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Recurrent ameloblastoma of the mandible
J. rnax.-fac. Surg. 4 (1976) 1-7 © Georg Thieme Verlag, Stuttgart
Recurrent Ameleblastoma of the Mandible* Ian Smith Department of Maxillo-Facial and Oral Surgery (Head: I. Smith, B.D.S., L.R.C.P., L.R.C.S., F.D.S.R.C.S.) Johannesburg General Hospital and Univ. of the Witwatersrand, S. Africa
Summary Amelobtastoma is by nature an invasive tumour and the full extent of the infiltration is not always appreciated when the lesion is being excised. Included in a series of 40 cases are 7 recurrent lesions. Pertinent clinical features of the 7 recurrent cases are discussed. A close study has been made of the recurrent tumours in the hope that some explanation could be found for the unsuccessful primary treatment. The investigation considered a number of aspects of the behavior of this growth and from this certain facts have emerged. Definitive treatment should not be embarked on before the diagnosis has been established. Only then can an overall plan of management be devised. It is noteworthy that the rate of growth of the lesion is more rapid in the younger age group. Ameloblastoma varies in it's clinical and radiological presentation. Primary treatment is influenced by the size and site of the particular lesion. The management of the recurrent lesion depends on the anode of presentation of the particular growth.
Key-Words: Ameloblastoma of mandible; Recurrency. Introduction Ameloblastoma is by nature an invasive tumour and unfortunately the full extent of the infiltration is not always appreciated at the time of treatment, even though the clinical and radiological examinations have been thorough. In spite of what could appear to the surgeon to be an adequate excision, the occasion will arise when microscopic remnants of the growth will be missed, and it is from these loci that the tumour will continue to grow. From a series of 40 cases that have had treatment in our department it is possible to d r a w some conclusions as to the behavior of this growth and to make further comments about the management of this condition. Included in this series of 40 cases are 7 recurrent lesions. Of these, 6 patients had p r i m a r y treatment "* Paper read at I.A.D.R. Congress, Cape Town, Oct. 1974. 1 ], max.-fac.Surg. 1/76
elsewhere, while the remaining one received the initial treatment in our department. 5 lesions took an average of 10 years to r e a p p e a r as significant growths. 1 took 20 years to recur after what was described from the records to have been a local excision as the p r i m a r y method of treatment. The 7th. patient, who was first treated in our unit, returned with an extensive recurrence of the growth within 4 years of the initial treatment.
Clinical Material The mode of presentation of the 7 recurrent lesions was dependent on the site of origin of the recurrence. 3 lesions recurred in the stump in the symphyseal region of the mandible, where the line of section for a hemi-mandibulectomy was originally done. 1 lesion recurred in the body of the mandible following a local excision as p r i m a r y treatment, and the remaining 3 growths recurred in the temporal fossa to produce widespread destruction in the course of growth. The full thickness resection line was in all instances placed approximately 10-12 m m anterior to where the radiological examination signified the existence of growth. To achieve a similar safe distance posterior to the lesion was not always possible particularly when some of the larger lesions were seen on the radiological examination to be closely approaching the condylar and coronoid processes. W h e n very close to the condylar head the mandible was disarticulated on the involved side. The condylar remnant was retained when it appeared that a satisfactory margin of unaffected bone was still present. The management of the lesions was governed by the site of presentation of the recurrence. A l l the patients had x - r a y s taken of their lungs and in none was there any evidence of the ameloblastoma having metastasized to the lungs.
2
I. Smith
Fig. 1 a + b Case 1 a) A full face photograph of case 1 illustrating recurrence of ameloblastoma in the left body of the mandible. b) The oral view of case 1 to show the expanding lesion which has extended to the left angle of the mandible.
Fig. 1 a
Fig. 1 b
Case 1
Case 4
This patient, a 16-year-old female, presented with a recurrence in the symphyseal stump (Figs. l a and b). The recurrence had extended to the left angle of the mandible. At 12 years of age a massive tumour of the right side of the mandible was removed by resection of that half of the jaw. The radiograph of the original lesion is seen in Fig. 8. The recurrent growth was removed by a further mandibular resection.
The patient, a female, 44 years of age, presented with an extensive mass of the right half of the mandible. This recurrence had taken approximately 2 years to reach it's present size. At the age of 24 years the patient presented with a growth involving the right body of the mandible, and from the hospital records, a local enucleation with burring away of a few mm of bone was the method of treatment in that instance. The radiograph of the recurrent lesion is seen in Fig. 4, and this demonstrates the amount of bony involvement and the multilocular pattern of the tumour.
Case 2 A female patient, 35 years of age, was treated in our department for a recurrent growth which had developed in the symphyseal stump of the mandible. The original hemi-mandibulectomy was carried out when the patient was 25 years old. The radiograph of this recurrence is illustrated in Fig. 2. The recurrent growth was removed by a further resection of the mandible. Case 3 This patient, a 43-year-old female, presented with a recurrent growth which was now contained in the bed of the resected left half of the lower jaw. Primary treatment which involved a left hemi-mandibulectomy and immediate bone grafting into the defect, was carried out when the patient was 33 years old. The radiograph seen in Fig. 3 demonstrates the recurrent lesion extending backwards and upwards from the symphyseal region of the mandible, as well as the invasion of the bone graft by tumor tissue. The recurrent growth was excised by a further mandibular resection.
The recurrent lesion was now removed by means of a resection of the right half of the mandible. Case 5 A female patient, 34 years of age, presented with a massive recurrent ameloblastoma of the left side of face (Figs. 5 a and b). By it's growth the lesion extended upwards into the temporal fossa, outwards into the soft tissues of the cheek and inwards into the oral cavity. As a result of the inward growth the left side of the maxilla was displaced almost towards the midline of the mouth. Deglutition and respiration were nevertheless unaffected. The original resective surgery was done when the patient was 24 years of age. As a significant part of the lesion was centred in the temporal region, the surgical approach for the removal of the recurrence was by means of a Ferguson Moore type incision which was extended upwards into the scalp to follow the upper tempo-
Recurrent Ameloblastoma of the Mandible
Fig. 2 The radiograph of case 2 illustrating a recurrence in the mandibular stump. Small Ioculation in the bone in advance of the obvious mass is evident.
3
Fig.£ A lateral oblique radiograph of case 3. The lesion is predominantly situated in the soft tissues and invasion of the replacement bone graft is clearly evident.
ral line of the skull. The resultant face splitting flap which was produced, permitted free access to the growth especially where it was situated in the temporal fossa. A post operative view of the patient is seen in Fig. 5 c. Case 6 This patient, a female, 37 years of age, presented with an enormous recurrent ameloblastoma which by it's upwards extension produced widespread destruction in the temporal fossa (Figs. 6 a and b). Treatment tor the primary growth was done when the patient was 27 years old. A total resection was then performed. The surgical approach used for the removal of the recurrence was similar to that described for the treatment of case 5. Case 7 This 70-year-old male patient presented with a recurrent amelobtastoma which was essentially situated in the temporal fossa region (Fig. 7). The patient was treated for the original growth by total resection at the age of 61 years. Treatment for the recurrence followed the lines of that used in the treatment of cases 5 and 6.
Discussion and Conclusion From the investigation of the recurrent lesions it is apparent that the excisions were inadequate even
Fig. 4 The lateral oblique radiograph of case 4. The multiocular pattern of the growth is clearly seen as is the presence of tumour tissue in the adjacent tissues.
though they were considered to be sufficiently wide. Certain aspects of the behaviour of these growths and the methods of primary surgery were explored in the hope that some explanation could be found for the recurrence of the Iesion. From this study a number of important facts have emerged. Firstly because of the varying clinical and radiological pattern with which these lesions present, it is vital that a diagnosis be made before any detlni-
4
1. Smith
Fig. 5 a
Fig. 5 b
Fig. 5 c
Fig. 5 a-c Case 5. a) A full face photograph of case 5. This recurrent lesion has reached enormous proportions and has infiltrated the left side of the face and the temporal region, b) A profile view of case 5. c) A photograph of case 5 taken a few months post-operatively. i!f!i~i!!
Fig. 6 a + b Case 6. a) This photograph is of case 6 in the text and illustrates a recurrent lesion which has widely infiltrated the face and temporal region. b) A profile view of case 6. Fig. 6 a
Fig. 6 b
Fig. 7 A photograph of case 7 illustrating a recurrent ameloblastoma involving the temporal fossa.
tive surgery is undertaken. Treatment should then consider both the curative and reconstructive aspects of surgery for these are directly linked, but the excision should not be sacrificed at the expense of the repair. The best hope for successful treatment is only possible if the diagnosis is known. Secondly it appears that with regards to the age of the patient, the only significant factor is the speed with which the lesion grows. StatisticaIly the lesion appeared to grow more rapidly in the young patient as one would expect when a lesion is developing in a growing bone. This was certainly the case with the 12-year-old child who had the primary surgery done in my unit and who within 4 years returned with an extensive recurrence. It is noteworthy that the ages of the other six patients
Recurrent Ameloblastoma of the Mandible
5
Fig, 8 An oblique radiograph illustrating primary ameloblastoma of the mandible in a 12-year-old female patient (case 1 in text), This demonstrates the rapidly growing turnout producing widespread destruction of bone,
Fig, 9 A radiographic view of a primary ameloblastoma of the mandible showing in this case a marked trabecular and multilocular appearance, The lower border of the mandible is intact at this stage in the development of the growth,
Fig, 10a
Fig, 10b
Fig, 10a+ b Sclerotic. appearance of ameloblastoma, a) A P,A. radiograph of a patient with primary ameloblastoma of the mandible. There is almost total involvement of the mandible, The sclerotic appearance of this lesion is suggestive of fibro-osseous disease of bone, b) A lateral oblique radiograph of the same patient showing the intense bone reaction to the growing tumour,
6
l. Smith
Fig. 11 An orthopantograph showing a malignant variety of ameloblastoma of the mandible. This demonstrates widespread bone destruction without reaction.
demonstrate massive expansion of bone with large cystic areas (Fig. 8), whereas to those where there has been a good body or bony response a marked trabecular or small locular pattern is usually noted (Fig. 9). When a bony response is most intense a radiological suggestion of fibro-osseous disease may be evident (Figs. 10 a and b). These facts support the view that one should take more care with those lesions to which the body response is poor, when treating the condition. When dealing with the malignant variety of ameloblastoma of the mandible, seen in Fig. l l , there is no question of avoiding a wide excision of the growth despite the serious disfigurement which results, and which one always hopes to avoid in different circumstances. Fig. 12 An oblique radiograph of primary ameloblastoma of the mandible. There is extensive involvement of the mandible but the condylar and coronoid remnants are still intact. A dentigerous cyst which is unrelated to this condition is present in the symphysis of the mandible,
with the recurrent growths were as follows: 34 years, 35 years, 37 years, 44 years and 70 years of age. These were the ages of the patients when they presented for further treatment. Another important fact is the type of clinical presentation of the growth. Although macroscopically the tumour tissue is more often found to be predominantly cystic and only occasionally solid throughout, body response to the growing lesion is variable, and this accounts for the varying clinical presentation and radiological patterns that are seen. Those lesions to which there has been a poor response are radiologically more destructive and
It is obvious that the extent of the lesion will depend on the duration of growth and because the size of the lesion will influence the method of management, it will require some consideration when treatment is being planned. Even though it is an accepted fact that treatment must be adequate which in the majority of circumstances would probably amount to radical surgery with it's consequent disfigurement, a degree of conservation can be taken with the smaller lesions, in which case a local excision, with the preservation of the lower border of the mandible would suffice. As the tumour tissue does not invade the Haversian system of the compact bone, the lower border can be preserved if it is not completely eroded (Kramer 1963). For the larger lesions and particularly with those that have eireumferentially destroyed the mandible there is no question of preserving the continuity of the bone, and radical surgery will be necessary. If these large lesions are situated in the symphysis of the mandible, they can in certain
Recurrent Ameloblastoma of the Mandible circumstances be removed by the 2 stage procedure which I have described in a previous publication (Smith 1968), where a strut of the lower border is retained as a spacer at the first operation and at a subsequent operation is replaced with a bone graft, for with this method the severity of the deformity and the associated disability which results from radical surgery in ~his region of the mandible, can be minimised. The bone cut being always far away from the lesion I would assume that a recurrence is due to the presence of infiltrated microscopic growth in the bone beyond the 10 mm mark where the resection was done, even though this is not apparent in both the clinical and radiotogical evidence. Alternatively one may postulate that the lesion could be multicentric in character. This could be supported by the fact that in all but one case 10 or more years elapsed before the lesion became active again. Finally the site of the primary lesion is important, and this is significant from two aspects. Firstly, with regards to the method of management of a primary growth and secondly, in anticipation of an inadequate primary excision leading to a recurrence of the growth. If the lesion recurs, and it is situated in the body or in the symphyseal region of the mandible,
further treatment for the removal of the growth is less involved, for there are few important surrounding structures which become directly involved in the growth. However when the recurrence is sited in the region of the ascending ramus of the mandible, it usually implicates important surrounding structures and by it's extension into the temporal fossa region produces a far more serious situation for the patient. Because of this, exceptional care must be taken in the temporal region, and it is important to give special consideration to the line of section of bone in the ascending ramus of the mandible, or to the value of preserving a small piece of condylar or coronoid process of the mandible when the primary procedure is being done (Fig. 12). Conclusion' To be hesitant or ultra conservative at the primary operation could result in a disasterous situation which could have been easily avoided with proper care in the first instance. Acknowledgements My thanks are due to Dr. ]. McMurdo, Superintendent of the Johannesburg General Hospital, and to Dr. J de W. Becker, Superintendent of WENELA Hospital for permission to publish and to the Photographic department of the Department of Surgery, Medical School for providing the photographic prints.
References
Kramer, 1. R. H.: Ameloblastoma. A Clinico-pathological appraisal. Brit. J. Oral Surg. 1 (1963) 13 Smith, I.: The Management of Ameloblastoma of the Mandible: A review on the treatment of 32 cases. S. Aft. reed. J. 42 (1968) 655
7
Dr. lan Smith, B.D,S. (Wits.), L.R.C.P., L.R.C.S. (Ire.), F.D.S.R.C.S. (Eng.), 103, Lancet Hall, ]eppe Street, Johannesburg, 2001, Transvaal, Republic of South Africa
Recurrent Ameleblastoma of the Mandible* Ian Smith Department of Maxillo-Facial and Oral Surgery (Head: I. Smith, B.D.S., L.R.C.P., L.R.C.S., F.D.S.R.C.S.) Johannesburg General Hospital and Univ. of the Witwatersrand, S. Africa
Summary Amelobtastoma is by nature an invasive tumour and the full extent of the infiltration is not always appreciated when the lesion is being excised. Included in a series of 40 cases are 7 recurrent lesions. Pertinent clinical features of the 7 recurrent cases are discussed. A close study has been made of the recurrent tumours in the hope that some explanation could be found for the unsuccessful primary treatment. The investigation considered a number of aspects of the behavior of this growth and from this certain facts have emerged. Definitive treatment should not be embarked on before the diagnosis has been established. Only then can an overall plan of management be devised. It is noteworthy that the rate of growth of the lesion is more rapid in the younger age group. Ameloblastoma varies in it's clinical and radiological presentation. Primary treatment is influenced by the size and site of the particular lesion. The management of the recurrent lesion depends on the anode of presentation of the particular growth.
Key-Words: Ameloblastoma of mandible; Recurrency. Introduction Ameloblastoma is by nature an invasive tumour and unfortunately the full extent of the infiltration is not always appreciated at the time of treatment, even though the clinical and radiological examinations have been thorough. In spite of what could appear to the surgeon to be an adequate excision, the occasion will arise when microscopic remnants of the growth will be missed, and it is from these loci that the tumour will continue to grow. From a series of 40 cases that have had treatment in our department it is possible to d r a w some conclusions as to the behavior of this growth and to make further comments about the management of this condition. Included in this series of 40 cases are 7 recurrent lesions. Of these, 6 patients had p r i m a r y treatment "* Paper read at I.A.D.R. Congress, Cape Town, Oct. 1974. 1 ], max.-fac.Surg. 1/76
elsewhere, while the remaining one received the initial treatment in our department. 5 lesions took an average of 10 years to r e a p p e a r as significant growths. 1 took 20 years to recur after what was described from the records to have been a local excision as the p r i m a r y method of treatment. The 7th. patient, who was first treated in our unit, returned with an extensive recurrence of the growth within 4 years of the initial treatment.
Clinical Material The mode of presentation of the 7 recurrent lesions was dependent on the site of origin of the recurrence. 3 lesions recurred in the stump in the symphyseal region of the mandible, where the line of section for a hemi-mandibulectomy was originally done. 1 lesion recurred in the body of the mandible following a local excision as p r i m a r y treatment, and the remaining 3 growths recurred in the temporal fossa to produce widespread destruction in the course of growth. The full thickness resection line was in all instances placed approximately 10-12 m m anterior to where the radiological examination signified the existence of growth. To achieve a similar safe distance posterior to the lesion was not always possible particularly when some of the larger lesions were seen on the radiological examination to be closely approaching the condylar and coronoid processes. W h e n very close to the condylar head the mandible was disarticulated on the involved side. The condylar remnant was retained when it appeared that a satisfactory margin of unaffected bone was still present. The management of the lesions was governed by the site of presentation of the recurrence. A l l the patients had x - r a y s taken of their lungs and in none was there any evidence of the ameloblastoma having metastasized to the lungs.
2
I. Smith
Fig. 1 a + b Case 1 a) A full face photograph of case 1 illustrating recurrence of ameloblastoma in the left body of the mandible. b) The oral view of case 1 to show the expanding lesion which has extended to the left angle of the mandible.
Fig. 1 a
Fig. 1 b
Case 1
Case 4
This patient, a 16-year-old female, presented with a recurrence in the symphyseal stump (Figs. l a and b). The recurrence had extended to the left angle of the mandible. At 12 years of age a massive tumour of the right side of the mandible was removed by resection of that half of the jaw. The radiograph of the original lesion is seen in Fig. 8. The recurrent growth was removed by a further mandibular resection.
The patient, a female, 44 years of age, presented with an extensive mass of the right half of the mandible. This recurrence had taken approximately 2 years to reach it's present size. At the age of 24 years the patient presented with a growth involving the right body of the mandible, and from the hospital records, a local enucleation with burring away of a few mm of bone was the method of treatment in that instance. The radiograph of the recurrent lesion is seen in Fig. 4, and this demonstrates the amount of bony involvement and the multilocular pattern of the tumour.
Case 2 A female patient, 35 years of age, was treated in our department for a recurrent growth which had developed in the symphyseal stump of the mandible. The original hemi-mandibulectomy was carried out when the patient was 25 years old. The radiograph of this recurrence is illustrated in Fig. 2. The recurrent growth was removed by a further resection of the mandible. Case 3 This patient, a 43-year-old female, presented with a recurrent growth which was now contained in the bed of the resected left half of the lower jaw. Primary treatment which involved a left hemi-mandibulectomy and immediate bone grafting into the defect, was carried out when the patient was 33 years old. The radiograph seen in Fig. 3 demonstrates the recurrent lesion extending backwards and upwards from the symphyseal region of the mandible, as well as the invasion of the bone graft by tumor tissue. The recurrent growth was excised by a further mandibular resection.
The recurrent lesion was now removed by means of a resection of the right half of the mandible. Case 5 A female patient, 34 years of age, presented with a massive recurrent ameloblastoma of the left side of face (Figs. 5 a and b). By it's growth the lesion extended upwards into the temporal fossa, outwards into the soft tissues of the cheek and inwards into the oral cavity. As a result of the inward growth the left side of the maxilla was displaced almost towards the midline of the mouth. Deglutition and respiration were nevertheless unaffected. The original resective surgery was done when the patient was 24 years of age. As a significant part of the lesion was centred in the temporal region, the surgical approach for the removal of the recurrence was by means of a Ferguson Moore type incision which was extended upwards into the scalp to follow the upper tempo-
Recurrent Ameloblastoma of the Mandible
Fig. 2 The radiograph of case 2 illustrating a recurrence in the mandibular stump. Small Ioculation in the bone in advance of the obvious mass is evident.
3
Fig.£ A lateral oblique radiograph of case 3. The lesion is predominantly situated in the soft tissues and invasion of the replacement bone graft is clearly evident.
ral line of the skull. The resultant face splitting flap which was produced, permitted free access to the growth especially where it was situated in the temporal fossa. A post operative view of the patient is seen in Fig. 5 c. Case 6 This patient, a female, 37 years of age, presented with an enormous recurrent ameloblastoma which by it's upwards extension produced widespread destruction in the temporal fossa (Figs. 6 a and b). Treatment tor the primary growth was done when the patient was 27 years old. A total resection was then performed. The surgical approach used for the removal of the recurrence was similar to that described for the treatment of case 5. Case 7 This 70-year-old male patient presented with a recurrent amelobtastoma which was essentially situated in the temporal fossa region (Fig. 7). The patient was treated for the original growth by total resection at the age of 61 years. Treatment for the recurrence followed the lines of that used in the treatment of cases 5 and 6.
Discussion and Conclusion From the investigation of the recurrent lesions it is apparent that the excisions were inadequate even
Fig. 4 The lateral oblique radiograph of case 4. The multiocular pattern of the growth is clearly seen as is the presence of tumour tissue in the adjacent tissues.
though they were considered to be sufficiently wide. Certain aspects of the behaviour of these growths and the methods of primary surgery were explored in the hope that some explanation could be found for the recurrence of the Iesion. From this study a number of important facts have emerged. Firstly because of the varying clinical and radiological pattern with which these lesions present, it is vital that a diagnosis be made before any detlni-
4
1. Smith
Fig. 5 a
Fig. 5 b
Fig. 5 c
Fig. 5 a-c Case 5. a) A full face photograph of case 5. This recurrent lesion has reached enormous proportions and has infiltrated the left side of the face and the temporal region, b) A profile view of case 5. c) A photograph of case 5 taken a few months post-operatively. i!f!i~i!!
Fig. 6 a + b Case 6. a) This photograph is of case 6 in the text and illustrates a recurrent lesion which has widely infiltrated the face and temporal region. b) A profile view of case 6. Fig. 6 a
Fig. 6 b
Fig. 7 A photograph of case 7 illustrating a recurrent ameloblastoma involving the temporal fossa.
tive surgery is undertaken. Treatment should then consider both the curative and reconstructive aspects of surgery for these are directly linked, but the excision should not be sacrificed at the expense of the repair. The best hope for successful treatment is only possible if the diagnosis is known. Secondly it appears that with regards to the age of the patient, the only significant factor is the speed with which the lesion grows. StatisticaIly the lesion appeared to grow more rapidly in the young patient as one would expect when a lesion is developing in a growing bone. This was certainly the case with the 12-year-old child who had the primary surgery done in my unit and who within 4 years returned with an extensive recurrence. It is noteworthy that the ages of the other six patients
Recurrent Ameloblastoma of the Mandible
5
Fig, 8 An oblique radiograph illustrating primary ameloblastoma of the mandible in a 12-year-old female patient (case 1 in text), This demonstrates the rapidly growing turnout producing widespread destruction of bone,
Fig, 9 A radiographic view of a primary ameloblastoma of the mandible showing in this case a marked trabecular and multilocular appearance, The lower border of the mandible is intact at this stage in the development of the growth,
Fig, 10a
Fig, 10b
Fig, 10a+ b Sclerotic. appearance of ameloblastoma, a) A P,A. radiograph of a patient with primary ameloblastoma of the mandible. There is almost total involvement of the mandible, The sclerotic appearance of this lesion is suggestive of fibro-osseous disease of bone, b) A lateral oblique radiograph of the same patient showing the intense bone reaction to the growing tumour,
6
l. Smith
Fig. 11 An orthopantograph showing a malignant variety of ameloblastoma of the mandible. This demonstrates widespread bone destruction without reaction.
demonstrate massive expansion of bone with large cystic areas (Fig. 8), whereas to those where there has been a good body or bony response a marked trabecular or small locular pattern is usually noted (Fig. 9). When a bony response is most intense a radiological suggestion of fibro-osseous disease may be evident (Figs. 10 a and b). These facts support the view that one should take more care with those lesions to which the body response is poor, when treating the condition. When dealing with the malignant variety of ameloblastoma of the mandible, seen in Fig. l l , there is no question of avoiding a wide excision of the growth despite the serious disfigurement which results, and which one always hopes to avoid in different circumstances. Fig. 12 An oblique radiograph of primary ameloblastoma of the mandible. There is extensive involvement of the mandible but the condylar and coronoid remnants are still intact. A dentigerous cyst which is unrelated to this condition is present in the symphysis of the mandible,
with the recurrent growths were as follows: 34 years, 35 years, 37 years, 44 years and 70 years of age. These were the ages of the patients when they presented for further treatment. Another important fact is the type of clinical presentation of the growth. Although macroscopically the tumour tissue is more often found to be predominantly cystic and only occasionally solid throughout, body response to the growing lesion is variable, and this accounts for the varying clinical presentation and radiological patterns that are seen. Those lesions to which there has been a poor response are radiologically more destructive and
It is obvious that the extent of the lesion will depend on the duration of growth and because the size of the lesion will influence the method of management, it will require some consideration when treatment is being planned. Even though it is an accepted fact that treatment must be adequate which in the majority of circumstances would probably amount to radical surgery with it's consequent disfigurement, a degree of conservation can be taken with the smaller lesions, in which case a local excision, with the preservation of the lower border of the mandible would suffice. As the tumour tissue does not invade the Haversian system of the compact bone, the lower border can be preserved if it is not completely eroded (Kramer 1963). For the larger lesions and particularly with those that have eireumferentially destroyed the mandible there is no question of preserving the continuity of the bone, and radical surgery will be necessary. If these large lesions are situated in the symphysis of the mandible, they can in certain
Recurrent Ameloblastoma of the Mandible circumstances be removed by the 2 stage procedure which I have described in a previous publication (Smith 1968), where a strut of the lower border is retained as a spacer at the first operation and at a subsequent operation is replaced with a bone graft, for with this method the severity of the deformity and the associated disability which results from radical surgery in ~his region of the mandible, can be minimised. The bone cut being always far away from the lesion I would assume that a recurrence is due to the presence of infiltrated microscopic growth in the bone beyond the 10 mm mark where the resection was done, even though this is not apparent in both the clinical and radiotogical evidence. Alternatively one may postulate that the lesion could be multicentric in character. This could be supported by the fact that in all but one case 10 or more years elapsed before the lesion became active again. Finally the site of the primary lesion is important, and this is significant from two aspects. Firstly, with regards to the method of management of a primary growth and secondly, in anticipation of an inadequate primary excision leading to a recurrence of the growth. If the lesion recurs, and it is situated in the body or in the symphyseal region of the mandible,
further treatment for the removal of the growth is less involved, for there are few important surrounding structures which become directly involved in the growth. However when the recurrence is sited in the region of the ascending ramus of the mandible, it usually implicates important surrounding structures and by it's extension into the temporal fossa region produces a far more serious situation for the patient. Because of this, exceptional care must be taken in the temporal region, and it is important to give special consideration to the line of section of bone in the ascending ramus of the mandible, or to the value of preserving a small piece of condylar or coronoid process of the mandible when the primary procedure is being done (Fig. 12). Conclusion' To be hesitant or ultra conservative at the primary operation could result in a disasterous situation which could have been easily avoided with proper care in the first instance. Acknowledgements My thanks are due to Dr. ]. McMurdo, Superintendent of the Johannesburg General Hospital, and to Dr. J de W. Becker, Superintendent of WENELA Hospital for permission to publish and to the Photographic department of the Department of Surgery, Medical School for providing the photographic prints.
References
Kramer, 1. R. H.: Ameloblastoma. A Clinico-pathological appraisal. Brit. J. Oral Surg. 1 (1963) 13 Smith, I.: The Management of Ameloblastoma of the Mandible: A review on the treatment of 32 cases. S. Aft. reed. J. 42 (1968) 655
7
Dr. lan Smith, B.D,S. (Wits.), L.R.C.P., L.R.C.S. (Ire.), F.D.S.R.C.S. (Eng.), 103, Lancet Hall, ]eppe Street, Johannesburg, 2001, Transvaal, Republic of South Africa