RESUMO
OBJECTIVES: Ameloblastoma is a benign but highly infiltrative tumour, a behaviour that is lacking in adenomatoid odontogenic tumour but partly shared by the odontogenic keratocyst which possesses a unique intrinsic growth potential with marked ability for destroying bone and a high tendency recurrence. High frequency of stromal myofibroblasts (assessed with alpha smooth muscle actin (α-SMA) correlates with aggressive behaviour while p53-cell cycle regulation system is critical in odontogenic tumours with immunoreactivity signifying prognostic status. This study aims to determine and compare the immunoreactivity of these selected tumours to p53 and α-SMA in order to establish if a relationship exists between the frequency and pattern of distribution of myofibroblasts and the behaviour of these lesions. MATERIALS AND METHODS: 69 blocks of ameloblastoma, and 23 each of adenomatoid odontogenic tumor (AOT), and odontogenic keratocyst (OKC/KCOT) were retrieved. Immunohistochemistry technique was applied for evaluation of these two markers staining with primary antibodies to p53 and ï¡-SMA and the frequency and pattern of distribution of myofibroblasts and immunoreactivity to p53 analysed and compared using ANOVA. p was set at <0.05. RESULTS AND CONCLUSION: Immunoreactivity to p53 and α-SMA was highest in ameloblastoma (solid compared to unicystic) with highest mean positive cells to α-SMA (29.7±20.1) and p53 (28.3±24.5) in plexiform ameloblastoma. This suggests that ameloblastoma was the most aggressive of tumours studied. Different pharmacological agents that can regulate stromal MF are useful aids to decrease the need for radical surgery in extensive and aggressive odontogenic tumours.
ABSTRAIT OBJECTIFS: L'améloblastome est bénin mais untumeur mes infiltratif, un comportement qui fait défaut dans la tumeur odontogénique adénomatoïde mais en partie partagé par le kératocyste odontogène qui possède un potentiel de croissance intrinsèque unique avec une capacité marquée de destructionet une récidive à forte tendance. Haute fréquence de stromalmyofibroblastes (évalués avec de l'actine musculaire alpha lisse (α-SMA) est en corrélation avec un comportement agressif lors de la régulation du cycle des cellules p53 est essentiel dans les tumeurs odontogènes immunoréactives signifiant le statut pronostique. Cette étude vise à déterminer et comparer activité l'immunoré de ces tumeurs sélectionnées à p53 et α-SMA afin d'établir s'il existe une relation entre le fréquence et schéma de distribution des myofibroblastes et de la comportement de ces lésions. MATÉRIAUX ET MÉTHODES: 69 blocs d'améloblastome, et 23 chacun de tumeur odontogénique adénomatoïde (AOT) et odontogènedes kératocystes (OKC/KCOT) ont été récupérés. Immunohistochimiela technique a été appliquée pour l'évaluation de ces deux marqueurs de coloration avec des anticorps primaires dirigés contre p53 et α-SMA et la fréquence et schéma de distribution des myofibroblastes et de l'immunoréactivité àp53 analysé et comparé à l'aide de l'ANOVA. p a été fixé à <0,05. RÉSULTATS ET CONCLUSION: Immuno réactivité à p53 et α-SMA était la plus élevée dans l'améloblastome (solide par rapport α-SMA (29,7±20,1) et p53(28,3±24,5) dans l'améloblastome plexiforme. Cela suggère que L'améloblastome était la tumeur la plus agressive étudiée. Les agents pharmacologiques différentes peuvent réguler la MF stromale sont des aides utiles pour diminuer le besoin de chirurgie radicale en cas de chirurgie étendue et agressive tumeurs odontogènes. Mots-clés: Améloblastome, AOT, OKC/KCOT, p53, α-SMA, myofibroblastes, tumeurs odontogènes, immunoréactivité.
Assuntos
Ameloblastoma , Cistos Odontogênicos , Tumores Odontogênicos , Ameloblastoma/patologia , Humanos , Cistos Odontogênicos/patologia , Tumores Odontogênicos/patologia , Proteína Supressora de Tumor p53/análiseRESUMO
BACKGROUND: Oral mucosal melanoma (OMM) is a malignant lesion of melanocytes of oral epithelium. The prevalence in four Nigerian teaching hospitals is reported. AIMS: This study shows the hospital based prevalence and the clinicopathologic features of OMM in four Nigerian teaching hospitals. SUBJECTS AND METHODS: A retrospective study of patients diagnosed with OMM in four teaching hospitals in Nigeria was carried out. All records of patients with orofacial lesions from 1969 to 2016 were identified and retrieved from the archives of four oral pathology departments. The biodata and relevant clinicopathologic information of those diagnosed with OMM were reviewed. Data analysis was done with SPSS for Windows, version 20. RESULTS: There were 10,877 orofacial lesions managed during the period. Oral malignant lesions constituted 14.4% (1,552/10,877). OMM was diagnosed in ten patients with prevalences of 0.09% and 0.6% of all orofacial lesions and oral malignancies, respectively. There was a male predilection of 4:1 and a mean age of occurrence of 53.8 (±12.6) years. The palate was the most frequent site, 40.0% (4/10). Regional lymph nodes were hard, fixed, or matted in 50.0% (5/10) of patients and distant metastases observed in 20.0% (2/10). Among those followed up, only one was documented alive after 6 months. Amelanotic OMM, 20.0% (2/10) did not show ulceration or regional and distant metastasis. CONCLUSIONS: OMM has a low prevalence but with poor prognosis. Amelanotic OMM showed less clinical aggression. Early diagnosis and prompt treatment are recommended.
Assuntos
Melanoma/patologia , Mucosa Bucal/patologia , Neoplasias Bucais/patologia , Adulto , Idoso , Feminino , Hospitais de Ensino , Humanos , Linfonodos , Masculino , Melanoma/epidemiologia , Melanoma/cirurgia , Pessoa de Meia-Idade , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/cirurgia , Nigéria/epidemiologia , Palato , Prevalência , Estudos Retrospectivos , Adulto JovemRESUMO
BACKGROUND: The objective of this study was to classify the various types of odontogenic tumours (OTs) using the newly updated 2017 world health organization (WHO) histological typing and to analyze the prevalence of these tumours among Nigerians as well as to compare the results obtained with reports from world-wide studies. MATERIAL AND METHODS: The records of four major tertiary hospitals in Nigeria were reviewed over a 12-year (2004-2015) period. Lesions diagnosed as odontogenic tumours were classified into four groups according to the 2017 WHO histological typing. Data which consisted of age, sex and site were analyzed using SPSS for Window (version 20.0; SPSS Inc., Chicago, IL) and frequency tables were computed. RESULTS: A total of 582 OTs were recorded and reviewed, benign OTs were 573 (98.5%) cases and malignant OTs were 9 (1.5%) cases. Of the benign OTs, the epithelial OTs were the commonest (500; 86%) while the benign mixed OTs were the least frequent (21; 3.6%). The mean age was 30±14 years (age range of 3-77years) and the peak age was in the third decade (197; 33.8%) of life. There was slight male gender and strong mandibular site predilection. Ameloblastoma, was the most frequent OT and it accounted for 75.5% of the OTs, followed by adenomatoid odontogenic tumour (8.1%) and odontogenic myxoma (7.2%). Malignant OTs accounted for 1.5% of the OTs. CONCLUSIONS: OTs show a geographic variation with tendency for prevalence of the epithelial OTs in Africa. Ameloblastoma has a high prevalence among Nigerians and is the most common OTs in Africa. Prevalence of odontoma is relatively low in developing African countries like Nigeria when compared to the prevalence in developed countries.
Assuntos
Tumores Odontogênicos/classificação , Tumores Odontogênicos/epidemiologia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nigéria/epidemiologia , Tumores Odontogênicos/patologia , Prevalência , Estudos Retrospectivos , Adulto JovemRESUMO
Ameloblastoma is a benign odontogenic tumor of epithelial origin. It is locally aggressive with unlimited growth capacity and has a high potential for malignant transformation as well as metastasis. Ameloblastoma has no established preventive measures although majority of patients are between ages 30 and 60 years. Molecular and genetic factors that promote oncogenic transformation of odontogenic epithelium to ameloblastoma are strongly linked to dysregulation of multiple genes associated with mitogen-activated protein kinase, sonic hedgehog, and WNT/ß-catenin signaling pathways. Treatment of ameloblastoma is focused on surgical resection with a wide margin of normal tissue because of its high propensity for locoregional invasion; but this is often associated with significant patient morbidity. The relatively high recurrence rate of ameloblastoma is influenced by the type of molecular etiological factors, the management approach, and how early the patient presents for treatment. It is expected that further elucidation of molecular factors that orchestrate pathogenesis and recurrence of ameloblastoma will lead to new diagnostic markers and targeted drug therapies for ameloblastoma.
Assuntos
Ameloblastoma , Neoplasias Maxilomandibulares , Ameloblastoma/diagnóstico por imagem , Ameloblastoma/etiologia , Ameloblastoma/patologia , Ameloblastoma/terapia , Humanos , Neoplasias Maxilomandibulares/diagnóstico por imagem , Neoplasias Maxilomandibulares/etiologia , Neoplasias Maxilomandibulares/patologia , Neoplasias Maxilomandibulares/terapia , Recidiva Local de NeoplasiaRESUMO
Oro-facial malignancies are reported to have a high mortality and morbidity, this is further worsened when patient report late. To analyze the malignant oro-facial lesions seen at a Hospital in the Lagos, Nigeria. Successive patients that presented in the hospital and met criteria of study during 15 months period were recruited into the study. Demographics, clinical variables, and treatment provided for each patient in the hospital was recorded. Data collected were presented as tables and percentages. There were 36 cases seen, their ages ranged from 10 to 72 years (median 49 years), and there were 21 males and 15 females. Time lapse before presentation to the clinic ranged from 2 to 30 months, mean (9.9 (±5.5 months and the largest dimension of lesions at presentation ranged from 2 cm to 12 cm (mean 6.4 ± 2.0 cm). Most common site of presentation was posterior tongue (16.7%; 6/36) and Squamous cell carcinoma (41.6%; 15/36) was the most common histopathologic diagnosis. Twenty-three patients (63.9%; 23/36) had primary surgeries in the hospital. Patients seen in this case series generally reported late with large lesions.
RESUMO
BACKGROUND: Unfortunately, despite an increase in medical knowledge, survival rates of head and neck cancers (HNCs) have not been observed to improve greatly. This is true, especially in tumors located in obscure primary sites or late presentation. AIM: The purpose of this study is to assess the epidemiologic pattern of HNCs and to evaluate its emerging trends and patterns in Lagos state. SUBJECTS AND METHODS: A retrospective study was conducted from 2003 to 2013 that analyzed histologically diagnosed cases of HNC at the Pathology Departments of the two tertiary teaching hospitals in Lagos. Data analysis was performed using the Statistical Package for the Social Sciences (version 20) statistical software. RESULTS: One thousand and eighty-three cases of head and neck malignancies were recorded. A female: male ratio of 1.01:1 was reported with mean age of 39.6 (standard deviation 21.1) years. The oral cavity was the most affected anatomic site (21.2%, 230/1083) in the period under review. Malignant epithelial tumors accounted for 72% (779/1083) of cases seen. Carcinomas were the most common histological variant seen (67%, 726/1083) and squamous cell carcinoma accounted for 58% (421/726) of carcinomas recorded. Oral cavity malignancies (21.8%, 118/540) were the most common in males while thyroid malignancies (28.5%, 155/543) were the most seen in females. In children (≤15 years), the most common histologic findings were carcinomas (42.3%; 77/182) and retinoblastomas (23.6%; 43/182). CONCLUSION: Epithelial malignancies were the most common malignancy in the study, and the oral cavity appears to be the increasingly predominant site for HNCs. A changing pattern in gender predominance, age distribution, and frequency with histological variants and anatomical sites was also observed in this study.
RESUMO
BACKGROUND: Malignant fibrous histiocytoma (MFH), is a soft tissue sarcoma that occurs predominantly in the soft tissue of the extremities. It rarely occurs in facial bones. Few cases in the jaws have been reported. OBJECTIVE: To report and review the relevant clinicopathologic features of 5 cases of jaw MFHin Nigerians. METHODS: All cases in the records of the Department of Oral Pathology of the Lagos University Teaching Hospital which were histologically diagnosed as MFH were retrieved. Hematoxylin and eosin slides of cases were re-examined to confirm diagnosis. Information retrieved included age, sex, location, x-ray, estimated duration, recurrence, and histological presentation. Data was analyzed using SPSS statistical package. RESULTS: Age ranged between 12-42 years with a male sex predilection (3 cases/60.0%) and sole maxillary site predilection (5 cases/100.0%). Estimated duration of lesion ranged from 2 -12 months. Two cases recurred post surgical treatment. All cases presented as the storiform-pleomorphic type with one case presenting with a delicate/scanty connective tissue stroma. Chronic inflammation was scanty in the two cases that recurred. CONCLUSION: MFH of the jaws is rare among Nigerians. Its clinico radiological presentation maymimick other more aggressive or less benign lesions of the jaws thereby resulting in misdiagnosis and in appropriate patient management.
Assuntos
Histiocitoma Fibroso Maligno/patologia , Neoplasias Maxilomandibulares/patologia , Adolescente , Adulto , Criança , Feminino , Histiocitoma Fibroso Maligno/epidemiologia , Humanos , Neoplasias Maxilomandibulares/epidemiologia , Masculino , Nigéria/epidemiologia , Fatores Sexuais , Fatores de TempoRESUMO
BACKGROUND: The aim of this study was to review the clinicopathologic features of focal reactive gingival lesions at the Lagos University Teaching Hospital, Nigeria. METHODS: A retrospective review of cases of different focal reactive gingival lesions from the records of the Departments of the Oral Biology/Oral Pathology and Oral and Maxillofacial Surgery of the Lagos University Teaching Hospital between 1970 and 2008 was carried out. Available clinical data regarding age, gender, location, estimated duration of the lesion and treatment modality were obtained and analyzed. RESULTS: Prevalence rate of focal reactive gingival lesions was 5.6%. Pyogenic granuloma (PG) was the most common lesions constituting 57% of the cases. Seventeen (9.5%) of the 179 cases of PG were pregnancy induced pyogenic granuloma. The female-to-male ratio was 1.7:1. All the 4 lesions occurred more in female patients than males. The mean age of patients at presentation was 30 ± 16.5 years. The lesions were commonly seen in the second and third decade of life and least commonly seen above the age of 60 years. The lesions were equally distributed on the maxillary and mandibular gingivae, and were mostly located on the buccal gingival of the jaws. Most (51.6%) of the lesions occurred in incisors/canine region. Recurrence of the lesions was seen in 9 cases (2.9%), all pyogenic granuloma. CONCLUSION: Focal reactive gingival lesions are relatively uncommon lesions of the oral cavity with a prevalence rate of 5.6%. The lesions occurred commonly in females, and in third decades of life. Pyogenic granuloma was the most common lesions constituting 57% of all cases.
RESUMO
BACKGROUND & OBJECTIVES: The study was aimed at elucidating the prevalence and intensity of Mansonella perstans microfilaraemia in the Emohua Local Government Area, Nigeria, and ascertaining the abundance, circadian, and the annual biting patterns of the Culicoides vector. METHODS: Thick smear of 50 µl finger-prick blood stained with Giemsa was examined microscopically in a cross-sectional study. Vector landing collection on human bait was employed in a longitudinal study of the vector biting patterns, carried out between July 2005 and August 2006. RESULTS: Of 1486 individuals examined, 11.2% of both males and females were positive for M. perstans microfilaraemia. Microfilaraemia appeared early in life. The overall geometric mean intensity among those with positive microfilaraemia was 117 mf/ml (121 mf/ml for males and 113 mf/ml for females). The differences in geometric mean intensity between different age groups were statistically significant (one-way analysis of variance; p <0.05), being highest in the oldest age group (266 mf/ml). A total of 1183 female Culicoides sp were caught from September 2005 to August 2006. The abundance of Culicoides sp was seasonal. The circadian biting activity had a broad peak between 0700 and 1200 hrs. The monthly biting rates ranged from zero bite per person per month in January 2006 to 1151 bites per person per month in June 2006. The annual biting rate was 7382 bites per person per year. CONCLUSION: Majority of those with positive microfilaraemia were poor socioeconomically, underscoring the need for health education and application of effective control measures against Culicoides biting midges in Emohua.
Assuntos
Ceratopogonidae/fisiologia , Doenças Endêmicas/estatística & dados numéricos , Mordeduras e Picadas de Insetos/epidemiologia , Mansonella/isolamento & purificação , Mansonelose/epidemiologia , Parasitemia/epidemiologia , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Mordeduras e Picadas de Insetos/parasitologia , Insetos Vetores/fisiologia , Governo Local , Estudos Longitudinais , Masculino , Mansonella/fisiologia , Mansonelose/parasitologia , Pessoa de Meia-Idade , Nigéria/epidemiologia , Parasitemia/parasitologia , Prevalência , Estações do Ano , Adulto JovemRESUMO
BACKGROUND: Odontogenic myxoma (OM) is a locally aggressive neoplasm whose clinicopathological characteristics have not been extensively reported in Nigerians. OBJECTIVE: To describe the clinicopathological characteristics of cases of OM seen at the Lagos University Teaching Hospital in Nigeria. METHODS: A review of both clinical and histopathological records of sixty-three cases of OM diagnosed over a period of thirty-seven years was undertaken. The cases were analyzed for age, sex, site, size, duration and histological contents of collagenization, odontogenic epithelium and calcification. RESULTS: Odontogenic myxoma represented 63(11.2%) cases of odontogenic tumours, was commonest in the second to forth decades and rare below age 10 and above 70 years. It was more common in females. Maxillary lesions were more common with respect to both central and peripheral histologic types, but occurred in equal frequencies in mandible and maxilla with respect to the central histologic type. Forty-seven (74.6%) cases were fibromyxoma and sixteen (25.4%) myxoma. Odontogenic epithelium was rare and observed in 5 (9.5%) cases while calcific material was present in sixteen (25.4%) cases. Late presentation was a common feature and surgical excision was the treatment of choice. CONCLUSION: Odontogenic myxoma is un-common among Nigerians when compared with ameloblastoma. Clinicopathological characteristics in this series are similar to information in the scientific literature.
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Mixoma/diagnóstico , Tumores Odontogênicos/diagnóstico , Adolescente , Adulto , Distribuição por Idade , Idoso , Biópsia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Mixoma/epidemiologia , Nigéria/epidemiologia , Tumores Odontogênicos/epidemiologia , Adulto JovemRESUMO
SUMMARY: Clinicopathological analysis and growth rate study of 100 cases of ameloblastoma was undertaken. The tumour had site predilection for the mandible (91.0%) and occurred more in males than in females (ratio 1:0.9). 62.0% of patients in the series were less than 20 years of age. The estimated monthly growth rate (EMGR) of ameloblastoma was observed to be slower in males although the mean tumour volume recorded in females was lower than males in the series. The biologic aggression of 4 various types of ameloblastoma was predicted using EMGR and average volume of tumour at hospital presentation as predictive markers. Solid multicystic ameloblastoma was observed with the fastest EMGR of 0.81 cm(3)/month. Peripheral ameloblastoma was observed with the slowest EMGR of 0.17 cm(3)/ month. It was concluded that all the 4 types of ameloblastoma observed were clinically distinct and showed varying biologic aggression. The solid multicystic type with the highest growth rate (0.81 cm(3)/month) was considered the most aggressive while the peripheral type (growth rate = 0.17 cm(3)/month) was the least aggressive. It is therefore necessary to distinguish between the various clinical types of ameloblastoma before a clinician proceeds with definitive treatment.
Assuntos
Ameloblastoma/patologia , Neoplasias Maxilomandibulares/patologia , Adolescente , Adulto , Idoso , Ameloblastoma/epidemiologia , Feminino , Humanos , Neoplasias Maxilomandibulares/epidemiologia , Masculino , Pessoa de Meia-Idade , Nigéria/epidemiologiaRESUMO
PURPOSE: This is a retrospective study of the location, diagnosis, sex and age distribution and treatment of minor salivary glands tumours of the upper aero digestive tract in Lagos, Nigeria. MATERIAL AND METHODS: Case files and radiographs of patients treated over a 24-year period were reviewed. RESULTS: These tumours constituted 40.4% of all salivary gland tumours in the series. The majority (62.3%) of these tumours was malignant, and the most common malignant tumour was mucoepidermoid carcinoma (19.2%). However, pleomorphic adenoma (34.2%) was the most common tumour overall. Both benign (67.2%) and malignant (23.9%) tumors were most frequently located in the palate. Both sexes were equally affected (Male-female ratio 1 to 1), but a higher proportion of benign tumours were found in the palate of females (75%) than their male counterparts (64%). Patients with adenoid cystic carcinoma were significantly older at presentation than those with pleomorphic adenoma and adenocarcinoma (P < 0.05). CONCLUSION: These findings show that majority of these tumours were malignant (62.3%), though pleomorphic adenoma was the most common tumour. They also confirm the high predilection of pleomorphic adenoma (61.8%) for the palate of Black Africans.
Assuntos
Adenoma Pleomorfo/patologia , Carcinoma Mucoepidermoide/patologia , Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares Menores/patologia , Adolescente , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma Adenoide Cístico/patologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nigéria , Neoplasias Palatinas/patologia , Estudos Retrospectivos , Distribuição por Sexo , Adulto JovemRESUMO
A retrospective review of cases histologically diagnosed as malignant lesions of the orofacial region in 1992-2003 from the records of the Department of Oral Pathology and Biology, Lagos University Teaching Hospital, Nigeria was carried out. All cases were subjected to analysis of age, gender, site distribution and histologic types. Malignant tumours constituted 18% of all the biopsies of orofacial lesions seen within the period. The mean age of patients was 42.2+/-21.5 years (range: 2.5-85). There were 177 (69%) epithelial tumours of which squamous cell carcinoma was predominant, 47 (18%) sarcomas and 32 (13%) lymphomas. Squamous cell carcinoma (44%) was the most common malignant orofacial tumour. Osteosarcoma (32%) and Burkitt's lymphoma (56%) was the predominant sarcoma and lymphoma, respectively. Patients with a histologic diagnosis of carcinoma were older than those with sarcomas and lymphomas (P<0.01), and those with a histologic diagnosis of malignant lymphoma were significantly younger than those with sarcomas (P<0.01). Almost 25% of patients with carcinomas were below the age of 40 years. Malignant orofacial tumours are not uncommon in the studied environment, with a sizable proportion of carcinomas occurring before the age of 40 years.
Assuntos
Neoplasias Faciais/epidemiologia , Neoplasias Bucais/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Linfoma de Burkitt/epidemiologia , Carcinoma/epidemiologia , Carcinoma de Células Escamosas/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Linfoma/epidemiologia , Masculino , Neoplasias Mandibulares/epidemiologia , Neoplasias Maxilares/epidemiologia , Pessoa de Meia-Idade , Nigéria/epidemiologia , Osteossarcoma/epidemiologia , Estudos Retrospectivos , Sarcoma/epidemiologia , Fatores SexuaisRESUMO
AIM: Clinicopathological analysis and melanin pigmentation occurrence in adenomatoid odontogenic tumour (AOT) diagnosed and managed at the Lagos University Teaching Hospital during a 29- year period. METHODS: Records of 31 cases were reviewed and standard epidemiological data were obtained. Haematoxylin and eosin stained slides of the cases were retrieved and reevaluated for reconfirmation of diagnosis. Celloidinised paraffin sections of all cases were subjected to Fontana Masson stain and melanin bleach to assess presence of melanin pigment. RESULTS: AOT is an uncommon type of odontogenic tumour that is commoner in younger age group (8-35 years) with site predilection for the anterior maxilla (64.5%). Occurrence of melanin pigment in AOT was very rare as there was positive melanin pigmentation in only one case in spite of the fact that the study was carried out in a predominantly Black population. CONCLUSION: Pattern of occurrence of AOT observed in this Lagos series is similar to previous studies in the scientific literature. Melanin pigmentation is rarely demonstrated in AOT even in a predominantly Black population.