, and is associated with tumor development.13

Based on this, the present study was undertaken in order

to determine secretor status and blood group in OSF

patients and those with a tobacco-related habit without

lesions, and healthy controls.

Materials and methods

Salivary secretor status was studied in 99 individuals; each

group consisted of 33 patients: (a) patients with a

tobacco-related habit and OSF (group I); (b) patients

with a tobacco-related habit, but no lesions (group II);

and (c) healthy controls (group III).

Establishing secretor status in saliva

The methodology followed for assessment was adapted

from Vidas et al.14 A total of 1 mL non-stimulated saliva

was collected from each patient and stored in a sterile

glass vial. The saliva was then poured into a sterile test

tube and closed with a lid. The test tube was then placed

in boiling water bath for approximately 10 min to destroy

enzymes. The supernatant fluid was then extracted by a

centrifugal force of 1700 turns in 10 min. The Wiener

agglutination test was used to establish secretor status.

The test serum was diluted in a salted physiological solu-

tion of 1:10 dilution. The following antiserum was then

placed into test tubes marked I–IV: (a) I, one drop of sal-

iva + one drop of antiB serum; (b) II, one drop of saliva

+ one drop of antiA serum; (c) one drop of physiological

solution + one drop of antiB serum; and (d) one drop of

physiological solution + one drop of antiA serum.

After 10 min at room temperature, one drop of 2–3%of suspension A erythrocytes was added into sterile tubes

II and IV, and one drop of suspension B erythrocytes into

tubes I and III. All the test tubes were agitated, and left at

room temperature. Readings were available after 1 h. Test

tubes III and IV (controls) showed agglutination. Aggluti-

nation in tube I was as a result of the presence of sub-

stance A2 in saliva, that is, of secretor A, while the

agglutination in tube II was proof of secretor B. The

absence of agglutination in tubes I and II designated AB

secretor, and at the same time, agglutination in tubes I

and II confirmed that the person was a non-secretor.

Results

The type and distribution of tobacco-related habits and

the detailed percentages among the study groups are out-

lined in Table 1. The percentage of secretor status among

patients with a tobacco-related habit and OSF (group I),

patients with a tobacco-related habit, but no lesions

(group II), and healthy controls (group III) is shown in

Figure 1. All of the patients in group I were non-secre-

tors, whereas in group II, 84.8% were non-secretors com-

pared to 15.2% in group III. A statistically-significant

difference was observed between groups I and III. The

correlation of duration and intensity of habits with secre-

tor status could not be done due to the large difference

in secretor status among the individuals in group II (cor-

relation requires at least equal distribution of secretor sta-

tus among the study group). Details of the association

between study groups and blood-group type is shown in

Table 2. It was also observed that OSF was more preva-

lent among those with blood-group A (36.36%) com-

pared to groups O (33.33%), B (27.27%), and AB

(3.03%).

Table 1. Type of tobacco-related habit and distribution percentage

among the study groups

Habits OSMF group % Habit group % Total

Areca nut 4 12.12 5 15.15 9

Gutkha 20 60.61 6 18.18 26

Pan masala 2 6.06 3 9.09 5

Combination 7 21.21 19 57.58 26

Total 33 100 33 100 66

OSMF, oral submucous fibrosis.

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Salivary secretory status K. Hallikeri et al.

Discussion

The prevalence rate of OSF in India ranges from 0.2% to

1.2%. Individuals between 20 and 40 years of age are

most commonly affected, but individuals aged between 2

and 89 years have also been reported to be affected.2 In

the present study, OSF was more prevalent in the second

decade of life, and was found to be strongly associ-

ated with a gutkha habit (20/33) of 1–10 years. Gutkha

chewing is a popular habit, with potential links to the

occurrence of oral cancer.15 Other tobacco-related habits

included betel nut chewing (4/33), pan masala (2/33),

and mixed habits (7/33).

The components of gutkha, such as areca nut extract,

are known to induce mutagenic and genotoxic effects, in

addition to inducing preneoplastic, as well as neoplastic

lesions of the oral cavity. Reactive oxygen species pro-

duced during auto-oxidation of areca nut polyphenols are

crucial in the initiation and promotion of oral cancer.16

The development of disease in patients with tobacco-

related habits is unpredictable. Inherent or host risk fac-

tors are most likely responsible for the development of

OSF. A detailed analysis of these factors is required to

assess the cause of lesion development in individuals with

tobacco-related habits. Based on this, in the present study,

we determined the secretor status in the above-mentioned

groups.

A secretor is defined as a person who secretes their

blood-type antigens into body fluids, such as saliva in the

mouth and mucous in the digestive tract and respiratory

cavity. A non-secretor puts little or none of their blood

type into these same fluids.14 The blood-group antigens

are genetically regulated by A, B, and H levels and secre-

tor genes, and subsequently, blood-group antigens are

expressed on erythrocytes and oral epithelial cells. These

cell surface carbohydrates are involved in cell-to-cell and

cell-to-substrate interactions, and changes in cell surface

carbohydrates are reflected in cellular behavior.13 The

non-secretor status of a patient could influence the devel-

opment of systemic and oral manifestations.

The ability to secrete blood-group antigens plays an

important role in the natural resistance of organism to

infection. Increased susceptibility to microbial infection

and a higher occurrence of urinary tract infection have

been reported in non-secretor individuals.17–19 Clark

et al.18 reported that non-secretors of the ABO group

antigen have an increased risk of developing peptic ulcers,

increased susceptibility to microbial infection, and a

higher occurrence of urinary tract infections. The ability

to secrete blood-group antigens plays an important role

in the natural resistance of organisms to infection. In a

study of 100 cases of leukoplakia, most of the non-secre-

tors were in the diseased group. Oral candidiasis among

non-secretors is also frequently. The non-secretor status

facilitates the prolonged candidal adhesion to mucosal

sites.20

In the present study, all the individuals in group I were

non-secretors; 84.8% of the individuals in groups II were

non-secretors and 15.2% were secretors. In contrast,

84.8% of the individuals in group III were secretors, and

only 15.2% were non-secretors.

We hypothesize that non-secretors might have an

added effect in the pathogenesis OSF, as all of the OSF

patients were non-secretors, and non-secretor individuals

with a tobacco-related habit are more likely to be prone

Table 2. Blood groups among the study groups

Blood OSMF group % Habit group % Control group % Total %

A 12 36.36 14 42.42 17 51.52 27 27.27

B 9 27.27 8 24.24 10 30.30 43 43.43

AB 1 3.03 2 6.06 4 12.12 7 7.07

O 11 33.33 9 27.27 2 6.06 22 22.22

Total 33 100.0 33 100 33 100 99 100.00

OSMF, oral submucous fibrosis.

Figure 1. Secretor status among the study groups. Group I, patients

with a tobacco-related habit and oral submucous fibrosis; group II,

patients with a tobacco-related habit, but no lesions; and group II,

healthy controls. ( ) Non Secretor; ( ) Secretor.

ª 2014 Wiley Publishing Asia Pty Ltd 3

K. Hallikeri et al. Salivary secretory status

to developing oral lesions. These patients would require

regular follow up to diagnose the disease as early as possi-

ble to provide the best treatment. To the best of our

knowledge, there have been no published studies compar-

ing secretor status in individuals with tobacco-related

habits; thus, ours is the first to estimate secretor status in

these individuals. Previous studies have correlated secretor

status and the severity of the disease, as in leukoplakia.21

Secretor status is well documented in oral cancer and pre-

malignant lesions, such as like leukoplakia, and fungal

infections, such as candidiasis.11,22 Vidas et al.14 studied

the secretor status in patients with pathological changes

of the oral mucosa in lichen ruber planus, erosivos, and

leukoplakia. Of the 61 patients, only 15 subjects were

non-secretors. The patients with a non-secretor status had

severe degree of the disease, whereas a mild degree of the

disease was recorded for the secretors. Secretor status has

been linked to the potentially-malignant oral lesions of

candidal leukoplakia; the non-secretor status facilitates

the prolonged adhesion of Candida to the mucosa, and in

addition, epithelial dysplastic changes seen exclusively in

non-secretors.23 The prevalence of Candida in OSF has

been reported to range from 40% to 63.6%, with Candida

albicans the predominant species isolated. These carry sig-

nificant risks of malignant transformation. The non-secre-

tor saliva not only fails to prevent attachment of Candida,

but also promotes the binding of Candida to tissue. With

potentially-malignant disease, the superadded candidal

infection needs special attention, as it is postulated that

nitrosamine compounds produced by Candida species

might directly, or together with other chemical carcino-

gens, activate specific proto-oncogenes, and thus facilitate

the development of malignant lesion.24–26 Cervoic et al.

studied the presence of the ABO antigen in the saliva of

patients with oral cancer, and found that 12 of 57

patients were non-secretors of blood-group antigens in

saliva. There was no significant difference between the

experimental and control groups.23

The interesting molecular basis is that epithelial cells in

non-secretors do not have an active flucosyl-transferase,

the activity of which is associated with the expression of

the ABO blood-group oligosaccharides. Human carci-

noma colon cell line has shown the loss of AB glycosyl-

transferse, which can enhance the malignancy of the cell

lines. Molecular studies of bladder cancer have shown

that the loss of expression of A-transferase is related to

the loss of chromosome at 9q34, which is a locus for the

ABO gene.27

The distribution of ABO blood groups in and around

Bangalore has been reported to be 9.81% for the O

group, 29.95% for the B group, 23.85% for the A group,

and 6.37% for the AB group.28 The South Indian study

by Das et al.29 showed that group O is the most predom-

inant, followed by groups B and A. Another South

Indian study, conducted in the Chittoor district of And-

hra Pradesh, India, also showed a similar pattern of

blood-group distribution.30 In the present study, it was

also observed that OSF was prevalent in patients with

blood-group A (36.36%), followed by groups O

(33.33%), B (27.27%), and AB (3.03%); however, these

correlations were not statistically significant. There are no

data available regarding the blood group and incidence

of OSF occurrence in these individuals. The present study

is a pilot study and the first of its kind to correlate secre-

tor status in individuals with OSF. However, future stud-

ies with larger sample sizes are required to confirm the

present findings.

The deletion of blood-group antigen A from premalig-

nant oral mucosal lesions is regarded as an example of

impaired synthesis of cell surface carbohydrates associated

with malignant change. This is due to the accumulation

of precursors or carbohydrates, that is, a H antigen in

premalignant lesions. The loss of the A antigen with the

accumulation of the H antigen suggests that the activity

of enzymes, which converts the H antigen to A, decreases

in premalignant lesions. In an immunohistochemistry

study, it was revealed that the H antigen accumulates in

the cell membrane of premalignant lesions with dysplasia,

and is irregularly distributed in oral squamous cell carci-

noma. This difference in distribution can be beneficial for

the early detection of cancer.21,31 Bryne et al.32 reported

that the loss of H-antigen expression at the invasive front

was well correlated with tumor development and the his-

tologic grade of tumor malignancy, rather than H-antigen

staining in the entire tumor.

In a prospective study by Lamey et al.,33 which

included 100 Sri Lankan patients with oral cancer and

controls, secretor status appeared to be an associated risk

marker for the development of lesions. In a hospital-

based study by Jaleel et al., blood groups were recorded

in oral cancer patients. It was concluded that people

with blood-group A were 1.46 times at a greater risk of

developing oral carcinoma, followed by those with

blood-groups B, AB, and O.12 There are various studies

reporting that individuals with blood-group A are prone

to developing carcinomas. In their studies, Raghavan

et al. and Toto and Nadimi34,35 also reported the

increased susceptibility of blood-group A to oral cancer.

Conclusion

Non-secretor status in an individual with a tobacco-

related habit indicates that there is alteration in the epi-

thelial surface carbohydrates, which marks the changes

in the epithelium and makes oral mucosa prone to dis-

ease development. The present study demonstrated that

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Salivary secretory status K. Hallikeri et al.

non-secretor individuals with a tobacco-related habit

developed oral lesions, thus patients with a history of

betel quid or areca nut habits in any form can be con-

sidered to be at risk. Secretor status can be part of rou-

tine investigations to assess the disease status and

whether an individual’s susceptibility manifests the dis-

ease. There is a need to analyze which particular groups

of individuals are more prone to develop OSF using

larger sample sizes.

Acknowledgments

The authors would like to thank Mrs Ambika Patil (Sri

Dharamasthala Manjunatheshwara College of Dental Sci-

ences & Hospital, Dharwad. Karnataka, India) for her assis-

tance in examining the salivary secretary status, and Dr

Arvind M. Yeri (Sri Dharamasthala Manjunatheshwara Col-

lege of Dental Sciences & Hospital, Dharwad. Karnataka,

India) for permitting us to utilize the laboratory facilities.

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