PEDIATRIC/CRANIOFACIAL Craniomaxillofacial Fibrous Dysplasia: Conservative Treatment or Radical Surgery? A Retrospective Study on 68 Patients Valentino Valentini, M.D.S., Ph.D. Andrea Cassoni, M.D.S. Tito Matteo Marianetti, M.D. Valentina Terenzi, M.D. Maria Teresa Fadda, D.M.D., M.D.S. Giorgio Iannetti, M.D.S., Ph.D. Rome, Italy
Background: Fibrous dysplasia is a benign bone lesion characterized by replacement of normal bone with fibro-osseous connective tissue. The surgical treatment of fibrous dysplasia is based on one of two different approaches, conservative or radical. Methods: From January of 1980 to December of 2002, 95 patients with fibrous dysplasia located in the craniomaxillofacial area presented to the authors’ department. Twenty-one had the polyostotic type (22 percent), two had McCuneAlbright syndrome (2 percent), and 72 had the monostotic type (76 percent). Of 95 patients, 68 underwent surgery; the remaining 27 refused. Among the 68 patients who underwent surgery, 61 had radical excision, six received conservative treatment, and a patient with mandibular involvement received radical excision and immediate reconstruction with a free fibula flap after a recurrence experienced 2 years after primary remodeling surgery Results: No disease recurrence was observed in cases treated with complete excision, whereas a case of mandibular involvement treated with remodeling required further surgery. Infection, resolved with antibiotics, was seen in one case, and palatal fistula was seen in two cases. In one case with cranial base involvement liquorrhea was observed. Conclusions: In most cases of monostotic or monofocal fibrous dysplasia of the craniofacial region, modern surgical techniques allow an aggressive but definitive treatment with good functional and aesthetic results. The authors perform radical treatment even in cases involving the maxilla and mandible, and prefer a conservative approach only in polyostotic cases and McCune-Albright syndrome. (Plast. Reconstr. Surg. 123: 653, 2009.)
F
ibrous dysplasia is a benign bone lesion characterized by replacement of normal bone with fibro-osseous connective tissue.1 Von Recklinghausen,2 in 1891, was the first to describe a pathologic condition of the bone characterized by deformity and fibrotic changes, which he called “osteitis fibrosa generalisata”; in 1938, Lichtenstein and Jaffe3 first introduced the term “fibrous dysplasia.” They also noted that fibrous dysplasia can be monostotic or polyostotic. In 1937, McCune4 and Albright et al.5 recognized the relationship among the polyostotic form, precocious
From the Department of Maxillofacial Surgery, Policlinico “Umberto I,” University of Rome “La Sapienza.” Received for publication December 12, 2007; accepted August 20, 2008. Copyright ©2009 by the American Society of Plastic Surgeons DOI: 10.1097/PRS.0b013e318196bbbe
puberty, and areas of cutaneous pigmentation (cafe´ au lait spots), an association now known as McCune-Albright syndrome. Even though fibrous dysplasia may affect any bone in the body, craniofacial involvement occurs in 50 to 100 percent of patients. It involves most frequently, in descending order, the maxilla, mandible, frontal bones, sphenoidal bones, ethmoidal bones, parietal bones, temporal bones, and occipital bones.6 Maxillary lesions often involve adjacent bones (the zygomatic, sphenoid, nasal, or frontal bone), for which the term “monofocal” is more indicated, when several adjacent skeletal segments in a single area are affected.7
Disclosure: None of the authors has a financial interest to disclose in relation to the content of this article.
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Plastic and Reconstructive Surgery • February 2009 The etiology of the abnormal fibro-osseous process has been clarified only relatively recently. Marie et al.8 and Riminucci et al.9 showed that the development of fibrous dysplasia reflects a mutation that alters the function of osteogenic cells. Activating mutation of the Gs-a protein in osteoblastic cells is implicated in the development of the lesions. The substitution of cysteine or histidine with arginine in position 201 determines the loss of guanosine triphosphate activity with an increase of adenylate cyclase activity and consequent increase in the proliferation and inappropriate differentiation of cells, with excessive and disordered production of collagen. Yamamoto et al.10 investigated the role of interleukin-6 in the bone lesions of patients affected by McCune-Albright syndrome. They noted that cells cultured from these lesions show increased interleukin-6 secretion, which determines an increase in the number of osteoclasts. This may explain how pamidronate, a potent osteoclast inhibitor, can produce increases in the density of the lesions and delay the spread of the lesions into surrounding bones.11 Diagnosis of fibrous dysplasia is based on clinical, radiographic, and histological findings. Clinical examination can show an increase in the volume of bone affected, causing facial asymmetry. The signs and symptoms depend on the area involved. The most common clinical sign is swelling or deformity of the affected bone, but fibrous dysplasia can present with nasal obstruction, sinusitis, hearing loss, headache, dystopia, diplopia, dysesthesia, proptosis, and loss of vision.12 Radiological features can be cystic, sclerotic, or pagetoid, often with a typical “ground glass” appearance caused by the mixture of fibrous and osseous elements. The radiographic density of the lesions depends on the proportion of these elements.13 From a histological point of view, three main types have been identified: (1) the “Chinese letters” model, (2) the “pagetoid” model, and (3) the “hypercellular” model. Each of these is differentiated on the basis of the architecture and cellularity of the osseous tissue.9 The Chinese letters model is the most common. The bone trabeculae are thin and disconnected, with active osseous reabsorption by osteoclasts. The osteogenic cells are star-shaped and numerous Sharpey fibers are present. The pagetoid model is similar to the bone tissue found in Paget disease, with a dense and sclerotic trabecular tissue. The hypercellular model is characterized by the presence of discontinuous bone trabeculae distributed in an ordered and sometimes parallel fashion.9
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Therapy for fibrous dysplasia is surgical. Radiotherapy must be avoided, since it is ineffective and increases the incidence of malignant degeneration.14 Surgical treatment may range from conservative therapy (curettage, contouring, or remodeling), which may eventually be repeated, to radical excision followed by immediate reconstruction.1 To our knowledge, our series of patients is the one of the largest presented in the literature and can be useful for epidemiological purposes, as well as for considering how our management of fibrous dysplasia has been modified and improved with the evolution of surgical techniques.
PATIENTS AND METHODS From January of 1980 to December of 2002, 95 patients with fibrous dysplasia located in the craniomaxillofacial area presented to the Department of Maxillofacial Surgery of the University of Rome “La Sapienza.” The average patient age was 24.6 years (range, 4 to 52 years). Twenty-one patients had the polyostotic type (22 percent), two had McCune-Albright syndrome (2 percent), and 72 had the monostotic type (76 percent). (In this study, forms affecting two contiguous segments of bone were classified as monostotic, and thus “monostotic” should be understood as meaning “monofocal.”) The areas of involvement in these patients are listed in Table 1. Of 95 patients, 68 underwent surgery; the remaining 27 did not because of patient refusal. Among the 68 patients who underwent surgery, 61 had radical excision, six received conservative treatment, and a patient with mandibular involvement received radical excision and immediate reconstruction with a free fibula flap after a recurrence experienced 2 years after primary remodeling. Treatment procedures are listed in Table 2. The reconstruction after radical surgery was performed in all 62 patients operated on, except for 11 patients who had simple removal. Reconstruction was achieved with bone grafts in 21 patients (Figs. 1 through 8; donor sites: iliac crest in 14 patients, calvaria in three, and rib in four), alloplastic materials in three patients, and local and pedicled flaps in 21 patients; a fibula free flap was used to reconstruct the mandible and maxilla in three cases each.
RESULTS The patients were followed up with clinical examinations, radiographic films, computed tomography scanning, and vision examinations (Hess screen and visual evocated potentials in cases of orbital involvement) for 5 to 15 years (average, 7.6 years). All patients operated on
Volume 123, Number 2 • Craniomaxillofacial Fibrous Dysplasia Table 1. Fibrous Dysplasia: Involved Areas (total no. of patients ⴝ 95) Involved Area Mandible Maxillary bone Cheekbone Maxillary ⫹ cheekbone Ethmoid Sphenoid Frontal Temporal Parietal
Monostotic
Polyostotic
Total
19 23 2 13 5 2 2 1 0
2 6 0 3 10 12 8 8 2
21 29 2 16 15 14 10 9 2
between 1980 and 1991 received postoperative radiographs for postoperative and long-term follow-up control; since 1991, we have used computed tomography to follow our patients. In no patient treated with complete excision was disease recurrence observed, whereas a patient with mandibular involvement treated with remodeling required further surgery. In a patient treated with bone graft reconstruction, infection was observed and resolved with antibiotics; two patients with maxillary involvement required a subsequent operative intervention under local anesthesia to close a palatal fistula. Liquorrhea was observed in one patient with cranial base involvement, so reconstruction with a galea flap was performed. In the other patients, acceptable or good aesthetic and functional results were observed. All patients who underwent reconstruction with free flaps or bone grafts received adequate implant or prosthetic rehabilitation (Figs. 9 through 16). Optic nerve decompression was performed in four cases: three patients were symptomatic (visual loss, exophthalmus), whereas in one patient massive ethmoidal involvement led to a radical resection with decompression of the optic canal on his Table 2. Treatment Procedures Performed in Involved Areas (total no. of patients ⴝ 68) Surgical Procedure Excision and reconstruction
Conservative shaving
Optic nerve decompression
Involved Area
Total
Mandible Maxillary ⫹ cheekbone Ethmoid Sphenoid Frontal Temporal Parietal Mandible Maxillary ⫹ cheekbone Frontal McCune-Albright syndrome Temporal
17* 32 8 3 3 2 1 3* 3 1 1 1 4
*In one patient, primary remodeling and subsequent complete excision were performed because of disease recurrence.
medial side. In all cases, resolution of exophtalmus was observed. In a patient with previous amaurosis, visual recovery was not obtained, whereas in the other two symptomatic patients improved visual acuity (2 degrees) was observed.
DISCUSSION Fibrous dysplasia is a benign pathological bone disorder, but it can have a devastating outcome with high recurrence rates, especially after partial resections. Some authors1,15,16 report that the pathology does not progress after puberty; however, others13,17 have found that its progression is continuous, even during adulthood. The aim of the treatment of fibrous dysplasia is to correct or prevent functional problems and to achieve an aesthetic improvement. No medical treatment allows the arrest of the progression of the illness. Biphosphonates, which inhibit osteoclastic activity, can alleviate pain and improve the radiological appearance; steroids are currently used as a support therapy before and after surgical decompression of the optic nerve, but they cannot definitively halt the progression of the illness.12,14 The surgical treatment of fibrous dysplasia is based on two different approaches, conservative or radical. Conservative shaving or osseous contouring has been recommended by some authors18 who maintained that periodic contouring could be performed until a static phase was reached, even if continued growth was observed after conservative treatment. However, interventions have become more aggressive as advances have been made in surgical techniques19 and nowadays most authors13,14,17,19 are in favor of radical surgical therapy, which permits the complete removal of the lesion followed by immediate reconstruction. We adopted conservative techniques in only six old cases; in most cases, radical excision was performed, and according to advances in surgical techniques, in the last cases reconstruction with free flaps was performed. Chen and Noordhoff20 and Ricalde and Horswell12 divided the craniofacial skeleton into four zones on the basis of surgical, aesthetic, and functional considerations. They adopted conservative treatment for the alveolar part of the maxilla and mandible and for the cranial base, and the radical approach for the fronto-orbital area and the maxillozygomatic complex. Ozek et al.1 stated that orbital hypertelorism, dystopia, or proptosis can only be corrected by radical excision and reconstruction, but they prefer the conservative approach for the alveolar part of the maxilla and the mandible in an attempt to preserve alve-
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Plastic and Reconstructive Surgery • February 2009 has a positive psychological effect for the patient. In fact, no relapse has been observed in our patients who received radical excision with immediate reconstruction, whereas a patient who underwent remodeling of the displastic bone required further surgical treatment. Posnick7 also states that the treatment of choice should be radical as it allows for the complete resolution of the illness with immediate functional and aesthetic recovery. Furthermore, Kreutziger15 affirms that conservative treatment has no curative potential but only a palliative aesthetic aim and is unable to eliminate the lesions. Zenn and Zuniga,17 in considering the numerous relapses (25 to 50 percent) following
Fig. 1. Case 1. Preoperative frontal view of a patient with fibrous dysplasia involving the left maxilla and zygoma.
Fig. 3. Case 1. Preoperative computed tomography scan illustrating the maxillary and malar involvement.
Fig. 2. Case 1. Preoperative axial view.
olar ridges and tooth. In accordance with Posnick7, Kreutziger15 and Zenn and Zuniga,17 we perform radical treatment even in cases involving the maxilla and the mandible and use the conservative approach only in polyostotic cases and cases involving McCune-Albright syndrome. Iliac crest, rib, and calvaria grafts or revascularized free flaps allow immediate reconstruction of the surgical defect with good anatomical and functional recovery. In our experience, the radical approach prevents the occurrence of relapses and is the unique option for eliminating the illness; it also
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Fig. 4. Case 1. Intraoperative view of reconstruction of the inferior orbital margin with calvaria.
Volume 123, Number 2 • Craniomaxillofacial Fibrous Dysplasia which can be gradually revitalized by the invasion of normal bone. This procedure can maintain the original anatomy and eliminate donor-site morbidity derived from the grafting of large amounts of autogenous bone. Surgical reconstruction can be obtained with revascularized free flaps as well.22 In six of our patients, surgical reconstruction was performed with free fibula bone graft, with good functional and aesthetic results. Most authors today are in favor of radical excision and immediate reconstruction,7,12,15,17,20 but the most controversial points are the management of fibrous dysplasia involving alveolar bone and cases in which the optic nerve canal is involved, particularly in pa-
Fig. 5. Case 1. Postoperative frontal view.
Fig. 7. Case 1. Postoperative computed tomography scan (axial view).
Fig. 6. Case 1. Postoperative axial view.
conservative treatment, are in favor of radical treatment in mandibular fibrous dysplasia. Reconstruction after resection of the involved craniofacial bone is usually performed immediately.19 The goals are to prevent functional problems and to restore symmetry, volume, and contour. Some authors14,21 remove, thin, remodel, and reimplant fibrous dysplastic bone grafts for the reconstruction of surgical defects, with the aim of offering an excellent support for the migration of osteoblasts from surrounding normal bone. Other authors12,13 suggest reconstruction with reimplantation of resected bone after autoclaving,
Fig. 8. Case 1. Postoperative three-dimensional computed tomography scan showing the maxillary alveolar ridge reconstructed with an iliac crest bone graft and the inferior orbital margin with calvaria.
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Fig. 11. Case 2. Preoperative computed tomography scan showing maxillary involvement.
Fig. 9. Case 2. Preoperative frontal view of a patient with fibrous dysplasia involving the right maxilla.
observe the progression of the illness, but in cases of massive bone involvement or functional impairment, we prefer to perform surgery, trying to be as conservative as possible to prevent growth alteration. With regard to optic nerve decompression, some authors16 maintain that prophylactic decompression is necessary even in the absence of symptoms, taking into account the relative rapidity of vision deterioration when radiographic involvement of the nerve canal is present. However, other authors23 consider it better to observe the progression of the illness rather than perform an early prophylactic decompression, because of postop-
Fig. 10. Case 2. Preoperative intraoral view showing maxillary swelling.
tients with normal vision. Chen and Noordhoff 20 and Ricalde and Horswell12 adopted conservative treatment for the alveolar part of the maxilla and the mandible. We think there is no need to keep teeth and alveolar crests when involved with fibrous dysplasia, because we have excellent surgical possibilities for reconstructing alveolar bone with revascularized or free bone grafts and performing implant-prosthetic rehabilitation. We will never obtain the complete “restitutio ad integrum,� but the patient will be free from the illness. In growing patients, we usually prefer to wait and
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Fig. 12. Case 2. Intraoperative view of fixture positioning: reconstruction of the maxillary bone was performed with a doublebarred fibula free flap.
Volume 123, Number 2 • Craniomaxillofacial Fibrous Dysplasia
Fig. 15. Case 2. Postoperative computed tomography scan (axial view).
Fig. 13. Case 2. Postoperative frontal view.
involvement of the optic canal should be monitored very closely with regular ophthalmologic examinations, including visual evoked potentials, and that a therapeutic surgical decompression should be performed only when an initial impairment of vision is present. Besides in cases of optic nerve decompression, we prefer conservative treatment of fibrous dysplasia only in cases involving the cranial base, polyostotic forms, and McCune-Albright syndrome. On the other hand, we can conclude that modern surgical techniques allow, in the majority of cases of monostotic or monofocal fibrous dysplasia of the craniofacial region, an aggressive but definitive treatment with good functional and aesthetic results.
Fig. 14. Case 2. Postoperative intraoral view showing implantprosthetic rehabilitation.
erative risks and the lack of a close correlation between computed tomographic images and effective vision impairment. In fact, it has been demonstrated that despite restriction of the canal, 95 percent of patients have normal vision.23 Surgical decompression can cause loss of vision, with optic nerve traction, thermal damage, postoperative edema, and bleeding the main suspected causes. Some authors prefer to use steroid treatment in patients in whom the nerve canal is affected, even though real benefits are only obtained in a few cases and are limited in time.12 We think patients with radiological signs of initial
Fig. 16. Case 2. Postoperative three-dimensional computed tomography scan showing reconstruction of the maxillary bone with a double-barred fibula free flap.
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Plastic and Reconstructive Surgery • February 2009 Valentina Terenzi, M.D. Via Eugenio IV, no. 28 00167 Rome, Italy v.terenzi@libero.it
10.
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