BACKGROUND Orthokeratinized odontogenic cyst (OOC) is a benign odontogenic cyst. It is a variant of the common odontogenic keratocyst (OKC). This case report describes a rare malignant transformation of OOC, with the ...BACKGROUND Orthokeratinized odontogenic cyst (OOC) is a benign odontogenic cyst. It is a variant of the common odontogenic keratocyst (OKC). This case report describes a rare malignant transformation of OOC, with the aim of raising awareness of the malignant potential of OOC and distinguishing it from OKC. CASE SUMMARY In August 2018, a 52-year-old man was referred to the Department of Oral Maxillofacial and Head–Neck Oncology of Wuhan University. The patient presented with severe pain in the left mandible for 2 mo, and had a 5-year history of osteomyelitis and mandibular cyst with three recurrences. His latest diagnosis by pathological examination was OOC of the left mandible with mild-tomoderate local proliferation. However, the cyst showed malignant potential by radiographic examination. We performed partial mandibulectomy and sent the lesion tissue for pathological examination. As expected, the cyst had deteriorated to moderately differentiated squamous cell carcinoma. During postoperative follow-up, the patient went for chemotherapy in September 2018 and successfully completed four cycles. CONCLUSION Surgeons should be more aware of OOC, which is usually benign but can become malignant.展开更多
Background: With transitions in the disease concept of orthokeratinized odontogenic cyst (OOC), the pathogenesis and etiology have not been sufficiently elucidated. Objectives: OOC cases were reclassified and observed...Background: With transitions in the disease concept of orthokeratinized odontogenic cyst (OOC), the pathogenesis and etiology have not been sufficiently elucidated. Objectives: OOC cases were reclassified and observed to understand the clinico-histopathological characteristics. In addition, literature review of OOC was performed to better organize the pathology. Materials and methods: Subjects with jawbone cysts lined by keratinized stratified squamous epithelium from 2005 to 2018 were reclassified, and clinico-histopathological findings were analyzed. Previous reports of OOC/orthokeratinized-type odontogenic keratocyst (OKC) from 1980 to 2019 were organized. Results: Five cases of OOC were diagnosed, representing 2.1% of odontogenic developmental cysts (total, 239 cases). Mean age was 37.6 years, with a female predominance. The mandibular molar area was the frequent site, and all cysts were solitary. Sixty percent involved an impacted tooth. Mean maximum diameter of the cyst was 2.2 cm. Histopathologically, 4 cases were unilocular, and partial palisading of the basal layer and scattered epithelial islands were observed in 2 cases each and formation of daughter cysts was noted in 3 cases. Previous papers described that most were unilocular and related to impacted teeth. Mean age ranged between 20 and 40 years, and the mandibular molar region was dominant. Recurrence rates were low. Conclusion: OOC shows a different biological attitude to OKC and is closer to dentigerous cyst. Meanwhile, OOC shows a similar histology of epidermoid cysts accompanying the granular layer. We thus surmised that OCC represents an independent concept as an odontogenic developmental cyst.展开更多
基金Supported by Wuhan Morning Light Plan of Youth Science and Technology,No.2017050304010305National Natural Science Foundation of China,No.81702705
文摘BACKGROUND Orthokeratinized odontogenic cyst (OOC) is a benign odontogenic cyst. It is a variant of the common odontogenic keratocyst (OKC). This case report describes a rare malignant transformation of OOC, with the aim of raising awareness of the malignant potential of OOC and distinguishing it from OKC. CASE SUMMARY In August 2018, a 52-year-old man was referred to the Department of Oral Maxillofacial and Head–Neck Oncology of Wuhan University. The patient presented with severe pain in the left mandible for 2 mo, and had a 5-year history of osteomyelitis and mandibular cyst with three recurrences. His latest diagnosis by pathological examination was OOC of the left mandible with mild-tomoderate local proliferation. However, the cyst showed malignant potential by radiographic examination. We performed partial mandibulectomy and sent the lesion tissue for pathological examination. As expected, the cyst had deteriorated to moderately differentiated squamous cell carcinoma. During postoperative follow-up, the patient went for chemotherapy in September 2018 and successfully completed four cycles. CONCLUSION Surgeons should be more aware of OOC, which is usually benign but can become malignant.
文摘Background: With transitions in the disease concept of orthokeratinized odontogenic cyst (OOC), the pathogenesis and etiology have not been sufficiently elucidated. Objectives: OOC cases were reclassified and observed to understand the clinico-histopathological characteristics. In addition, literature review of OOC was performed to better organize the pathology. Materials and methods: Subjects with jawbone cysts lined by keratinized stratified squamous epithelium from 2005 to 2018 were reclassified, and clinico-histopathological findings were analyzed. Previous reports of OOC/orthokeratinized-type odontogenic keratocyst (OKC) from 1980 to 2019 were organized. Results: Five cases of OOC were diagnosed, representing 2.1% of odontogenic developmental cysts (total, 239 cases). Mean age was 37.6 years, with a female predominance. The mandibular molar area was the frequent site, and all cysts were solitary. Sixty percent involved an impacted tooth. Mean maximum diameter of the cyst was 2.2 cm. Histopathologically, 4 cases were unilocular, and partial palisading of the basal layer and scattered epithelial islands were observed in 2 cases each and formation of daughter cysts was noted in 3 cases. Previous papers described that most were unilocular and related to impacted teeth. Mean age ranged between 20 and 40 years, and the mandibular molar region was dominant. Recurrence rates were low. Conclusion: OOC shows a different biological attitude to OKC and is closer to dentigerous cyst. Meanwhile, OOC shows a similar histology of epidermoid cysts accompanying the granular layer. We thus surmised that OCC represents an independent concept as an odontogenic developmental cyst.
