颌骨造釉细胞瘤64例临床分析

本文对我院１９５４－１９９０年收治的６４例颌骨造釉细胞瘤进行了回顾性分析，未发现１例恶性。特别是我们在长期工作实践中发现肿瘤与周围正常骨质有较明显的分界。遂于１９６３年开始试行颌骨内种瘤出术，至１９９０年６月已经成功地施了１２例，１例因手术时肿物巨大而且合并感染于术后１０年复发外，其余１１例术后随访年６个月－２７年，中位１２年１０个月均无复发。发种手术损伤小，方法简单，无损美容，预后性，特别是对颌     

c-myc mRNA在成釉细胞瘤中的表达

目的:研究成釉细胞瘤(AB)和牙源性角化囊肿(OKC)中c-mycmRNA的表达,探讨c-myc在AB和OKC中的发生、发展及其生物学意义。方法:使用原位杂交法检测54例AB、16例OKC和7例口腔正常黏膜(NOM)组织中c-mycmRNA的表达,并将AB按原发、复发、恶变分组,结果使用χ2检验进行统计分析。结果:AB、OKC及NOM组织中c-mycmRNA的阳性表达率分别为81.5%(44/54)、75.0%(12/16)和14.3%(1/7),3组比较有显著性差异(χ2=15.488,P<0.05)。原发组AB中c-mycmRNA的阳性表达率为71.0%,复发组为94.7%,恶变组为100.0%,伴随原发、复发、恶变,差异有显著性(χ2=16.912,P﹤0.05)。结论:c-myc表达在AB的发生、发展中有重要作用;c-mycmRNA的表达与AB的临床生物学行为有关,伴随其生物学行为变化,c-mycmRNA表达增强;提示c-myc有可能成为评价预后的有效指标。     

Fine-needle aspiration biopsy of tibial adamantinoma: a case report

Adamantinoma of long bones is a rare, primary bone tumor of controversial histogenesis, usually arising in the anterior midshaft of the tibia. This slowly growing, radiolucent, expansile tumor eventually causes thinning or destruction of overlying cortical bone. Fine-needle aspiration biopsy (FNAB) is a rapid, safe, and relatively painless means of obtaining diagnostic material from bone tumors, provided the mass has eroded through or markedly attenuated the overlying cortex. A case is presented of primary adamantinoma of the tibia which was sampled first by FNAB and subsequently by surgical biopsy.     

The clinicopathologic relevance of RECK gene polymorphisms in ameloblastoma

ObjectiveTo investigate the relationship between RECK gene polymorphisms and the clinicopathologic features of ameloblastoma.DesignNormal gingival mucosa specimens were obtained from 10 healthy volunteers. Ameloblastomas were surgically removed from 30 patients and part of the tumor specimens were used to detect RECK gene polymorphisms by using PCR-single-strand conformation polymorphism (PCR-SSCP) and DNA sequencing analysis. Expression of RECK and MMP-9 protein was measured using western blot.ResultsThe overall SNP rate was 46.7% (14/30). Four polymorphisms were detected in exon 9, 11, 13, 15 of the RECK gene: two synonymous (P520P and R625R) and two missense SNPs (V275I and I395 V). RECK protein expression in specimens with minor RECK SNPs was lower than that in specimens without RECK SNPs (P < 0.05), and, RECK protein expression in specimens with and without RECK SNPs was lower than that in the normal gingiva specimens (P < 0.05). MMP-9 protein expression in specimens with minor RECK SNPs was higher than that in specimens without RECK SNPs (P < 0.05), and MMP-9 protein expression in specimens with and without RECK SNPs was higher than that in normal gingiva specimens (P < 0.05). RECK gene polymorphisms were closely associated with active proliferation, capsular invasion, and clinical recurrence of ameloblastoma.ConclusionThe rs16932912(G/A) SNP in the RECK gene was closely associated with active proliferation, capsular invasion, and clinical recurrence of ameloblastoma. RECK protein expression was closely associated with the presence of the rs16932912(G/A) SNP.     

COX-2 as a determinant of lower disease-free survival for patients affected by ameloblastoma

Ameloblastoma is a locally aggressive neoplasm with a poorly understood pathogenesis. Therefore, the aim of this study is to investigate whether COX-2 expression is associated with ameloblastoma microvascular density (MVD) and with tumor aggressiveness. Sixty-three cases of primary ameloblastomas arranged in tissue microarray were submitted to immunohistochemistry against cyclooxigenase-2 (COX-2) and CD34. Clinicopathological parameters regarding sex, age, tumour size, tumour duration, tumour location, treatment, recurrences, radiographic features, vestibular/lingual and basal cortical disruption and follow-up data were obtained from patients’ medical records and correlated with the proteins expression. The results on BRAF-V600E expression were obtained from our previous study and correlated with COX-2 and CD34 expressions. Log-rank univariate analysis and multivariate Cox regression model were done to investigate the prognostic potential of the molecular markers. Twenty-eight cases (44.4%) exhibited cytoplasmic positivity for COX-2, predominantly in the columnar peripheral cells, with a mean MVD of 2.2 vessels/mm². COX-2 was significantly associated with recurrences (p?<?0.001) and BRAF-V600E expression (p?<?0.001), whereas lower MVD was associated with the use of conservative therapy (p?=?0.004). Using univariate and multivariate analyses, COX-2 was significantly associated with a lower 5-year disease-free survival (DFS) rate (p?<?0.001 and p?=?0.012, respectively), but not with a higher MVD (p?=?0.68). In conclusion, COX-2 expression in ameloblastomas is not associated with MVD, but it is significantly associated with recurrences and with a lower DFS.     

Matrix Metalloproteinase-9 (MMP-9) Expression in Different Subtypes of Ameloblastoma

Background

Ameloblastoma is a common benign odontogenic tumor of the jaw with a local invasive and highly destructive behavior and can develop in any age, with peak prevalence in 3rd–4th decade. Ameloblastoma can be divided into six histological types: follicular, plexiform, acanthomatous, desmoplastic, granular, and basal cell. Matrix metalloproteinase-9 (MMP-9) (92-kD gelatinase/type IV collagenases = gelatinase B) is involved in bone resorption by degradation of extracellular matrix and osteoclasts recruitment. Recent studies have found that MMP-9 is expressed by ameloblastoma and has a role in ameloblastoma local invasiveness.

Objective

To analyze MMP-9 expression between different histological types of ameloblastoma.

Material and Method

Forty samples of ameloblastoma were collected through consecutive sampling and the MMP-9 expression was detected using immunohistochemistry.

Result

All samples showed positive MMP-9 expression with moderate to strong intensity. 82.4 % plexiform type and 83.3 % mixed type have strong immunoexpression, significantly different with follicular type with only 36.4 % (P < 0.05).

Conclusion

Ameloblastoma plexiform and mixed type have higher MMP-9 expression than ameloblastoma follicular type. Different MMP-9 expression may contribute in different ameloblastoma biological behavior.     

A technique of tongue fixation after total mandibulectomy: the Oji spatula

When ameloblastoma presents late, as is often the case in Nigeria, it can affect the whole mandible. The treatment of choice is total mandibulectomy. The procedure may necessitate the resection of the musculature of the floor of the mouth to which a large portion of the tongue is attached. In our hospitals, immediate reconstruction is not undertaken for various reasons. Consequently, the musculature of the floor of the mouth cannot be reattached to a graft. The purpose of this paper is to illustrate a simple and patient-friendly method for fixation of the tongue after total mandibulectomy to achieve a secure airway. The tongue is tied to a wooden spatula, which stretches horizontally across the mouth. It is in contrast to the conventional technique of rigid fixation of the tongue to the pectoral muscle. This technique was used for 11 patients with large ameloblastomas. For the purpose of comparison, the conventional technique was used in 4 patients. The method of using a wooden spatula as a means of tongue fixation is known in the maxillofacial unit of the University of Nigeria Teaching Hospital, Enugu as the Oji spatula after the surgeon who developed it. All 11 patients tolerated this method well, but the 4 patients who had their tongues tied to the pectoral muscle complained of pain and discomfort. All the patients survived the procedure without postoperative blockage of the airway by the tongue. Follow-up for up to 6 months established that the patients had no respiratory problems.     

Plexiform ameloblastoma presenting as a sinonasal tumor

Ameloblastomas are the most frequent odontogenic tumours, accounting for 1% of all tumours of the maxilla and mandible. Sinonasal ameloblastomas are most common between the ages of 55 and 65, and mandibular ameloblastomas between 40 and 50. Incidence is higher in males than in females, and there are no differences between races. These locally aggressive tumours originate in the mandible in 80% of cases and in the maxilla in 15–20%. We report an unusual primary nasosinusal ameloblastoma presented in a 68-year-old male. The tumour was completely resected by (para)lateral rhinotomy and treated with postoperative radiotherapy. Histological analysis demonstrated a plexiform ameloblastoma. The patient remains well without disease after 50 months of postoperative follow-up.