404
ADENOMATOID
J Oral Maxlllofac
ODONTOGENIC
TUMOR IN JAPAN
Surg
4.3:404-408, 1990
Adenomatoid
Odontogenic
Tumor:
Report of Two Cases and Survey of 126 Cases in Japan MAKOTO TOIDA, DDS, DMSc,* IWAO HYODO, DDS,t TAKASHI OKUDA, DDS,t AND NORICHIKA TATEMATSU, DDS, DMScS
The adenomatoid odontogenic tumor (AOT) is a benign epithelial tumor that accounts for only 3% of all odontogenic tumors.’ Several excellent reviews2-4 of this rare tumor have been published in the English language literature, in which 168 cases had been reported as of 1981. In Japan, 124 cases had been reported as of 1988. The object of this report is to present two new cases of AOT, to elucidate the clinical features of this tumor in Japan, and to briefly compare the latter findings with those reported in the world literature. Report of Two Cases Case 1 A 12-year-old Japanese girl was referred to our department on August 19, 1988, with a chief complaint of the prolonged retention of the upper right deciduous canine and second molar. Radiographic examination showed the unerupted upper right permanent canine and second premolar teeth and a well-circumscribed radiolucent lesion around the crown of the former (Fig 1). The lesion was diagnosed clinically as a dentigerous cyst. Both deciduous teeth were extracted on August 23. The cystic lesion was enucleated under local anesthesia on September 15. Fenestration was done simultaneously, expecting the eruption of both embedded permanent teeth. Although there was no sign of recurrence 9 months after the operation, neither of the permanent teeth has erupted spontaneously. We have since attempted moving these unerupted teeth to their normal position using an orthodontic appliance.
Case 2 A 12-year-old Japanese boy visited a dental practitioner on August 24, 1982, with a chief complaint of prolonged
retention of the lower left deciduous lateral incisor and canine and delayed eruption of the lower left permanent lateral incisor, canine, and first premolar. The cystic lesion surrounding the unerupted permanent teeth was discovered by the dentist on the panoramic radiograph, and the patient was referred to our department on August 25. The patient’s medical history was noncontributory. Intraoral examination revealed a firm, ill-defined, tender swelling in the mucolabial and mucobuccal fold, extending from the lower left deciduous lateral incisor and canine to the permanent second premolar region. Radiographic examination showed a well-demarcated radiolucent lesion surrounding the unerupted lower left lateral incisor and canine (Fig 2). It extended to the lower right central incisor region, but the unerupted first premolar was not involved. There was no radiopacity within the lesion. The lesion was diagnosed clinically as a dentigerous cyst. The patient was admitted on September 6, 1982. On September 9, under general anesthesia, the lesion was enucleated and the unerupted lateral incisor and canine were extracted. Simultaneously, the bone overlying the first premolar was removed to facilitate eruption of the tooth. Neither of the lower left deciduous teeth was extracted. The patient left the hospital on September 9. Fenestration was done again on November 2, expecting the eruption of the first premolar. The tooth had erupted to almost-normal position on December 27, 1983 (Fig 3). Endodontic therapy of the infected root canals and root canal filling of the lower left deciduous lateral incisor and canine were done on January 13, 1984. The patient was free from paresthesia of the left lower lip and mental region on February 22, 1989. Radiographic examination, however, showed a small, well-defined radiolucent lesion, measuring approximately 5 mm in diameter, close to, but separated from, the apex of the deciduous canine (Fig 4). Recurrence of the AOT was suspected. However, the patient did not return for further examination.
PATHOLOGIC
Received from the Department of Oral and Maxillo-Facial Surgery, Gifu University School of Medicine, Gifu, Japan. * Lecturer. t Assistant. .t Assistant Professor. Address correspondence and reprint requests to Dr Toida: Department of Oral and Maxilla-Facial Surgery, Gifu University School of Medicine, Tsukasa-machi, Gifu 500, Japan. 0 1990 American
Association
geons 0278-2391/90/4804-0014$3.00/O
of Oral and Maxillofacial
Sur-
FINDINGS
Grossly, the surgical specimen in case no. 1 was a tancolored cystic sac measuring approximately 10 mm in diameter. The cyst wall was about 3 mm thick. In case no. 2, the specimen was a tan-colored, elastic soft tissue measuring 30 x 20 x 20 mm, involving two permanent teeth. When it was cut, tiny cystic cavities were seen around the teeth. Gritty sandlike material was scattered throughout the thick cyst wall. In both cases, numerous small granules and nodules were seen on the inner surface of the cystic sac, whereas the outer surface was smooth. Histological examination revealed that the cyst wall
TOIDA ET Al,
FIGURE 3. Photograph of intraoral condition 1 year, 2 months after the operation (case 2). Retention of the deciduous lower left lateral incisor and canine is seen. The lower left first premolar is present in almost-normal position.
FIGURE 1. Radiograph showing a well-circumscribed radiolucent lesion around the coronal portion of the unerupted upper right canine (case 1). The second premolar is also unerupted.
was composed of thick, hyalinized connective tissue (Fig 5) lined by a single or double layer of columnar or cuboi-
da1 epithelial cells with irregular papillary growth into the cystic cavity (Fig 6). Within the cystic cavity, nodular epithelial masses were also seen (Fig 5). In these nodules, solid proliferation of polygonal and spindle-shaped tumor cells, with only scanty stroma of connective tissue, was observed (Figs 5 and 7). In places, ductlike and rosette-
like structures were also seen (Figs 7 and 8). The nuclei of the columnar cells composing these structures were polarized away from the lumina. Deposition of eosinophilic homogeneous material was also seen within the lumina of some rosettelike structures (Fig 7). Small foci and masses of calcification were seen scattered throughout the tumor tissue as well as in the connective tissue (Fig 5). The lesions in both cases were diagnosed as adenomatoid odontogenic tumor.
Discussion
done in 1981 by Stroncek et a1,4 who surveyed 168 cases reported in the world literature, including all cases of Giansanti et al and 2 new Japanese cases. In 1985, Takahashi et al6 reviewed 89 cases of AOT occurring in Japanese. Since then, 35 other Japanese cases have been reported. Adding the 2 present cases, we have accumulated 126 Japanese cases. A review of these 126 cases reveals that the lesion is most frequently encountered in the second decade of life, and 101 (about 81%) of 124 patients were under 30 years (Table 1). The mean age was 19 years, with a range from 3’ to 718 years. There were 93 females and 31 males; in 2 cases the sex of the patients was not mentioned. The maxilla was the site of involvement in 73 cases (58%) and the mandible in the remaining 53 cases (42%). No apparent case of the extraosseous counterpart of this tumor has been reported in Japan. An intraoral or extraoral swelling was the main symptom, and the swelling was usually painless and slowly growing. The radiographs generally showed
Adenomatoid odontogenic tumor was first recognized as a distinct entity by Stafnes in 1948. In 1970, Giansanti et al2 reviewed 111 cases of this rare tumor, including 3 of their own and 19 Japanese cases. The most comprehensive review of AOT was
FIGURE 2. Radiograph showing a well-circumscribed radiolucent lesion involving the unerupted lower left lateral incisor and canine (case 2). The first premolar is also unerupted.
FIGURE 4. Radiograph showing a small, well-defined radiolucent lesion close to, but separated from, the apex of the deciduous canine (case 2).
FIGURE 5. Cyst wall composed of connective tissue and lined by an epithelial layer (left half) and nodular proliferation of tumor cells (right half). Small foci and masses of calcification are seen scattered throughout the neoplastic island and connective tissue (case 1). (Hematoxylin-eosin stain. Original magnification, X80.)
FIGURE 6. A single and double layer of the columnar and cuboida1 cells with irregular papillary growth into the cystic cavity (case 1). (Hematoxylin-eosin stain. Original magnification, x 180.)
FIGURE 7. Solid proliferation of polygonal and spindle-shaped cells associated with rosettelike and ductlike structures. Deposition of eosinophilic homogeneous material is also seen within the rosettelike structure (case 2). (Hematoxylin-eosin stain. Original magnification, x 180.)
407
TOIDA ET AL
FIGURE 8. A rosettelike structure composed of ameloblastlike columnar cells exhibiting a characteristic polarization of their nuclei (case 2). (Hematoxylin-eosin stain. Original magnification, X 360.)
a well-demarcated radiolucency with or without irregular intralesional radiopacity. Radiopacity was seen in 53 (approximately 78%) of 68 cases of AOT; Giansanti et al2 reported it in 34 (65%) of 52 cases. Unerupted teeth were associated with the tumor in 86 (73%) of 118 cases. All were permanent teeth, except for 2 deciduous teeth (Table 2); only 1 case of AOT surrounding the coronal portion of an unerupted deciduous upper canine and first molar of a 3-year-old boy has been reported.’ This is also the youngest reported case, as far as we know. The canine was the tooth most commonly involved (Table 2). In 1S of the 86 cases, besides the present case no. 2, more than one unerupted tooth was associated with the tumor. The clinical features of AOT occurring in our series of Japanese cases were essentially similar to those reported in the world literature evaluated by Stroncek et al.4 However, there are three significant Table 1. Age DistributSon by Decades of 126 Cases of AOT in Japan AgeW o-9 to-19 20-29 30-39 40-49 50-59 60-69 70-79 80Total Not mentioned
No. of Cases 6 74 31 6 4 0 2
1 0 124 2
differences. First, the lesion was found three times more frequently in females than in males in our series, but only two times more frequently in the series of Stroncek et al. Second, there were no extraosseous AOTs in our series, but eight cases in theirs. Third, there was one case of AOT associated with unerupted deciduous teeth in our series, but none in theirs. Preoperatively, the AOT has been diagnosed as various types of diseases (Table 3) because of the variety of the clinical and radiographic features of the lesion. It was diagnosed most frequently as a dentigerous cyst in 41 (45%) of 92 cases, and correctly as an AOT in only 8 cases (Table 3). In the present cases, both lesions were diagnosed preoperatively as dentigerous cysts because both appeared so radiographically; both were associated with unerupted teeth and not with intralesional radiopacity. Retrospectively, however, more careful observation of the radiogram in case no. 2 showed that the radiolucency associated with the lesion extended to the apical regions of the unerupted teeth (Fig 2); such a phenomenon occurs frequently in AOT2 and not in dentigerous cysts. Also, in case no. 1, the possibility of AOT should have been considered in the differential diagnosis, because AOT most frequently occurs as a dentigerous cyst-like lesion associated with an unerupted maxillary canine, especially in a female in the second and third decades of life. Histologically, both of the present lesions exhibited characteristic features of AOT. A single or double layer of columnar or cuboidal cells lining the cyst wall was seen in both cases, and such findings
408 Table
ADENOMATOID
2.
ODONTOGENIC
TUMOR IN JAPAN
Number of Unerupted Teeth Associated With AOT
Teeth
1
2
3
4
Maxillary Mandibular
2 2
16 7
29 18
9 7
5
Table 3. Preoperative Diagnosis of 126 Cases of AOT in Japan Diagnosis
Dentigerous cyst Adenomatoid odontogenic tumor Calcifying odontogenic cyst Benign tumor Odontogenic tumor Intraosseous cyst Odontogenic cyst Globulo-maxillary cyst Ameloblastoma Odontoma Residual cyst Epulis Tumor Hemangioma Pleomorphic adenoma Odontogenic tumor or cyst Fibrous dysplasia Total Not described
I
1
have been observed also by Okada et a1.9 The combination of AOT with other odontogenic tumors, including calcifying epithelial odontogenic tumor (CEOT),9-11 calcifying odontogenic cyst (COC),8312 and ameloblastoma,i2 has been reported in the Japanese literature. In the literature from other countries, three cases of combined occurrence of AOT and CEOT have been reported. ‘3-15In both present cases, a combined occurrence was not observed histologically. Enucleation and curettage is the most common treatment for this tumor, and there were no recurrent cases in the series of Stroncek et a14; even in the COC, at least seven recurrent cases have been reported.16 Thus, it is suggested that the AOT may be a hamartomatous lesion rather than a true neoplasm. There were, however, two cases of recurrent AOT reported in the Japanese literature17.‘8; growth of the AOT from the maxilla into the intracranial region has been also reported in one of the cases. I8 Therefore, careful follow-up examinations should be conducted in this disease. In the present case no. 2, a finding suggesting recurrence of the AOT was seen on the radiogram taken 7 years 5 months after the initial operation. Reoperation should have been done, but unfortunately the patient did not return for follow-up examination.
Preoperative
6
No. of Cases 41 8 I 7 6 4 3 3 2 2 2 2 1 1
1 1 1 92 34
8 2 3
C 1
D 1
Not Described 1 3
Acknowledgment The authors thank Professor Dr Nobumitsu Oka, Chief of the Department of Oral and Maxillo-Facial Surgery, Gifu University School of Medicine, for his guidance and suggestions.
References 1. Regezi JA, Kerr DA, Courtney RM: Odontogenic tumors: Analysis of 706 cases. J Oral Surg 36:771, 1978 2. Giansanti GS, Someren A, Waldron CA: Odontogenic adenomatoid tumor (adenoameloblastoma). Survey of 111 cases. Oral Surg Oral Med Oral Path01 30:69. 1970 3. Courtney RM, Kerr DA: The odontogenic adenomatoid tumor. A comprehensive study of twenty new cases. Oral Surg Oral Med Oral Path01 39:424. 1975 4. Stroncek GG, Acevedo A, Higa LH: An atypical odontogenit adenomatoid tumor and review of the literature. J Oral Med 36:102, 1981 5. Stafne EC: Epithelial tumours associated with developmental cysts of the maxilla. A report of three cases. Oral Surg Oral Med Oral Path01 1:887, 1948 6. Takahashi K, Yoshida H, Tokura H, et al: A case of adenomatoid odontogenic tumor of the maxilla and review of the literature. Jpn J Oral Maxillofac Surg 31: 1893, 1985 7. Mizukoshi T, Ojima I, Mizuno Y, et al: A case of adenomatoid odontogenic tumor occurring in a 3-year-old boy. J Jpn Stomatol Sot 29:605, 1980 8. Takada K, Adachi F, Nemoto R, et al: A case of combined epithelial odontogenic tumor. Jpn J Oral Maxillofac Surg 31:1981, 1985 9. Okada Y, Mochizuki K, Sugimura M, et al: Odontogenic tumor with combined characteristics of adenomatoid odontogenic and calcifying epithelial odontogenic tumors. Path01 Res Pratt 182:647, 1987 10. Nakamura T, Kimura Y, Wada A, et al: A case of Pindborg tumor combined with adenomatoid odontogenic tumor. J Jpn Stomatol Sot 36: 1074, 1987 11. Takeda Y, Kudo K: Adenomatoid odontogenic tumor associated with calcifying epithelial odontogenic tumor. Int J Oral Maxillofac Surg 15:469, 1986 12. Ando T, Noguchi I, Ide F. et al: A case of calcifying odontogenic cyst with ameloblastomatous proliferation and adenomatoid odontogenic tumor-like proliferation. Jpn J Oral Maxillofac Surg 3 1: 1930, 1985 13. Damm DD, White DK, Drummond JF, et al: Combined epithelial odontogenic tumor: Adenomatoid odontogenic tumor and calcifying epithelial odontogenic tumor. Oral Surg Oral Med Oral Path01 55:487, 1983 14. Bingham RA, Adrian JC: Combined epithelial odontogenic tumor-Adenomatoid odontogenic tumor and calcifying epithelial odontogenic tumor: Report of a case. J Oral Maxillofac Surg 44574, 1986 15. Siar CH, Ng KH: Combined calcifying epithelial odontogenit and adenomatoid odontogenic tumor. Int J Oral Maxillofac Surg 16:214, 1987 16. Wright BA, Bhardwaj AK, Murphy D: Recurrent calcifying odontogenic cyst. Oral Surg Oral Med Oral Path01 58:579. 1984 17. Fukaya M, Sato M, Umakoshi H, et al: A case report of adenoameloblastoma on the maxilla. Jpn J Oral Maxillofat Surg 17:155, 1971 18. Takigami M, Ueda T, Imaizumi T, et al: A case of adenomatoid odontogenic tumor with intracranial extension. No Shinkei Geka 16:775. 1988
ADENOMATOID
J Oral Maxlllofac
ODONTOGENIC
TUMOR IN JAPAN
Surg
4.3:404-408, 1990
Adenomatoid
Odontogenic
Tumor:
Report of Two Cases and Survey of 126 Cases in Japan MAKOTO TOIDA, DDS, DMSc,* IWAO HYODO, DDS,t TAKASHI OKUDA, DDS,t AND NORICHIKA TATEMATSU, DDS, DMScS
The adenomatoid odontogenic tumor (AOT) is a benign epithelial tumor that accounts for only 3% of all odontogenic tumors.’ Several excellent reviews2-4 of this rare tumor have been published in the English language literature, in which 168 cases had been reported as of 1981. In Japan, 124 cases had been reported as of 1988. The object of this report is to present two new cases of AOT, to elucidate the clinical features of this tumor in Japan, and to briefly compare the latter findings with those reported in the world literature. Report of Two Cases Case 1 A 12-year-old Japanese girl was referred to our department on August 19, 1988, with a chief complaint of the prolonged retention of the upper right deciduous canine and second molar. Radiographic examination showed the unerupted upper right permanent canine and second premolar teeth and a well-circumscribed radiolucent lesion around the crown of the former (Fig 1). The lesion was diagnosed clinically as a dentigerous cyst. Both deciduous teeth were extracted on August 23. The cystic lesion was enucleated under local anesthesia on September 15. Fenestration was done simultaneously, expecting the eruption of both embedded permanent teeth. Although there was no sign of recurrence 9 months after the operation, neither of the permanent teeth has erupted spontaneously. We have since attempted moving these unerupted teeth to their normal position using an orthodontic appliance.
Case 2 A 12-year-old Japanese boy visited a dental practitioner on August 24, 1982, with a chief complaint of prolonged
retention of the lower left deciduous lateral incisor and canine and delayed eruption of the lower left permanent lateral incisor, canine, and first premolar. The cystic lesion surrounding the unerupted permanent teeth was discovered by the dentist on the panoramic radiograph, and the patient was referred to our department on August 25. The patient’s medical history was noncontributory. Intraoral examination revealed a firm, ill-defined, tender swelling in the mucolabial and mucobuccal fold, extending from the lower left deciduous lateral incisor and canine to the permanent second premolar region. Radiographic examination showed a well-demarcated radiolucent lesion surrounding the unerupted lower left lateral incisor and canine (Fig 2). It extended to the lower right central incisor region, but the unerupted first premolar was not involved. There was no radiopacity within the lesion. The lesion was diagnosed clinically as a dentigerous cyst. The patient was admitted on September 6, 1982. On September 9, under general anesthesia, the lesion was enucleated and the unerupted lateral incisor and canine were extracted. Simultaneously, the bone overlying the first premolar was removed to facilitate eruption of the tooth. Neither of the lower left deciduous teeth was extracted. The patient left the hospital on September 9. Fenestration was done again on November 2, expecting the eruption of the first premolar. The tooth had erupted to almost-normal position on December 27, 1983 (Fig 3). Endodontic therapy of the infected root canals and root canal filling of the lower left deciduous lateral incisor and canine were done on January 13, 1984. The patient was free from paresthesia of the left lower lip and mental region on February 22, 1989. Radiographic examination, however, showed a small, well-defined radiolucent lesion, measuring approximately 5 mm in diameter, close to, but separated from, the apex of the deciduous canine (Fig 4). Recurrence of the AOT was suspected. However, the patient did not return for further examination.
PATHOLOGIC
Received from the Department of Oral and Maxillo-Facial Surgery, Gifu University School of Medicine, Gifu, Japan. * Lecturer. t Assistant. .t Assistant Professor. Address correspondence and reprint requests to Dr Toida: Department of Oral and Maxilla-Facial Surgery, Gifu University School of Medicine, Tsukasa-machi, Gifu 500, Japan. 0 1990 American
Association
geons 0278-2391/90/4804-0014$3.00/O
of Oral and Maxillofacial
Sur-
FINDINGS
Grossly, the surgical specimen in case no. 1 was a tancolored cystic sac measuring approximately 10 mm in diameter. The cyst wall was about 3 mm thick. In case no. 2, the specimen was a tan-colored, elastic soft tissue measuring 30 x 20 x 20 mm, involving two permanent teeth. When it was cut, tiny cystic cavities were seen around the teeth. Gritty sandlike material was scattered throughout the thick cyst wall. In both cases, numerous small granules and nodules were seen on the inner surface of the cystic sac, whereas the outer surface was smooth. Histological examination revealed that the cyst wall
TOIDA ET Al,
FIGURE 3. Photograph of intraoral condition 1 year, 2 months after the operation (case 2). Retention of the deciduous lower left lateral incisor and canine is seen. The lower left first premolar is present in almost-normal position.
FIGURE 1. Radiograph showing a well-circumscribed radiolucent lesion around the coronal portion of the unerupted upper right canine (case 1). The second premolar is also unerupted.
was composed of thick, hyalinized connective tissue (Fig 5) lined by a single or double layer of columnar or cuboi-
da1 epithelial cells with irregular papillary growth into the cystic cavity (Fig 6). Within the cystic cavity, nodular epithelial masses were also seen (Fig 5). In these nodules, solid proliferation of polygonal and spindle-shaped tumor cells, with only scanty stroma of connective tissue, was observed (Figs 5 and 7). In places, ductlike and rosette-
like structures were also seen (Figs 7 and 8). The nuclei of the columnar cells composing these structures were polarized away from the lumina. Deposition of eosinophilic homogeneous material was also seen within the lumina of some rosettelike structures (Fig 7). Small foci and masses of calcification were seen scattered throughout the tumor tissue as well as in the connective tissue (Fig 5). The lesions in both cases were diagnosed as adenomatoid odontogenic tumor.
Discussion
done in 1981 by Stroncek et a1,4 who surveyed 168 cases reported in the world literature, including all cases of Giansanti et al and 2 new Japanese cases. In 1985, Takahashi et al6 reviewed 89 cases of AOT occurring in Japanese. Since then, 35 other Japanese cases have been reported. Adding the 2 present cases, we have accumulated 126 Japanese cases. A review of these 126 cases reveals that the lesion is most frequently encountered in the second decade of life, and 101 (about 81%) of 124 patients were under 30 years (Table 1). The mean age was 19 years, with a range from 3’ to 718 years. There were 93 females and 31 males; in 2 cases the sex of the patients was not mentioned. The maxilla was the site of involvement in 73 cases (58%) and the mandible in the remaining 53 cases (42%). No apparent case of the extraosseous counterpart of this tumor has been reported in Japan. An intraoral or extraoral swelling was the main symptom, and the swelling was usually painless and slowly growing. The radiographs generally showed
Adenomatoid odontogenic tumor was first recognized as a distinct entity by Stafnes in 1948. In 1970, Giansanti et al2 reviewed 111 cases of this rare tumor, including 3 of their own and 19 Japanese cases. The most comprehensive review of AOT was
FIGURE 2. Radiograph showing a well-circumscribed radiolucent lesion involving the unerupted lower left lateral incisor and canine (case 2). The first premolar is also unerupted.
FIGURE 4. Radiograph showing a small, well-defined radiolucent lesion close to, but separated from, the apex of the deciduous canine (case 2).
FIGURE 5. Cyst wall composed of connective tissue and lined by an epithelial layer (left half) and nodular proliferation of tumor cells (right half). Small foci and masses of calcification are seen scattered throughout the neoplastic island and connective tissue (case 1). (Hematoxylin-eosin stain. Original magnification, X80.)
FIGURE 6. A single and double layer of the columnar and cuboida1 cells with irregular papillary growth into the cystic cavity (case 1). (Hematoxylin-eosin stain. Original magnification, x 180.)
FIGURE 7. Solid proliferation of polygonal and spindle-shaped cells associated with rosettelike and ductlike structures. Deposition of eosinophilic homogeneous material is also seen within the rosettelike structure (case 2). (Hematoxylin-eosin stain. Original magnification, x 180.)
407
TOIDA ET AL
FIGURE 8. A rosettelike structure composed of ameloblastlike columnar cells exhibiting a characteristic polarization of their nuclei (case 2). (Hematoxylin-eosin stain. Original magnification, X 360.)
a well-demarcated radiolucency with or without irregular intralesional radiopacity. Radiopacity was seen in 53 (approximately 78%) of 68 cases of AOT; Giansanti et al2 reported it in 34 (65%) of 52 cases. Unerupted teeth were associated with the tumor in 86 (73%) of 118 cases. All were permanent teeth, except for 2 deciduous teeth (Table 2); only 1 case of AOT surrounding the coronal portion of an unerupted deciduous upper canine and first molar of a 3-year-old boy has been reported.’ This is also the youngest reported case, as far as we know. The canine was the tooth most commonly involved (Table 2). In 1S of the 86 cases, besides the present case no. 2, more than one unerupted tooth was associated with the tumor. The clinical features of AOT occurring in our series of Japanese cases were essentially similar to those reported in the world literature evaluated by Stroncek et al.4 However, there are three significant Table 1. Age DistributSon by Decades of 126 Cases of AOT in Japan AgeW o-9 to-19 20-29 30-39 40-49 50-59 60-69 70-79 80Total Not mentioned
No. of Cases 6 74 31 6 4 0 2
1 0 124 2
differences. First, the lesion was found three times more frequently in females than in males in our series, but only two times more frequently in the series of Stroncek et al. Second, there were no extraosseous AOTs in our series, but eight cases in theirs. Third, there was one case of AOT associated with unerupted deciduous teeth in our series, but none in theirs. Preoperatively, the AOT has been diagnosed as various types of diseases (Table 3) because of the variety of the clinical and radiographic features of the lesion. It was diagnosed most frequently as a dentigerous cyst in 41 (45%) of 92 cases, and correctly as an AOT in only 8 cases (Table 3). In the present cases, both lesions were diagnosed preoperatively as dentigerous cysts because both appeared so radiographically; both were associated with unerupted teeth and not with intralesional radiopacity. Retrospectively, however, more careful observation of the radiogram in case no. 2 showed that the radiolucency associated with the lesion extended to the apical regions of the unerupted teeth (Fig 2); such a phenomenon occurs frequently in AOT2 and not in dentigerous cysts. Also, in case no. 1, the possibility of AOT should have been considered in the differential diagnosis, because AOT most frequently occurs as a dentigerous cyst-like lesion associated with an unerupted maxillary canine, especially in a female in the second and third decades of life. Histologically, both of the present lesions exhibited characteristic features of AOT. A single or double layer of columnar or cuboidal cells lining the cyst wall was seen in both cases, and such findings
408 Table
ADENOMATOID
2.
ODONTOGENIC
TUMOR IN JAPAN
Number of Unerupted Teeth Associated With AOT
Teeth
1
2
3
4
Maxillary Mandibular
2 2
16 7
29 18
9 7
5
Table 3. Preoperative Diagnosis of 126 Cases of AOT in Japan Diagnosis
Dentigerous cyst Adenomatoid odontogenic tumor Calcifying odontogenic cyst Benign tumor Odontogenic tumor Intraosseous cyst Odontogenic cyst Globulo-maxillary cyst Ameloblastoma Odontoma Residual cyst Epulis Tumor Hemangioma Pleomorphic adenoma Odontogenic tumor or cyst Fibrous dysplasia Total Not described
I
1
have been observed also by Okada et a1.9 The combination of AOT with other odontogenic tumors, including calcifying epithelial odontogenic tumor (CEOT),9-11 calcifying odontogenic cyst (COC),8312 and ameloblastoma,i2 has been reported in the Japanese literature. In the literature from other countries, three cases of combined occurrence of AOT and CEOT have been reported. ‘3-15In both present cases, a combined occurrence was not observed histologically. Enucleation and curettage is the most common treatment for this tumor, and there were no recurrent cases in the series of Stroncek et a14; even in the COC, at least seven recurrent cases have been reported.16 Thus, it is suggested that the AOT may be a hamartomatous lesion rather than a true neoplasm. There were, however, two cases of recurrent AOT reported in the Japanese literature17.‘8; growth of the AOT from the maxilla into the intracranial region has been also reported in one of the cases. I8 Therefore, careful follow-up examinations should be conducted in this disease. In the present case no. 2, a finding suggesting recurrence of the AOT was seen on the radiogram taken 7 years 5 months after the initial operation. Reoperation should have been done, but unfortunately the patient did not return for follow-up examination.
Preoperative
6
No. of Cases 41 8 I 7 6 4 3 3 2 2 2 2 1 1
1 1 1 92 34
8 2 3
C 1
D 1
Not Described 1 3
Acknowledgment The authors thank Professor Dr Nobumitsu Oka, Chief of the Department of Oral and Maxillo-Facial Surgery, Gifu University School of Medicine, for his guidance and suggestions.
References 1. Regezi JA, Kerr DA, Courtney RM: Odontogenic tumors: Analysis of 706 cases. J Oral Surg 36:771, 1978 2. Giansanti GS, Someren A, Waldron CA: Odontogenic adenomatoid tumor (adenoameloblastoma). Survey of 111 cases. Oral Surg Oral Med Oral Path01 30:69. 1970 3. Courtney RM, Kerr DA: The odontogenic adenomatoid tumor. A comprehensive study of twenty new cases. Oral Surg Oral Med Oral Path01 39:424. 1975 4. Stroncek GG, Acevedo A, Higa LH: An atypical odontogenit adenomatoid tumor and review of the literature. J Oral Med 36:102, 1981 5. Stafne EC: Epithelial tumours associated with developmental cysts of the maxilla. A report of three cases. Oral Surg Oral Med Oral Path01 1:887, 1948 6. Takahashi K, Yoshida H, Tokura H, et al: A case of adenomatoid odontogenic tumor of the maxilla and review of the literature. Jpn J Oral Maxillofac Surg 31: 1893, 1985 7. Mizukoshi T, Ojima I, Mizuno Y, et al: A case of adenomatoid odontogenic tumor occurring in a 3-year-old boy. J Jpn Stomatol Sot 29:605, 1980 8. Takada K, Adachi F, Nemoto R, et al: A case of combined epithelial odontogenic tumor. Jpn J Oral Maxillofac Surg 31:1981, 1985 9. Okada Y, Mochizuki K, Sugimura M, et al: Odontogenic tumor with combined characteristics of adenomatoid odontogenic and calcifying epithelial odontogenic tumors. Path01 Res Pratt 182:647, 1987 10. Nakamura T, Kimura Y, Wada A, et al: A case of Pindborg tumor combined with adenomatoid odontogenic tumor. J Jpn Stomatol Sot 36: 1074, 1987 11. Takeda Y, Kudo K: Adenomatoid odontogenic tumor associated with calcifying epithelial odontogenic tumor. Int J Oral Maxillofac Surg 15:469, 1986 12. Ando T, Noguchi I, Ide F. et al: A case of calcifying odontogenic cyst with ameloblastomatous proliferation and adenomatoid odontogenic tumor-like proliferation. Jpn J Oral Maxillofac Surg 3 1: 1930, 1985 13. Damm DD, White DK, Drummond JF, et al: Combined epithelial odontogenic tumor: Adenomatoid odontogenic tumor and calcifying epithelial odontogenic tumor. Oral Surg Oral Med Oral Path01 55:487, 1983 14. Bingham RA, Adrian JC: Combined epithelial odontogenic tumor-Adenomatoid odontogenic tumor and calcifying epithelial odontogenic tumor: Report of a case. J Oral Maxillofac Surg 44574, 1986 15. Siar CH, Ng KH: Combined calcifying epithelial odontogenit and adenomatoid odontogenic tumor. Int J Oral Maxillofac Surg 16:214, 1987 16. Wright BA, Bhardwaj AK, Murphy D: Recurrent calcifying odontogenic cyst. Oral Surg Oral Med Oral Path01 58:579. 1984 17. Fukaya M, Sato M, Umakoshi H, et al: A case report of adenoameloblastoma on the maxilla. Jpn J Oral Maxillofat Surg 17:155, 1971 18. Takigami M, Ueda T, Imaizumi T, et al: A case of adenomatoid odontogenic tumor with intracranial extension. No Shinkei Geka 16:775. 1988
