|Year : 2018 | Volume
| Issue : 4 | Page : 246-251
Review of 109 cases of primary malignant orofacial lesions seen at a Nigerian Tertiary Hospital
Olufunlola Motunrayo Adesina1, Olujide Oladele Soyele1, Elijah Olufemi Oyetola2, Olawunmi Adedoyin Fatusi1
1 Department of Oral and Maxillofacial Surgery/Oral Pathology, Obafemi Awolowo University, Ile-Ife, Nigeria
2 Department of Preventive and Community Dentistry, Obafemi Awolowo University, Ile-Ife, Nigeria
|Date of Web Publication||21-Dec-2018|
Dr. Olufunlola Motunrayo Adesina
Department of Oral and Maxillofacial Surgery/Oral Pathology, Obafemi Awolowo University, Ile-Ife
Source of Support: None, Conflict of Interest: None
Background: Orofacial malignancy is a growing health issue common in developing regions of the world. Presentation patterns are myriad with geographic variations. Advanced stage owing to late presentation constitutes a significant public health burden. The site and type of the lesions are valuable in diagnosis and patient management. Aim: This study aims to review cases of primary orofacial malignancies at the OAUTHC Dental Hospital. Objectives: The objective of the study was to determine the prevalence of histologically diagnosed orofacial malignancies, the relative frequencies, types and site of distribution. Materials and Methods: Records of patients with orofacial malignancies at the OAUTHC, Dental Hospital over a period of 10 years (January 2008–December 2017) were reviewed, demographic data (age, gender and site), history of tobacco use were retrieved and entered into a pro forma. The data obtained were analysed with STATA 11. Statistical significance was set at P < 0.05. Results: Of 375, 109 cases of neoplasms seen were primary malignant tumours, with prevalence rate of 29.1%. There were 71 (65.1%) males and 38 (34.9%) females (male:female ratio of 1.87:1), mean age (48.7 ± 19.3 years) and range (4–94 years). Affected sites were mandible (41, 37.6%), maxilla (39, 35.8%), palate (17, 15.6%) and others. Lesions were mainly squamous cell carcinomas (SCC: 46, 42.2%), salivary gland adenocarcinomas (SGAs, 25, 22.9%) including 8 (32%) cases of adenoid cystic carcinoma (ACC). Others were odontogenic carcinoma (18, 16.5%) and lymphoma (8, 7.3%). Most specimen analysed were hard tissues (n = 63, 57.8%). Thirty-four (73.9%) cases of SCC and 66 (60.6%) cases of primary malignancies were in the 5th–9th decades of life. This was statistically significant at P = 0.000. Conclusion: SCC was more prevalent than salivary and odontogenic carcinomas. ACC and mucoepidermoid carcinoma were two most common SGAs. Metastatic tumours to the jaws are rare.
Keywords: Adenoid cystic carcinoma, lymphoma, mucoepidermoid carcinoma, orofacial malignancies, squamous cell carcinoma
|How to cite this article:|
Adesina OM, Soyele OO, Oyetola EO, Fatusi OA. Review of 109 cases of primary malignant orofacial lesions seen at a Nigerian Tertiary Hospital. Niger Postgrad Med J 2018;25:246-51
|How to cite this URL:|
Adesina OM, Soyele OO, Oyetola EO, Fatusi OA. Review of 109 cases of primary malignant orofacial lesions seen at a Nigerian Tertiary Hospital. Niger Postgrad Med J [serial online] 2018 [cited 2020 May 30];25:246-51. Available from: http://www.npmj.org/text.asp?2018/25/4/246/248207
| Introduction|| |
Oral cancer is a growing health problem which is common in several regions of the world. Orofacial malignancies are malignant neoplasms of the oral cavity and adjacent structures excluding facial skin cancers, tend to affect all age groups and is commoner in the 5th–7th decades. However, certain malignancies predominate in children. Approximately 90% of these cancers are reported to be squamous cell carcinoma (SCC) with a range of 40%–51% (Nigerian studies) while a high predilection towards sarcoma has been observed from South Africa, Nigeria, and Libya with an aggregate 10.6% prevalence of carcinomas.,
These tumours exhibit variable growth and degree of aggressiveness which primarily determine the histologic grade.
Presentation patterns are myriad including soft tissue and bony swellings with ulcerations as well-exhibiting geographic variations in prevalence due to cultural, social, occupational or climatic factors.
Late presentation of patients presents challenges associated with normal function which manifest as facial disfigurement, impairment of eating, speech, swallowing and breathing. The treatment and outcome of these lesions are usually determined by the extent of spread/stage of the disease at presentation. The prognosis of these lesions is therefore poor; constituting a significant public health burden. Available literatures cite differential site predilections for orofacial malignancies.,,,,, One hundred and nine consecutive cases of primary orofacial malignant lesions seen over a 10-year period (January 2008–December 2017) at the Dental Hospital Unit, Obafemi Awolowo University Teaching Hospital, Ile-Ife, Nigeria were therefore reviewed to explore the prevalence and presentation patterns (age, gender and site) of these lesions in our centre.
The study was performed according to the ethical guidelines for research involving human subjects and ethical clearance obtained from our Health Research Committee of the Institute of Public Health, OAU (HREC No: IPHOAU/12/899) on 4th June 2018.
| Materials and Methods|| |
The biopsy records of the Oral Pathology Unit of patients with orofacial malignancies seen at the Dental Hospital, OAUTHC, Ile-Ife over a 10-year period (January 2008– December 2017) were reviewed. The age, gender, histologic diagnosis, tissue of origin and site of these malignancies and use/non-use tobacco were entered into a pro forma and analysed with STATA 11. Statistical significance was set at P < 0.05.
Data were analysed using Stata 11 (StataCorp College Station, Texas, USA). Descriptive statistics were carried out for socio-demographic variables such as age and sex. Quantitative data were summarised using mean, standard deviation (SD) and were analysed using Chi-square statistics. Statistical significance was set at P < 0.05. The age was stratified into age groups as well as into two groups of under and over 40 years.
| Results|| |
The 109 patients had a mean age of 48.7 ± 19.3 years (range: 4-94 years). There were 38 females and 71 males with a male to female ratio of 1.86:1 [Table 1]. The mandible was involved in 41(36.9%) and maxilla in 39 (35.6%) cases [Figure 1].
Epithelial malignant neoplasms constituted 23.7% (89 of 375) of all the biopsies seen within the period. Mean age at presentation was 59.6 years and range 17–94 years for SCC; 37.7 ± 12.9, range 5–59 years for odontogenic carcinomas and 51.4 ± 15.2, range 18–72 years for salivary gland adenocarcinomas (SGAs). Majority (76.1%, n = 67) of patients were 40 years or above [Figure 1] and [Figure 2] [Table 1] with a peak age of incidence in the 5th and 6th decade (n = 50, 71.4%) as shown in [Table 2]. There were 57 males and 32 females (M:F = 1.78:1). SCC was the most common lesion (n = 46, 51.7%), others being SGA (n = 25, 28.1%) and odontogenic carcinoma (n = 18, 20.2%) as shown in [Figure 1]. Common sites of occurrence were mandible gingival/alveolus (31, 34.8%) and maxilla (34, 38.2%), palate (16, 17.9%) and others as shown in [Figure 3] and [Table 3].
Twelve out of 375 biopsies (3.2%) processed within the period were sarcomas with age range from 4 to 50 years (mean age 30.5 ± 17.4 years). The peak age of incidence was in the 3rd decade of life (33.3% of patients) and an M:F ratio of 5:1 and mandible to maxilla ratio of 2:1 [Table 4]. There were two cases each of osteogenic sarcoma and MFH with one case each of Ewing sarcoma, chondrosarcoma, fibrosarcoma and neurogenic sarcoma.
Eight lymphomas (1.8%) seen within the period consisted of 6 (77.8%) cases of Non-Hodgkin's lymphomas (NHL) and two cases of Hodgkin's lymphomas. Of the six NHLs was one case of BL while four of the five remaining NHLs which were diffuse small cell type. The mean age ± SD of patients was 29.1 ± 13.9 years (range 10–53 years) and peak age of incidence was in the third decade of life as shown in [Table 2]. M:F ratio was 3.5:1 with three-quarters of these patients <40 years. Lesions were predominant in the mandible (n = 6, 75%). All patients (109, 100%) did not use tobacco [Table 5].
| Discussion|| |
The most commonly reported orofacial malignancy is oral SCC constituting 70%–90% of all lesions studied.,,, However, SCC constituted 42.2% (46 of 109) of all the orofacial malignancies and 51.6% (n = 46 of 89) of all epithelial malignant tumours in the present series contrary to other reports.,, This variation can be partly explained in the prevalence of major risk factors due to geographical differences due to dietary and trace element deficiencies.
The absence of indulgence in predisposing factors such as tobacco consumption in any form, alcohol intake and chewing of areca nuts or beta quid in patients in this study may also inform the reduced prevalence. The low prevalence may be attributable to this study being hospital based rather than population based. There was very little information available in the records with regards to tobacco and alcohol consumption in the present study [Table 5]. Although these are strong risk factors implicated in the development of orofacial malignancies, Oji and Chukwuneke corroborate our findings. On the contrary, Gbotolorun et al. reported a positive history of tobacco use in their series.
It is possible that other factors such as immunosuppression especially at the higher extremes of age, genetic mutation and dietary deficiencies as well as smoked foods, very hot foods, viruses and industrial pollution, are possible predisposing factors, especially in our patients. However, higher extremes of age recorded fewer cases of malignancies this study; therefore, the possibility of an overriding genetic predisposition may be a reasonable factor.
The mean age of patients with orofacial malignancies in the present study was 48.7 ± 19.3 years (range of 4–94 years). The occurrence of these malignancies in relatively older patients as observed in this study (66.1% of patients were older than 40 years) corroborates the possibility of a major role of ‘wear and tear’ of regulatory genes in the development of the malignant process. Recently, increasing trends of oral cancer in young people is generating interest in several regions of the world as possible early indulgence in tobacco or alcohol consumption is thought to be a factor.
Although more malignancies were observed in patients older than 40 years, people younger than 40 had peak occurrences. This was statistically significant at P = 0.002. However, variations exist in the cutoff point defined for young people. In our series, 21.1% of SCC were below 40 years as corroborated by Ajayi et al., who reported 25% of SCC in subjects less than 40 years. This is however contrary to reports from Libya (15%), Brazil (8.7%) and India (17%).
The probability of developing SCC increases with age. This is especially pertinent to SCC patients with mean age of 59.7 ± 16.7 years who were older than those with sarcomas (mean age: 28.3 ± 13.6 years) and lymphomas (mean age: 28.8 ± 13.1 years), P = 0.002 as has been earlier reported.,,, Oral carcinoma is an age-related disease, and about 90%–95% of patients are reported to be over the age of 40 years., However, SCC is on the increase in younger populations as reported by Chen et al. (UK). This emerging trend was similarly observed, for example, in this study, a higher number of SCC was observed in patients younger than 40 years.
There was a preponderance of male patients diagnosed with SCC (64.4%) compared to females, giving a 1.81:1 M:F ratio. Similar findings were observed in studies conducted in Asia with reports of up to three times more prevalence of carcinomas amongst the male gender., A male preponderance in the ratio of 1.4–1.9:1 was observed in Africa,, with the exception of Northern Nigeria and South African Indian Women., As for mucoepidermoid carcinoma (MEC), a 5:1 M: F ratio compared to a 1:2 ratio seen in adenoid cystic carcinoma (ACC) was observed in this study contrary to a 1:1 and 1: 2 reported by Bassey et al. and Otoh et al.
The overall male predominance worldwide is partially attributed to the limited mobility of females in this part of the world. This may also be due to the fact that more males indulge in the chief predisposing and/or traditional factors of tobacco use and alcohol consumption. However, the current research findings show an increasing trend of indulgence in these twin factors by women. It is possible that other factors such as genetic predisposition and diet deficient in antioxidative vitamins and trace elements may explain this male preponderance.,
The relative frequency of tumours at different sites varies widely in reports from different countries as Smith showed by tabulations among different populations. There was a predilection for the mandible in this study (n = 41, 37.6%) and maxilla [Figure 3] as alluded to by Ajayi et al. but contrary to reports of Gbotolorun et al. and Daramola et al. who both found the tongue as the most prevalent site in their respective studies. However, the tongue was the least commonly reported site in this study (n = 2, 2.4%). The occurrence in the jawbones is often thought to be secondary to invasion from the adjoining gingival and floor of the mouth; which are usually the primary sites of SCC in the oral cavity.
As the lip was involved in only three cases (2.8% of orofacial malignancies and 6.7% of SCC [Figure 3]; corroborating its rarity in this part of the world. It strengthens the earlier observation that lip cancer is rare among the black population as the dark pigmented lip of Blacks is believed to confer some protection from the carcinogenic effect of actinic radiation. This agrees with low values 2.6%–3.6% reported from previous Nigerian and Zimbabwean studies.,,,
The palate was the most common intraoral site (17, 15.6%) followed by the cheek in agreement with Lawoyin et al. and Nwashidi and Otasowie. Unlike India where reverse smoking has been implicated, the extent of this practice has not been investigated in Nigeria. Ugboko et al. and Odukoya et al. found the alveolus and gingivae as the predominant intraoral sites, respectively. This site predilection by Ugboko et al. may be due to the multicentric nature of their study and positive history of indulgence in twin risk factors of tobacco use and alcohol.
People have documented dependent areas such as the tongue and floor of the mouth which are rare in this study. Carcinogens in either tobacco or alcohol or dietary substances dissolved in saliva tend to pool and accumulate in gravity-dependent areas of the mouth., The rarity of SCC in the tongue and complete absence in the floor of the mouth in this study is at variance with the finding.
An analysis of the histological profile of SCC revealed a near equal predomination of moderately differentiated, and well-differentiated i.e., 15–14 cases as observed in Port Harcourt and Ibadan but is incongruent with the findings from Chen et al.; who attributes this to the subjective nature of histopathologic characterisation.
Carcinoma arising from salivary glands (n = 25, 28.4%) were the second most common in the present study in agreement with the observation made by Ajayi et al., and occurred within minor salivary glands (76%, n = 19) in agreement with several studies which reported a higher incidence of malignancy in minor salivary glands.,,, ACC accounting for 28% cases (n = 7) was slightly predominant in agreement with the study from Lagos. This is incongruent with reports that found MEC as the most common malignant salivary gland tumour. Malignancies of the major gland were expectedly low in this series can be explained by the involvement of different surgical subspecialties in the management of major salivary gland tumours in our centre. The study did not included salivary gland tumours that presented to other specialties such as ENT and General Surgery.
There were 12 (11%) cases of sarcomas of which 67% of subjects were below 40 years with a predilection for mandible and seen in ages. This is in concordance with Ogunlewe et al. who reported that sarcomas affected a considerably younger age group than carcinomas.
Lymphomas are malignant lesions that can arise from any type of lymphocyte, but most frequently from B-cells. Lymphomas constituted 2.4% of orofacial malignancies in the present study and were the B-cell type. Previous reports from Africa, and the Middle-east reported a higher range (4%–19%). In our study, more than half of the lymphomas were located in the mandible contrary to the reports of Ajayi et al and Akinmoladun et al., Diffuse small cell type was the predominant histologic variant (75%) of NHL (66.7%) The only case of BL was observed in a 10-year-old male. Ajayi et al., and Chidzonga reported a higher incidence of BL--5% with male preponderance and occurrence in the first decade of life. While their findings represent the endemic presentation observed in Nigeria, the rarity in our series may be due to the fact that cases of BL are usually managed by haematologists in our centre. While Hodgkin's lymphoma is primarily a disease of lymph nodes and is seldom found in the oral cavity, the two cases observed in this series were of the lymphocyte predominant type.
MFH and melanoma were the rare lesions in this study. Available literature suggests that MFH commonly involves soft-tissues in adults, and bony tissues at any age. The rarity of involvement of orofacial sites, was corroborated by the observance of only two cases in this study.
The single case of malignant melanoma observed in the maxillary gingiva was seen in an elderly man. The rarity of this lesion was confirmed by Chidzonga who reported of 8 (2%) cases of malignant melanoma out of a cohort 428 oral malignant tumours.
| Conclusion|| |
SCC was more prevalent than salivary and odontogenic carcinomas and was observed in 5th–8th decade. ACC and MEC were two most common salivary gland malignancies. While odontogenic carcinomas were common in the mandible, SCC and SGAs were predominant in the maxilla and palate. None of the cases in this study alluded to the use of tobacco.
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[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]