CASO CLÍNICO

 

Pindborg tumor (Calcifying epithelial odontogenic tumor)

Tumor de Pindborg (tumor odontogénico epitelial calcificante)

 

 

J. Rubio Palau¹, C. Bescós Atín², J. Pamias Romero², M. Sáez Barba², G. Raspall Martín³, P. Huguet Redecilla⁴

1 Médico Residente.
2 Médico Adjunto.
3 Jefe de Servicio. Servicio de Cirugía Oral y Maxilofacial.
4 Médico Adjunto. Servicio de Anatomía Patológica.
Servicio de Cirugía Oral y Maxilofacial. Hospital Universitari Vall d´Hebron. Barcelona, España.

Correspondence

 

 

---

ABSTRACT

The aim of this article is to review the literature on Pindborg tumor based on a case. In view of its low frequency and the importance of histology for its correct diagnosis and treatment as it can be confused with other benign tumors, appropriate resection is necessary with tumor-free margins in order to reduce the probability of local recurrence.

Key words: Pindborg tumor; Calcifying epithelial odontogenic tumor.

---

RESUMEN

El objetivo del presente artículo es realizar una revisión de la literatura del tumor de Pindborg a propósito de un caso. El interés radica en su baja frecuencia y a la importancia de la anatomía patológica para su diagnóstico y correcto tratamiento ya que puede confundirse en algunos casos con otras tumoraciones benignas, a diferencia de las cuales, en este tumor debe realizarse una resección con márgenes de seguridad para disminuir la probabilidad de recidiva.

Palabras clave: Tumor de Pindborg; Tumor odontogénico epitelial calcificante.

---

 

Introduction

Pindborg tumor, also called Calcifying Epithelial Odontogenic Tumor (CEOT) is an uncommon, benign neoplasm with an invasive local nature. It tends to arise in the mandible and to recur. CEOT is a rare neoplasm that represents between 0.17 and 1.8% of all odontogenic tumors,¹ and only 200 cases have been published, with an average of 4 new cases per year in the world.²

Two varieties have been described according to their location: intraosseous or central (94% of cases) and extraosseous, peripheral or of soft tissues (6% of cases).² There is currently no consensus as to the origins of the tumor, and it is believed that it is derived from epithelial elements of the enamel organ, although other authors believe that it is derived from cellular remains of the basal lamina or from the basal layer of gingival epithelium.³

Mandibular involvement is commonly twice that of the maxilla, and it tends to arise in the premolar-molar area⁴ although a predilection has been described for the maxilla in orientals.¹ It is commonly associated with unerupted teeth, especially mandibular molars (52%) and odontogenic cysts.^4,5 Bimaxillary and bilateral involvement has also been described.³

There is no sex predilection in the central variety and more than two thirds of the lesions appear between the third and fifth decades in life.² The mean age is 40.3 years for central tumors and 31.8 for peripheral ones.⁴

 

Case Report

The patient was a 38 year old male that attended the Department of Oral and Maxillofacial Surgery of the Hospital Universitari Vall d´Hebron, having been referred by another center because of a tumor-like mass in the mandible that had been evolving for a year. (Fig. 1) His medical history included an ex-addiction to parenteral drug use. He was HCV and HIV positive and undergoing antiretroviral therapy. On examination a right-sided mandibular tumor-like mass could be appreciated that measured 5 cms, which was attached and hard in consistency.

The oral mucosa was intact. The orthopantomography showed a mixed lesion with calcifications in its interior that was affecting the right side of the mandible. (Fig. 2). The CAT scan showed an expansive mixed lesion in the right mandibular body that was destroying cortical bone, which measured 4.5x3x3.3 cm. (Fig. 3). The biopsy carried out reported a calcifying epithelial odontogenic tumor. The patient underwent a mandibulectomy of the right half which was reconstructed microsurgically with fibula. (Figs. 4 y 5). The anatomic pathology report described a mass measuring 4x2.5 cm with an irregular surface and a heterogeneous appearance, congestive areas and remains of teeth. This confirmed the diagnosis of calcifying epithelial odontogenic tumor of the mandible that was infiltrating the soft tissue of the periosteum. The mental nerve showed no invasion, and the intraoperative biopsy of the left facial system lymph node showed no signs of metastasis (Figs. 6 y 7).

The postoperative period was favorable and he was discharged able to tolerate food. His wounds were checked on an outpatient basis (Figs. 8, 9 y 10).

 

Discussion

Clinically these types of tumors are typically asymptomatic at diagnosis, and although they grow slowly, the tumor can have mechanical effects. In spite of being a benign neoplasm, it can be locally invasive.³ The tumor grows by means of infiltration and there can be expansion of the cortical bone, dental movement and root resorption. In some cases there may be pain, nasal obstruction, epistaxis, headaches and even bleeding.³ In the maxilla the sinuses may be affected. The recurrence rate is between 10 and 14%.^1,4

The extraosseous type tends to be located in the anterior gingiva presenting as a painless mass similar to an epulis.² There is no involvement of the jaw although the adjacent bone tends to show superficial erosion. Its behavior is less aggressive than the central variety, which permits more conservative treatment.⁴

The diagnosis tends to arise after routine radiography and, given its potentially invasive nature, a CAT scan should be carried out in order to determine its extension and treatment.^3,4

Radiologically the tumor has different stages of development. Initially the tumor is radiolucent, like an odontogenic cyst (especially when it is by an unerupted tooth) or like a cystic ameloblastoma. A mixed pattern will then follow, although some larger tumors may remain radiolucent4 and intralesional calcifications will appear.³ Finally, an irregular pattern will be displayed, with uni- or multilocular areas, like a honeycomb, due to destruction and tumor calcifications.^2,3 The tumor tends to be well-circumscribed radiologically in spite of having sclerotic margins that may not be visible.² The peripheral tumors tend to be radiolucent although the adjacent bone tends to have superficial erosion.⁴

The CAT scan is useful for showing calcification, unerupted teeth and bone erosion.¹ It will reveal a well-defined multilocular lesion expanding the bone, together with thinning of the cortical layer, bony septum, radio-opacity and unerupted teeth, although in this case an infiltrative type of lesion was shown given its advanced stage. Magnetic resonance will show a hyperintense lesion on T2 weighted sequences and hypointense on T1. These characteristics distinguish the tumor from other neoplasms that are more aggressive.⁴ RMI has the advantage of not using ionizing radiation and soft tissue is better defined.

The more changeable aspect of this tumor is its histology. The characteristic criteria for diagnosing it are large polygonal epithelial cells with welldefined borders and intercellular bridges.² The cytoplasm is abundant and eosinophilic. There is often cellular pleomorphism and the nuclei tend to be prominent and with a great variety of sizes, shapes and numbers. Mitosis tends not to be seen. At an extracellular level there tends to be accumulation of an amyloid type of material with birefringence of an apple-green color under polarized light after Congo red staining.⁴ A very important finding is concentric calcification in the amyloid material that will form Liesegang rings, which are pathognomonic for this tumor.² This calcified amyloid material stimulates the tumor stroma which leads it to segregate a collagenous matrix which will calcify.³

Different varieties of CEOT have been described: clear cell (which tends to be more aggressive and that has a greater recurrence rate),² Langerhan´s cell, myoepithelial cell or cementum-forming.

The differential diagnosis should include ameloblastoma, myxoma, aneurismatic bone cyst and odontogenic cysts, depending on the radiographs.⁴ Giant cell granuloma should also be ruled out, together with cemento-ossifying fibroma, ameloblastic fibro-odontoma and ameloblastic fibroma. If there is considerable bleeding the differential diagnosis should include central angioma of the mandible.³ If there are clear cells, the clear cell odontogenic carcinoma should also be considered together with clear cell ameloblastoma, intraosseous carcinoma, salivary gland neoplasms and aggressive osteoblastoma.⁵

The treatment is basically surgical and this should be tailored in each case according to the extension, location and characteristics of the patient. If conservative treatment is elected entailing enucleation, or curettage with a healthy tissue margin, together with a prolonged follow-up, the recurrence rate of 15-30% over 2-4 years should be taken into account.⁴ Therefore, due to its infiltrative nature, a clinical and radiological resection with a one centimeter margin of healthy tissue is preferable (0.5 for peripheral tumors as they are less aggressive) and a recurrence-free outcome will in this way be achieved. In cases affecting the jaw, in other words the clear cell variety, a more aggressive approach should be taken.⁵ As a result the best treatment method is to include 1-1.5 cm margins together with a follow-up period of 5-10 years.⁴

 

Conclusions

Pindborg tumor is a rare benign lesion. Given its unpredictable behavior and its unspecific radiological findings, carrying out an anatomopathologic study is necessary, as is resective surgery in order to minimize the probability of recurrence. Also necessary is a postoperative follow-up of at least five years.

 

 

Correspondence:
Josep Rubio Palau
Paseo Vall d´Hebron, 119-129
08035 Barcelona, España
Email: jrubiopalau@yahoo.es

Recibido: 19.09.06
Aceptado: 18.12.06

 

References

1. Ching AS, Pak MW, Kew J, Metreweli C, CT and MR Imaging appearances of an Extraosseus Calcifying Epithelial Odontogenic Tumor (Pindnorg Tumor), Am J Neuroradiol 2000;21:343-5.        [ Links ]

2. Germanier Y, Bornstein MM, Stauffer E, Buser D, Calcifying epithelial odontogenic (Pindborg) tumor of the mandible with clear cell component treated by conservative surgery: report of a case. J Oral Maxilofaci Surg 2005;63:1377-82.        [ Links ]

3. Belmonte-Caro R, Torres-Lagares D, Mayorga-Jiménez F, García-Perla García A, Infante-Cossio P, Gutiérrez-Pérez JL, Calcifying epithelial odontogenic tumor (Pindborg tumor). Med Oral 2002;7:309-15.        [ Links ]

4. Patiño B, Fernández-Alba J, Garcia-Rozado A, Martin R, Lopez-Cedrún JL, Sanromán B, Calcifying epithelial odontogenic (pindborg) tumor: a series of 4 distinctive cases and a review of the literature. J Oral Maxilofac Surg 2005;63:1361- 8.        [ Links ]

5. Maiorano E, Renne G, Tradati N, Viale G. Cytogical features of calcifying epithelial odontogenic tumor (Pindborg tumor) with abundant cementum-like material, Virchows Arch 2003;442:107-10.        [ Links ]