Clinico-pathological Pattern Of Odontogenic Neoplasms At Two National Referral Centres In Nairobi, Kenya

Abstract

Background: Odontogenic neoplasms (ONs) are lesions with insidious progress but tend to cause disfigurement and high surgical morbidity. The prevalence in Africa is about 9-69%. Knowledge of their trend and pattern of presentation both clinically and pathologically is of utmost importance. The paucity of data in Kenya necessitated the present study which entailed an audit of patients’ records over a period of 7 years extending from January 2012 to December 2018. It evaluated the clinical and pathological pattern of presentation of odontogenic neoplasms at the Kenyatta National Hospital (KNH) and the University of Nairobi Dental Hospital (UNDH) to demonstrate the current trends in the pattern of their presentation. Objective: The main objective was to retrospectively describe the clinical and pathological pattern of odontogenic neoplasms seen at the KNH and the UNDH between January 2012 and December 2018. Materials and methods: This was a descriptive retrospective research design. The study sample comprised of records of patients who presented and were diagnosed with jaw neoplasms at the KNH and the UNDH from 1st January 2012 to 31st December 2018. A specially designed data collection form was used to record relevant information to the study including age, gender, nationality, race, primary or recurrent neoplasm anatomical site, duration, symptoms and histological diagnosis. The data collected were analysed using statistical package for the social sciences (SPSS). Both descriptive and inferential statistics were used to interprete the data. Frequencies, percentages, means and standard deviations were used to describe the patterns of the investigated study variables. Inferential statistics included Chi-square and independent t-test. Chi-square was used to determine relationships between the participants’ demographic characteristics (age, gender, nationality, race, and home area) and primary neoplasm, recurrent neoplasm, anatomical site of the disease and duration of neoplasms. On the other hand, the independent t-test was used to determine whether there was a statistically significant difference between the gender and ages of patients with ONs during the study period. Results There were 372 cases of ONs that were diagnosed at the KNH and the UNDH. These comprised 47.6% of all jaw lesions at the two centres. The age range of the cases was 5.5-77 years with a mean of 30.165(SD±15.15.77). The peak age of occurrence of ONs was the 3rd decade of life. The male to female ratio was 1:1.1. Most of the cases (220, 60.8%) originated from rural areas. ONs were predominantly benign (369 cases, 99.2%), while the malignant ones were rare (3 cases, 0.8%). Primary ONs were 351 cases (94.4%) while recurrent ONs were 21 cases (5.6%). The mandible was the predominantly involved site (295 cases, 79.3%), with mandible to maxilla ratio having been 4:1. ONs in the maxilla commonly occurred in the anterior region. Swelling was the commonly reported symptoms in 360 cases. Other symptoms included tooth mobility, mal-aligned/displaced teeth, pain, secondary infection, unerupted teeth and rarely ulceration. Most cases presented between 1 to 5 years following the onset of symptoms. Ameloblastoma was the most common ON (242 cases, 65.1%). Other ONs seen in this study included cemento-ossifying fibroma (40 cases), odontogenic myxoma (35 cases), odontoma (27 cases), adenomatoid odontogenic tumour (17 cases), ameloblastic fibroma (4 cases), odontogenic fibroma (4 cases), clear cell odontogenic carcinoma (2 cases) and ameloblastic carcinoma (1 case). Ameloblastoma had the follicular type (51 cases) as the commonest histologic subtype. Other subtypes were the plexiform (44 cases), cystic (42 cases), granular (1 case) and mixed (35 cases). The odontoma had the complex subtype reported in only two cases. Conclusion ONs are common jaw lesions in patients aged below 40 years who presented at the KNH and the UNDH. The posterior mandible was the most involved site. In the maxilla, the anterior region was commonly involved. Ameloblastoma was the most common ON. Recommendations The creation and implementation of policies in the public health system that will impact on the diagnosis and management of ONs by bringing specialized medical services closer to the population such as in the rural areas. In addition, there should be sensitization of the citizenry on the occurrence of ONs, the long-term effect, and the need to seek early treatment (less than 1year since the onset of symptoms).