Ameloblastoma of the jaw and maxillary bone: clinical study and

AVANCES EN ODONTOESTOMATOLOGÍA/367

Di Cosola M, Turco M, Bizzoca G, Tavoulari K, Capodiferro S, Escudero-Castaño N, Lo Muzio L.Ameloblastoma of the jaw and maxillary bone: clinical study and report of our experience

SUMMARY

In order to ameloblastoma´s cases series, benign tumour of epithelial origin, we will value the histological andradiographic common findings, its frequent symptomatology, and we will estimate the prevalence variationaccording to the age, gender, lesion localization, etc.In the other hand, we will emphasize the principal risk factors and we will classify the different treatmentaccording to its histology, clinic and type of lesion.

Key words: Solid-multicystic ameloblastoma, unicystic ameloblastoma.

Receibed: Febrero 2007.Acepted for publication: Marzo 2007.

* Department of Dentistry and Surgery, University of Bari, Italy.** Departament of Oral Medicine and Bucofacial Surgery, Complutense University of Madrid, Spain.*** Department of Oral Pathology, University of Foggia, Italy.

Di Cosola M, Turco M, Bizzoca G, Tavoulari K, Capodiferro S, Escudero-Castaño N, Lo Muzio L. Ameloblasto-ma of the jaw and maxillary bone: clinical study and report of our experience. Av. Odontoestomatol 2007; 23(6): 367-373.

Ameloblastoma of the jaw and maxillarybone: clinical study and report of ourexperience

Di Cosola M*, Turco M*, Bizzoca G*, Tavoulari K*, Capodiferro S*, Escudero-Castaño N**, Lo Muzio L***

INTRODUCTION

The ameloblastoma is a relatively rare dental tumor,described for the first time by Broca in 1868, and sodenominated by Churchill in 1934.

According to Larsonn and Almeren (1), i tsincidence is 0,6 cases per million, while Shear andSingh (2) found an incidence of 0.31 cases permillion in a white population of Witwatersrand inSouth Africa. Between 1975 and the beginning ofthe ’80, the concept that the ameloblastoma existsin three different clinical/histopatological forms wasaccepted (3-4): solid-multicystical, unicystical andperipheral.

Reichart and Philipsen (5), in an analysis of the threepreviously mentioned entities, state that the averageage of the patients with ameloblastoma is 36 years.Gardner critesizing such review( 6), calculated a 39year-old average age for the solid multicystic amelo-blastoma, 22 for that unicystic ameloblastma and of51 years for the peripheral ameloblastoma. Equalincidences have been found in the two sexes byReichart.

MATERIAL AND METHODS

Ten cases (10) of ameloblastoma were identified inthe department of Dentistry and Surgery of the

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University of Bari-Italy between 1990 and 2006. Theywere evaluated and classified clinically, histologicallyand radiographycally, based on the cytological criteriaof Vickers and Gorlin (21) and World Health Orga-nization (25) guide lines.

The clinical-pathological data was evaluated: age, sex,site and dimensions of the lesion, primary andsecondary symptoms and radiographic aspects andcharacteristics. Furthermore the possible presenceand entity of recurrence in relationship to thehistological nature of the lesions was examined. Thesize of the tumor was measured from the panoramicradiograph and the greater mesio-distal and apico-occlusal diameters were recorded.

We also considered the type of treatment, results inrelationship to the hystological, clinical and pathol-ogical criteria of the various types of lesion, with afollow-up ranging from 1 to 15 years.

RESULTS

Frequency

10 cases of ameloblastoma were identified duringthis study. According to the hystological classification(25) we found: 8 solid-multicystic, 2 unicystic.

Age and gender: The average age of all the patients,during the diagnosis, was 39.6 years. The male/female relationship calculated for the whole groupwas 1,3:1, for the solid ameloblastomas 1,4:1 and1,25:1for the unicisticis ameloblastomas.

All the patients were of Caucasian race and of Italiannationality.

Site distribution

9 cases were located in the jaw and 1 in the uppermaxilla. The ratio between the upper maxilla and jawwas 9:1. In 7 cases the ameloblastoma was locatedin the posterior third of the maxillary bones,including the area of the molar teeth and thestructures distal to them. In 3 cases the tumor wasfound in the anterior and /or middle part of the

maxillary bones, therefore the region in front of thefirst molar.

Analysing the three histological types separately wefound that 7 of the 8 cases of solid ameloblastomawere located in the jaw, 1 of these in the posteriorthird, and 1 in the upper maxilla. All the unicysticameloblastomas (2) were located in the posterior thirdof the jaw.

Size of tumor

In all patients the mesio-distal dimensions weregreater than 2,5 cm (Figs. 1-3).

Symptoms

The symptoms were recorded in all cases: in 8patients the main symptom was a non aching swellingof the maxillary bones, 2 were accompanied by pain.In 4 cases the increase of volume of the lesion wasdescribed up until the hospitalisation; in 1 case painwas the only symptom. In 2 patients rhizolisi was

Fig. 1.

Fig. 2.



observed. Paraesthesia was observed only in 1 caseas a secondary symptom. In 2 cases we found thenon aching ulceration of the overlying oral mucosa(Fig. 4). In 4 cases the discovery of the lesion waschance, after performing an x-ray for other medicalpurposes. The average time between the debut tothe diagnosis was 9,7 months.

Radiographic findings

The radiographic aspect in 8 cases was multilocularand in 2 cases unilocular. In the case of maxillaryameloblastoma the opacity of the maxillary sinus wasobserved.

Histological findings

The histological diagnosis and the classificationbased on the actual criteria (25) allowed us toindentify 8 solid-multicistic amelobblastomas. Thesolid follicolar ameloblastoma were 4 (50%), theplessiforme 2 (25%), the acantomatosis 1 (12,5%)and the mixed 1 (12,5%). The 2 cases of unicystic

ameloblastoma were recognised and classified basedon the Ackerman classification into: 1 type III (50%)and 1 type II (50%).

Treatments and recurrence

The cases have been divided into 3 groups based onthe clinical entity ( multicystical or unicystical) andthe treatment received ( conservative or radical):

— Group 1: multicystic ameloblastoma with conser-vative therapy, (cases from 1 to 6).

— Group 2: multicystic ameloblastoma with radicaltherapy, (cases from 7 to 8).

— Group 3: unicystic ameloblastoma with conser-vative therapy (cases from 9 to 10).

Conservative surgical therapy included enucleation,curettage, electrocautery, excision and stitching. Ra-

Fig. 3.

Fig. 4.



dical surgery also includes marginal resection, seg-mental or total resection of the mandible with widemargins.

The analysis of the first group (6 patients) showed 3cases of recurrences. The average time between thetreatment and the recurrences was 3,5 years (range4 months-10 years).

2 of the 3 recurrences were treated again withconservative therapy.

In one case the treatment of the recurrence consistedin the resection of the jaw without continuity of theinferior edge and a bone autograft, which has notrecurred.

In the second group of solid ameloblastomas the 2patients were treated with radical surgery.

In this group the only case of recurrence was observedafter 5 years, in spite of the resection of the jaw withsolution of continuity of the inferior edge therecurrence was diagnosed and treated with a surgicalextension of the borders.

The third group with unicystic ameloblastomas, iscomposed of 2 patients with an initial conservativetreatment.

The unicystic ameloblastomas recurred in averageafter 3.5 years.

There was one recurrence in this group. It waspossible to reconstruct the following therapeutichistory: first treated with conservative therapy,recurred for the second time and a jaw resection withsolution of continuity of the inferior edge wasnecessary but successful.

Clinical and histological factors of risk forrecurrence

The first group (cases 1-6) had 3 recurrences out ofa total of 6 with dimensions greater than 2 cm at themoment hospitalisation and 1 recurrences haddimensions inferior than 2 cm at the time ofhospitalisation. In the second group (cases 7-8), 1

lesion out of 2 had dimensions greater than 3 cm atthe hospitalisation.

In the group of the unicystic ameloblastomas (cases9-10) the only recurrences had with dimensionsgreater than 3 cm at hospitalisation were observed.By each the location, in the first group we havenoticed only 3 recurrences out of a total of 6 withlocation in the anterior and middle third of themaxillary bones, while the remainder 3 lesions werelocated in the posterior third recurred. In the secondgroup there was only one lesion located in the poste-rior third.

In the group of the unicystic ameloblastoma, wefound one recurrence located in the posterior part ofthe jaw.

DISCUSSION

The ameloblastoma is statistically more frequent inthe molar region and branch of the jaw, while in themaxilla it is more often found in the molar region,even if in some cases the maxillary cavity is interested.

The 80% of these cases were solid-multicystical andthe remaining 20% unicystic. This data differ fromReicharts studies (5), which estimates 51% theincidence of the solid-multicystical lesion and the 49%for the unicystic. Such discrepancy can only bedetermined by the small amount of patientsconsidered in our study. From the analysis of ourcases an agreement emerged with Kramer and Regeziet, to the (11), we found no correlation among clinicalsymptoms, biological behavior and histologicalsubtype. According to Reichart (5) the most commonhistological type is the follicolar lesion 50% comparedto 33,9% proposed by literature.

According to Shaw and Katsikas (26) none of theircases followed chemio- or radiotherapy, which areonly indicated in case of remaining tumor tissue afterlesion resection or as a palliative therapy. In case ofupper maxillar lesions radical resection is advised,due to the spongy osteoarchitecture of the maxillawhich facilitates the diffusion of the tumor to thesinus ethmoidalis, pterygoidea fossa, temporal fossaand base of skull (21,25). In our study we had only



one case of ameloblastoma located in the uppermaxilla, it were treated with conservative surgery.Recurrences were encountered in the patients, thatwere over 65 years old, for whom this type oftreatment was chosen because of the limited life spanleft; but for the young patients the literature suggesta conservative approach in pediatric patients.

Considering the fact that the conservative treatmentof the maxillar bones offers local recurrence in100%of the cases and a 60% of mortality rate (26-28-32),it is important that the patients with this pathologyhave a life long follow-up with the help of computertomography (CT) and magnetic resonancetomography (MRT). The therapy of the ameloblasto-ma is surgical, but it has not been established yetwhich is the most suitable operation. The decision touse a radical or conservative approach depends onvarious factors: 1) the dimensions and the locationof the lesion, 2) the growth rate and the relationshipwith the nearby structures, 3) the histological type, 4)the clinical characteristics, in the recurrences, 5) thegeneral conditions of health and the age of the patient(14). Among this series of factors the histologicalaspect has a decisive role: the solid multicystic ame-loblastoma and the unicystic-intramural ameloblas-tomas, subtype III of Ackerman, need radicaltreatment, with the resection of 1-2 cm of healthybone (12-15-17), although not all the authors havefound high rates of recurrence after the conservativetreatment of such forms (5). On the contrary theunicystic intraluminal ameloblastoma rarely recurrersafter conservative therapy, only 10 % according toLeider (15), Eversole (16), Gardner (17) and 13,7%according to Reichart (5). Therefore a conservativeaproach it is advisable in the case of a non invasiveand non proliferating cyst wall. The location of thelesion seems to be an important risk factor for therecurrence of the ameloblastoma in fact the mostfrequent recurrence were located in the third poste-rior of the jaw.

CONCLUSION

We think that the product of our experience, is usefulfor an efficient programming of treatment, taking inconsideration numerous variables of this pathologyand the indications found in literature.

We believe that for the diagnostic phase the instru-mental examinations (X-RAY, CT or MRT) areessential; while intralesional byopsies are inefficientbecause they don ‘t offer a whole vision of the tumorand could lead to diagnostic error. Therefore we thinkthat it is advisable, considering: the site and extention,of the lesion, age and general conditions of thepatient, to remove the lesion in a conservative mannerin a first surgical step and according to the histolgicalaspect evaluate a possible radical resection.

BIBLIOGRAFÍA

1. Larsson A Ê, Almeren H. Ameloblastoma of thejaws. An analysis of a consecutive series of allcases reported to the Swedish Cancer Registryduring 1958-1971. Acta Pathologica et Micro-biologica Scandinavica (A) 1978;86:337-49.

2. Shear M, Singh S. Age-standardized incidencerates of ameloblastoma and dentigerous cyst onthe Witwatersrand, South Africa. CommunityDentistry and Oral Epidemiology 1978; 6:195-9.

3. Gardner DG, PecË sak AMJ. The treatment ofameloblastoma based on pathologic andanatomic principles. Cancer 1980; 46:2514-9.

4. Robinson L, Martinez MG. Unicystic ameloblas-toma: a prognostically distinct entity. Cancer1977;40:2278-85.

5. Reichart PA, Philipsen HP, Sonner S. Ameloblasto-ma: biological prole of 3677 cases. Oral Oncology,European Journal of Cancer 1995; 31B:86-99.

6. Critique of the 1995 review by Reichart et al.$ ofthe biologic erole of 3677 ameloblastomas D.G.Gardner Oral Oncology 1999;35:443-9.

7. Khan MA: Ameloblastoma in young persons: Aclinicopathologic analysis and etiologicinvestigation. Oral Surg Oral Med Oral Pathol1984; 67:706.

8. Eversole LR, Leider AS, Strub D. Radiographiccharacteristics of cystogenic ameloblastoma.Oral Sug Oral Med Oral Pathol 1984;57:572-7.



9. Gardner DG: Plexiform unicystic ameloblastoma:A diagnostic problem in dentigenous cysts.Cancer 1981; 47:1358.

10. Struthers P, Shear M: Root resorption by Amelo-blastomas and cysts of the jaws. Int J Oral Surg5:128, 1976.

11. 258 Kramer IR. Ameloblastoma: a clinico-pathological appraisal. Br J Oral Surg 1963;1:13-28.

12. Regezi JA, Kerr DA, Courtney RM. Odontogenictumors: analysis of 706 cases. J Oral Surg1978;36:771-8.

13. Ackerman GL, Altini M, Shear M: The unicysticameloblastoma: A clincopathological study of 57cases. J Oral Pathol 1988;17:541.

14. HP Philipsen A, PA Reichart BH. Nikai CT. TakataCY. Kudo. Review Peripheral ameloblastoma:biological role based on 160 cases from theliterature. Oral Oncology 2001; 37:17-27.

15. Ueno S, Nakamura S, Mushimoto K, Shirasu R.A clinicopathologic study of ameloblastoma.Journal Oral Maxillofacial Surgery 1986;44:361-5.

16. Waldron CA, El-Mofty SK. A histopathologic studyof 116 ameloblastomas with special reference tothe desmoplastic variant. Oral Surgery Oral Me-dicine Oral Pathology 1987;63:441-7.

17. Rick G, Howell F, Pindborg J. The peripheralAmeloblastoma: a clinicopathologic study of 18cases. Journal Oral Pathology 1985;14:85.

18. Niccoli-Filho W, Gomes da MGME, Raldi FV,Seraidarian PI. Peripheral ameloblastoma.Journal Nihon University School of Dentistry1997;39:34-7.

19. Buchner A, Sciubby JJ. Peripheral epithelialodontogenic tumors: a review. Oral Surgery OralMedicine Oral Pathology 1987;63:688-97.

20. Nauta JM, Panders AK, Schoots CJF, Vermey A,Roodenburg JLN. Peripheral ameloblastoma. A

case report and review of the literature.International Journal Oral Maxillofacial Surgery1992;21:40-4.

21. Vickers RA, Gorlin RJ. Ameloblastoma:delineation of early istopatologic features of neo-plasia. Cancer 1970;3, 699-710.

22. Kramer IRH, Pindborg JJ, Shear M. Histologicaltyping of odontogenic tumours. 2nd ed. Berlin:Springer-Verlag; 1992.

23. Leider AS, Eversole LR, Barkin ME. Cystic ame-loblastoma. A clinopathologic analysis. Oral SugOral Med Oral Pathol 1985;60:624-30.

24. Eversole LR, Leider AS, Strub D. Radiographiccharacteristics of cystogenic ameloblastoma.Oral Sug Oral Med Oral Pathol 1984;57:572-7.

25. Eggert JH, Steinhauser EW. Besonderheiten derOberkiefer-Ameloblastome Beobachtungen an12 Fallen. Fortschr Kiefer Gesichtschir 1986;31:101-4.

26. Shaw HJ, Katsikas DK. Ameloblastoma of themaxilla. A clinical study with four cases. JLaryngol Otol. 1973;87:873-84.

27. Eichhorn T, Glanz H, Kleinsasser O. Amelo-blastome des Oberkiefers. Bericht uber 6 Falleund Literaturzusammenstellung. HNO 1982;30:1-8.

28. Batsakis JG, Mclatchey KD. Ameloblastoma ofthe maxilla and paripheral ameloblastomas. AmOtol Rhinol Laryngol 1983;92:532-4.

29. Pilz G, Nitzschke M. Uber die Spatrezidivierungder Ameloblastome. Stomatol DDR 1979;29:107-11.

30. Sandler KA, Novo RM, Rudner BE. A study ofameloblastoma- age, sex, location statistics. NYState Dent J 1983; 49: 682-4.

31. Young DR, Robinson M, Ameloblastoma inchildren: report of a case. Oral Sug Oral MedOral Pathol 1962; 15: 1155-62.



32. Sehdev MK, Huvos AG, Strong EW, Gerold FP,Willis GW. Proceedings: Ameloblastoma ofmaxilla and mandible. Cancer 1974; 33: 324-33.

33. Menakanit W. Ameloblastoma of the jaw: a 10year analysis (1966-1975). J med Assoc Thai1979; 62: 6-9.

34. Gardner DG. A pathologyst’s approach to thetreatment of ameloblastoma. J Oral MaxillofacSurg 1984; 43: 161-6.

35. Philipsen HP, Reichart PA. Revision of the 1992edition of the WHO histological typing of odonto-genic tumors. A suggestion. J Oral Pathol Med2002;31:253-8.

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Ameloblastoma of the jaw and maxillary bone: clinical study and