Challenging pitfalls in frozen section pathology: a case of mandible ghost cell odontogenic carcinoma and the literature review.

BACKGROUND: Ghost cell odontogenic carcinoma (GCOC) is a rare malignancy characterized by the presence of ghost cells, preferably in the maxilla. Only slightly more than 50 case reports of GCOC have been documented to date. Due to the rarity of this tumor and its nonspecific clinical criteria, there is a heightened risk of misdiagnosis in clinical examination, imaging findings, and pathology interpretation. CASE PRESENTATION: A 50-year-old male patient presented to the hospital due to experiencing pain in his lower front teeth while eating for the past 2 months. Upon examination, a red, hard, painless mass was found in his left lower jaw, measuring approximately 4.0 cm × 3.5 cm. Based on the malignant histological morphology of the tumor and the abundant red-stained keratinized material, the preoperative frozen section pathology misdiagnosed it as squamous cell carcinoma (SCC). The surgical resection specimen pathology via paraffin section revealed that the tumor was characterized by round-like epithelial islands within the fibrous interstitium, accompanied by a large number of ghost cells and some dysplastic dentin with infiltrative growth. The malignant components displayed marked heterogeneity and mitotic activity. Additionally, a calcified cystic tumor component of odontogenic origin was observed. Hemorrhage, necrosis, and calcifications were present, with a foreign body reaction around ghost cells. Immunoreactivity for ß-catenin showed strong nuclear positivity in tumor cells, while immunostaining was completely negative for p53. The Ki67 proliferation index was approximately 30-40%. The tumor cells exhibited diffuse CK5/6, p63, and p40 immunoreactivity, with varying immunopositivity for EMA. Furthermore, no BRAFV600E mutation was identified by ARMS-PCR. The final pathology confirmed that the tumor was a mandible GCOC. CONCLUSION: We have reported and summarized for the first time the specific manifestations of GCOC in frozen section pathology and possible pitfalls in misdiagnosis. We also reviewed and summarized the etiology, pathological features, molecular characteristics, differential diagnosis, imaging features, and current main treatment options for GCOC. Due to its rarity, the diagnosis and treatment of this disease still face certain challenges. A correct understanding of the pathological morphology of GCOC, distinguishing the ghost cells and the secondary stromal reaction around them, is crucial for reducing misdiagnosis rates.

Ameloblastic carcinoma: A systematic review.

BACKGROUND: Ameloblastic carcinoma (AC) is the most common odontogenic malignancy, constituting approximately 30% of cases in this category. Literature is sparse on malignant odontogenic neoplasms, with a large proportion of current knowledge derived from case reports or small case series. METHODS: A systematic review of case series/case reports of AC was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Statement guidelines. Demographic and clinical information, including duration of the lesion, location, clinical presentation and radiologic features, were analysed. Additionally, the origin of the lesion (primary/secondary), Ki-67 proliferation index, treatment performed, metastasis, tumour recurrence and prognosis were collected for analysis. RESULTS: A total of 126 studies, including 285 individual cases of AC, were included in this review. Patients presented with a near-equal distribution of painless and painful swellings. ACs presented at a median age of 45 years, with a male-to-female ratio of 1:2. The mandible was most frequently involved, with rare cases extending to involve more than one region, including crossing the midline. Although most lesions presented with poorly-demarcated borders (52.6%), unilocular lesions with well-demarcated borders (47.4%) comprised a substantial number in the sample. The proliferation index was only reported in 27 cases, with a mean score of 42% and a wide range. The probability of tumour recurrence increased, and the survival probability decreased with prolonged follow-up duration. CONCLUSION: This study provides more comprehensive, up-to-date descriptive data on these rare odontogenic malignancies, aiding clinicians and Pathologists with the diagnosis and surgeons in their management of cases.

Immunohistochemical Expression of CK14 and Bcl-2 in Odontogenic Keratocyst and Its Variants.

Odontogenic keratocysts (OKCs) are aggressive cystic jaw lesions with a high epithelial turnover rate and increased propensity for recurrence. Sometimes, the characteristic histopathological features of OKCs are either completely lost or seen focally due to previous marsupialization or inflammation. This research aimed to determine whether specific patterns of CK14 and Bcl-2 staining could assist in diagnosing OKCs with altered epithelial features and provide clues in elucidating their aggressive nature. CK14 expression was restricted to basal and suprabasal layers near satellite cysts and in areas showing subepithelial split. The entire epithelial lining showed CK14 expression in areas of inflammation and after marsupialization. The typical basal/suprabasal staining of Bcl-2 was lost in areas of inflammation and intensity is decreased in OKCs after marsupialization. These new findings could offer a hint into the biological nature and pathogenesis of OKCs. Because of its therapeutic consequences and high recurrence rate, proper recognition and diagnosis are essential for treatment planning.

CD1a is not effective in distinguishing calcifying epithelial odontogenic tumors from amyloid-rich central odontogenic fibroma.

OBJECTIVE: Differential diagnosis between the non-calcifying variant of calcifying epithelial odontogenic tumor (NCLC-CEOT) and amyloid-rich central odontogenic fibroma (AR-COdF) has become a debate, particularly regarding the frequency of CD1a positivity in both entities. This has led to the growing consensus that CD1a-positive staining in AR-NC lesions confirms the diagnosis of AR-COdF. Here, we assess the validity of this consensus. STUDY DESIGN: We collected the data of a case series of histopathologically distinct CEOTs, NCLC-CEOTs, and COdFs and stained them for CD1a and amyloid. Of the 9 CEOTs and NCLC-CEOTs, we diagnosed 4 as classic, 3 as associated with a dentigerous cyst, and 2 as combined CEOT/adenomatoid odontogenic tumors. Of the 9 COdFs, we diagnosed 3 as epithelial poor, 3 as epithelial rich (lacking amyloid), 2 as hyalinized with amyloid, and 1 as hyalinized without amyloid and assessed the staining results. RESULTS: Of the 9 CEOTs and NCLC-CEOTs, 7 stained positively for CD1a, 5 diffusely and 2 focally. Notably, 2 classic NCLC-CEOTs stained strongly CD1a positive. All 3 of the epithelial-poor COdFs were predictably CD1a negative. Of the 6 remaining COdFs, 2 were CD1a positive, 1 hyalinized-with-amyloid COdF diffusely and 1 epithelial-rich-without amyloid focally. CONCLUSIONS: CD1a positivity, which occurs in classic CEOT and NCLC-CEOT, does not help distinguish between NCLC-CEOT and AR-COdF and is inconsistent in all AR-COdFs. The diagnosis of CEOT and AR-COdF should be guided by appropriate histopathologic criteria irrespective of CD1a staining or the presence of amyloid or calcifications.

Pediatric Odontogenic Tumors.

Odontogenic tumors are rare tumors of the jaws that arise from remnants of the tooth forming apparatus. Some odontogenic tumors demonstrate strong predilection for pediatric patients including the unicystic ameloblastoma, adenomatoid odontogenic tumor, ameloblastic fibroma, ameloblastic fibro-odontoma, odontoma, and primordial odontogenic tumor. In this review, we discuss the clinical, radiographic, histopathologic, and molecular characteristics of select odontogenic tumors that demonstrate pediatric predilection and review management.

Ghost cell odontogenic carcinoma: A rare case report and review of literature.

RATIONALE: Ghost cell odontogenic carcinoma is a rare malignant odontogenic carcinoma characterized by the presence of ghost cells. It has a nonspecific clinical and radiographic presentation and can be locally destructive and invasive, sometimes with distant metastases. However, no effective systemic therapy is currently recommended for such patients. PATIENT CONCERNS: The patient has been unable to undergo surgery or radiotherapy again. Therefore, he was referred to our department for a more aggressive, multimodal systematic treatment program. DIAGNOSES: The histopathological examination was morphologically suggestive of ghost cell odontogenic carcinomas. INTERVENTIONS: We report a case of locally invasive primary inoperable odontogenic shadow cell carcinoma in a 31-year-old Chinese man who achieved treatment with Toripalimab and chemotherapy, followed by Toripalimab maintenance therapy after 6 cycles. OUTCOMES: He achieved partial remission after treatment. The quality of life significantly improved after treatment. There were no grade 3/4 treatment-related adverse events during treatment. LESSONS: This case presented that Toripalimab and chemotherapy may be a safe and effective systemic therapy for ghost cell odontogenic carcinoma.

Metastasising ameloblastoma or ameloblastic carcinoma? A case report with mutation analyses.

BACKGROUND: Ameloblastic carcinoma and metastasising ameloblastoma are rare epithelial odontogenic tumours with aggressive features. Distinguishing between these two lesions is often clinically difficult but necessary to predict tumour behaviour or to plan future therapy. Here, we provide a brief review of the literature available on these two types of lesions and present a new case report of a young man with an ameloblastoma displaying metastatic features. We also use this case to illustrate the similarities and differences between these two types of tumours and the difficulties of their differential diagnosis. CASE PRESENTATION: Our histopathological analyses uncovered a metastasising tumour with features of ameloblastic carcinoma, which developed from the ameloblastoma. We profiled the gene expression of Wnt pathway members in ameloblastoma sample of this patient, because multiple molecules of this pathway are involved in the establishing of cell polarity, cell migration or for epithelial-mesenchymal transition during tumour metastasis to evaluate features of tumor behaviour. Indeed, we found upregulation of several cell migration-related genes in our patient. Moreover, we uncovered somatic mutation BRAF p.V600E with known pathological role in cancerogenesis and germline heterozygous FANCA p.S858R mutation, whose interpretation in this context has not been discussed yet. CONCLUSIONS: In conclusion, we have uncovered a unique case of ameloblastic carcinoma associated with an alteration of Wnt signalling and the presence of BRAF mutation. Development of harmful state of our patient might be also supported by the germline mutation in one FANCA allele, however this has to be confirmed by further analyses.

Proceedings of the 2023 North American Society of Head and Neck Pathology Companion Meeting, New Orleans, LA, March 12, 2023: Odontogenic Tumors: Have We Achieved an Evidence-Based Classification.

BACKGROUND: The World Health Organization's (WHO) chapter on odontogenic and maxillofacial bone tumors provides a global reference for diagnosis of these tumors. In the fifth edition, the inclusion of consensus definitions and development of essential and desirable diagnostic criteria help improve recognition of distinct entities. These are key enhancements since the diagnosis of odontogenic tumors is largely based on histomorphology which is taken in combination with clinical and radiographic appearances. METHODS: Review. RESULTS: Despite delineation of diagnostic criteria for ameloblastoma, adenoid ameloblastoma, and dentinogenic ghost cell tumor, a subset of these tumors continues to show overlapping histological features that can potentially lead to misdiagnosis. Accurate classification may be challenging on small biopsies, but potentially enhanced by refining existing diagnostic criteria and utilization of immunohistochemistry and/or molecular techniques in a specific cases. It has become clear that the clinical and histologic features of the non-calcifying Langerhans cell-rich subtype of calcifying epithelial odontogenic tumor and the amyloid-rich variant of odontogenic fibroma converge into a single tumor description. In addition, this tumor shows remarkable clinical, histological overlap with a subset of sclerosing odontogenic carcinoma located in the maxilla. Benign perineural involvement vs perineural invasion is an underexplored concept in odontogenic neoplasia and warrants clarification to reduce diagnostic confusion with sclerosing odontogenic carcinoma. CONCLUSION: While controversial issues surrounding classification and discrete tumor entities are addressed in the WHO chapter, ambiguities inevitably remain. This review will examine several groups of odontogenic tumors to highlight persistent knowledge gaps, unmet needs and unresolved controversies.

Exuberant clear cell odontogenic carcinoma of the mandible harboring EWSR1 rearrangement: Report of a rare case and a literature review.

Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic tumour (MOT) that mainly affects the mandible, with a slight female predominance in adult patients. In this study, we described an exuberant CCOC in mandible of a 22-year-female patient. On radiographic examination, a radiolucent lesion in the region of tooth 36 to 44 with tooth displacement and alveolar cortical resorption was observed. Histopathological study revealed a malignant neoplasm of the odontogenic epithelium, composed of PAS-positive clear cells and immunoreactivity for CK5, CK7, CK19, p63. The Ki-67 index was low (<10 %). Fluorescent in situ hybridization revealed EWSR1 gene rearrangement. The diagnosis of CCOC was established and the patient was referred for surgical treatment.

Diagnostic significance of NM23 protein in ameloblastoma and ameloblastic carcinoma: An immunohistochemical study.

BACKGROUND: Clinico-histopathologic assessment of patients with ameloblastoma and ameloblastic carcinoma remains the best diagnostic modality for the tumors. However, in cases where the criteria for arriving at a definitive diagnosis are not clearcut, the pathologist is faced with a dilemma and thus an imperative need for adjunct diagnostic methods. OBJECTIVES: To evaluate/compare the immunohistochemical expression of NM23 in classical, borderline (atypical) ameloblastoma and ameloblastic carcinoma and to assess usefulness of NM23 in closing diagnostic gaps between ameloblastoma and ameloblastic carcinoma. METHODS: Twenty-four (24) cases of ameloblastoma, 10 ameloblastoma with classical histopathologic features, 8 with nonclassical histopathology [atypical], and 6 cases of ameloblastic carcinoma were selected from cases seen at the Oral Pathology Laboratory of the Lagos State University College of Medicine, Nigeria. NM23 immunostaining protocol was done on the selected tissue blocks and evaluated using Sinicrope method. Analysis was done using R language. RESULTS: Positive NM23 staining was observed in all cases of ameloblastoma and ameloblastic carcinoma, with more intense staining observed in the stellate reticulum-like areas than in the ameloblast-like areas. Ameloblastic carcinoma stained intensely with NM23 (100%) compared with atypical cases (37.5%) and ameloblastoma (20.0%; p = 0.04). The mean aggregate score was also significantly higher in AC (11 ± 2.4; p = 0.01). The mean aggregate score was also significant amongst growth pattern of ameloblastoma (p = 0 0.02). CONCLUSIONS: The findings in this study reveal the usefulness of NM23 in differentiating ameloblastoma from ameloblastic carcinoma; a more comprehensive study with a larger sample size is recommended to corroborate or refute the findings in this study.

Transformation of ameloblastoma to ameloblastic carcinoma in a 10-year-old child.

Ameloblastic carcinoma (AC) is a rare odontogenic malignant epithelial neoplasm of maxillofacial skeleton with a distinct predisposition of the mandible. It can occur in a wide range of age groups, with a sex predilection in males. It can arise either as a de novo lesion or from preexisting ameloblastoma. AC has a high propensity for local recurrence as well as distant metastasis (chiefly lungs), thus requiring an aggressive surgical approach and a strict surveillance. Owing to the rarity of publications describing AC, little is known about this entity in pediatric patients. We report a case of transformation of ameloblastoma into AC in a 10-year-old child.

Peripheral ameloblastoma: case report and our experience 20 years.

BACKGROUND AND AIM: The purpose of this study was to determine the clinical and histological features and treatment of peripheral ameloblastoma. Peripheral Ameloblastoma is a rare benign odontogenic tumor that concerns soft tissue and have a typical extraosseous localization. METHODS: Aim of this work is to show its clinical and histological characters, in order to define some useful information for differential diagnosis with other oral neoformations, comparing literature with our data, collected in ten years of clinical activity of Oral and Maxillofacial Surgery Unit of Policlinico Tor Vergata in Rome. RESULTS: Prognosis of PA is certainly favourable, with a restitutio ad integrum close to 100%. In the period between October 2011 and November 2021, we reported 8 diagnoses of P.A. Medium age of the group with diagnosis of PA was 71,4 y with a SD: 3,65. P.A.'s incidence in our sample of patients was 0,26%. CONCLUSIONS: PA is a benign odontogenic tumor that requires a careful diagnosis, a complete surgical eradication and adequate follow up, because malignant evolution is rare but possible.

A Large Follicular Adenomatoid Odontogenic Tumor Occupying the Maxillary Sinus: A Case Report.

Adenomatoid odontogenic tumour is a rare benign, odontogenic tumour with uncertain histogenesis. Whether it is a hamartoma or a neoplasm is still a controversial topic. It is usually associated with an unerupted maxillary canine. Here, we discuss a follicular adenomatoid odontogenic tumour in a young girl with uncommon features such as it arose from two unerupted teeth and partial resorption of the roots of other normal teeth. The tumour was large enough to completely occupy the maxillary sinus. It was treated with enucleation and curettage by lateral rhinotomy approach. Keywords: adenomatoid tumor; case reports; hamartoma; odontogenic cysts.

A retrospective study of the malignant change of odontogenic keratocyst.

The odontogenic keratocyst (OKC) is a common cystic lesion of the maxilla and mandible. Squamous cell carcinoma (SCC) arising from OKC or dysplasia occurring in OKC is rare. This study aimed to explore the incidence and clinical features of the dysplasia and malignant transformation of OKC. In this study, 544 patients diagnosed with OKC were collected. Among them, 3 patients were diagnosed as SCC arising from OKC, and 12 patients were diagnosed as OKC with dysplasia. The incidence was calculated. Clinical features were analyzed by chi-square test. In addition, a representative case reconstructing mandible with vascularized fibula flap under general anesthesia was reported. And cases reported before were reviewed. The incidence of the dysplasia and malignant transformation of OKC, which are highly associated with the clinical features of swelling and chronic inflammation, is about 2.76%. But the relevance between the dysplasia and malignant transformation and age, gender together with pain is not statistically high. All in all, the clinical features of swelling and chronic inflammation can be considered as characteristics of the dysplasia and malignant transformation of OKC. Although the pain isn't statistically relevant, it may be a dangerous clew. Also, combined with earlier literatures, the dysplasia and malignant transformation of OKC shows unique features of radiographs and histopathology.

Focal Abscess: Description of a clinical case.

Purpose The purpose of this article is to present a case report of a periapical lesion found in a 24-year-old female who presented to a university dental hygiene clinic with a chief complaint of vestibular pain around tooth #22. Radiographically, the lesion appeared radiolucent and unilocular with well-defined borders and significant bone resorption. The area of radiolucency increased in size over a period of five weeks indicating an aggressive pathosis. Given the clinical and radiographic presentations, the differential diagnosis included an odontogenic keratocystic tumor (odontogenic keratocyst), central giant cell granuloma, periapical cyst, and squamous cell carcinoma. Biopsy revealed the diagnosis of a focal abscess. The patient's presenting signs and symptoms are reviewed. Management and contributing factors are discussed.

Diode laser on excision of giant peripheral odontogenic myxoma: a rare case report and literature review.

It was to report a rare case of peripheral odontogenic myxoma removed with high-power diode laser and to do an extensive review of studies of odontogenic cysts and tumors treated with high-power laser (HPL). This is a rare case of a 63-year-old male patient with a peripheral odontogenic myxoma measuring approximately 10 cm in the attached gingiva region of tooth 16 removed with a high-power diode laser (808 nm, 3 W, in continuous mode, under constant suction, with 400-µm optical fiber). A literature review was also carried out looking for articles that involved the use of HPL in the treatment of odontogenic cysts and tumors, without restriction of year or language. In the present case, there was no need for suturing, no postoperative discomfort, and minimal bleeding during the procedure. In a 12-month follow-up period, there were no signs of recurrence. Only two cases of intra-osseous odontogenic myxomas treated with HPL and 10 cases involving other odontogenic cysts and tumors were found. All studies showing HPL to be effective in treating these lesions. Despite the different types of lasers used and different parameters, it is observed that lasers are effective in the treatment of odontogenic lesions.

Ghost Cell Odontogenic Carcinoma: A Case Report and Literature Review.

Ghost cell odontogenic carcinoma (GCOC) is an exceptionally rare malignant odontogenic neoplasm with a significant potential for aggressive growth. Although the literature on this tumor is limited, its high recurrence rates suggest that early and multimodal intervention may be beneficial. This study reports a case of GCOC of the mandible that was successfully treated with surgical resection, reconstruction, and radiation. A comprehensive literature review was performed, and the relevant genomic and histopathological characteristics of this malignancy were determined. Laryngoscope, 133:830-833, 2023.