Department of Oral Pathology, Peking University School and Hospital of Stomatology, Beijing, PR China.
Research Unit of Precision Pathologic Diagnosis in Tumors of the Oral and Maxillofacial Regions, Chinese Academy of Medical Sciences (2019RU034), Beijing, PR China.
J Oral Pathol Med. 2022 Aug;51(7):659-665. doi: 10.1111/jop.13305. Epub 2022 Jun 7.
Orthokeratinized odontogenic cyst (OOC), a newly designated entity of odontogenic cysts, is an intraosseous jaw cyst that is entirely or predominantly lined by orthokeratinized squamous epithelium. The aim of this study was to report a large series of OOC to substantiate its clinicopathologic profiles and to investigate PTCH1 mutations in OOCs.
The clinicopathologic features of 167 OOCs from 159 patients were analyzed and the immunohistochemical expression of markers related to cell differentiation and proliferation was evaluated. Furthermore, PTCH1 mutations were analyzed in 14 fresh samples of OOC.
OOCs occurred mostly in the third and fourth decades (60.4%) with a male predilection (66.7%). The lesions developed more often in the mandible than maxilla, primarily in the posterior mandible and ramus. Eight patients (5.0%) showed multiple locations of either bilateral posterior mandible (n = 6) or both the maxilla and mandible. Radiographically, the majority of OOCs (91.2%) showed a well-demarcated, unilocular radiolucency with 14 multilocular cases (8.8%). A follow-up of 131 patients (123 treated by enucleation with or without marsupialization and eight by peripheral ostectomy) revealed no recurrence during an average period of 4.56 years after surgery. Immunohistochemistry indicated lower proliferative activity and a varying epithelial differentiation pattern in OOC compared with odontogenic keratocysts (OKC). No PTCH1 mutation was detected, except for three known single nucleotide polymorphisms.
The clinicopathological and molecular differences between OOC and OKC justified their separation, and unlike OKCs, OOCs did not harbor PTCH1 mutations, suggesting different pathogenesis underlying these two jaw cysts.
正角化牙源性囊肿（OOC）是牙源性囊肿的一种新的实体，是一种完全或主要由正角化鳞状上皮衬里的颌骨内囊肿。本研究的目的是报告一系列 OOC，以证实其临床病理特征，并研究 OOC 中的 PTCH1 突变。
分析了 159 例患者的 167 例 OOC 的临床病理特征，并评估了与细胞分化和增殖相关的标志物的免疫组织化学表达。此外，还分析了 14 例 OOC 新鲜样本中的 PTCH1 突变。
OOC 主要发生在第三和第四十年（60.4%），男性居多（66.7%）。病变多发生在下颌骨，上颌骨较少，主要发生在后下颌骨和下颌支。8 例（5.0%）患者出现双侧后下颌骨（n=6）或上颌骨和下颌骨的多处病变。放射学上，大多数 OOC（91.2%）表现为界限清楚的单房透光性，14 例为多房性（8.8%）。对 131 例患者（123 例采用切除加或不加袋形术治疗，8 例采用外周骨切除术治疗）进行了随访，平均随访 4.56 年后未见复发。与牙源性角化囊肿（OKC）相比，OOC 的免疫组织化学显示增殖活性较低，上皮分化模式不同。除了三个已知的单核苷酸多态性外，未检测到 PTCH1 突变。
OOC 和 OKC 的临床病理和分子差异证明了它们的分离，与 OKC 不同，OOC 不携带 PTCH1 突变，提示这两种颌骨囊肿的发病机制不同。
