Non-Calcifying/Langerhans Cell-Rich Calcifying Epithelial Odontogenic Tumour: A Critical Review of the Rare and Distinctive Entity

BACKGROUND

The study aims to analyse the non-calcifying/Langerhans cell rich (NCLC) subtype of calcifying epithelial odontogenic tumour (CEOT).  METHOD: The features of cases of the NCLC subtype of CEOT noted in the English literature by PubMed as well as 3 new cases were reviewed.

RESULTS

Overall, twenty-one cases were noted. Many were women in the fourth to sixth decades (male-to-female ratio =1 to 2). Radiologically, the lesion is often unilocular with resorption of the affected teeth. Nineteen of the 21 cases occurred in the maxilla, especially the anterior portion. On pathological examination, epithelial cells are noted in non-calcifying amyloid-rich fibrous stroma. The main differential diagnosis is the amyloid subtype of central odontogenic fibroma. Immunohistochemical studies revealed the tumour epithelial cells were positive for cytokeratins and p63 and contained CD1a, S-100, and langerin-positive Langerhans cells. On a median follow-up of 2 years, one patient had a recurrence one year after curettage.

CONCLUSION

The NCLC subtype of CEOT is unique as it contains significant numbers of Langerhans cells and has clinicopathological features distinctive from classic CEOT.

Efficacy of marine cyanobacterium Oxynema thaianum ALU PBC5 against multi drug resistant Gram negative pathogens

AIM

Emergence of extended antibiotic resistance among several human bacterial pathogens often leads to the failure of existing antibiotics to treat bacterial infections worldwide. Hence, the present study is aimed to explore antibacterial activity of marine cyanobacterium against MDR pathogens.

METHODS AND RESULTS

The cyanobacterial samples were collected and isolated from Thondi Palk Strait region. The isolate was subjected to polarity based solvent extraction and checked for their antibacterial activity against test bacterial pathogens. The active principles from chloroform extract of Oxynema thaianum (CEOT) were partially purified through thin layer chromatography (TLC). The active principle with highest activity was further characterized by FTIR, high performance liquid chromatography (HPLC) and gas chromatography mass spectrometry (GC-MS) analysis. Among the eight extracts tested, CEOT showed effective zone of clearance against ESBL producing Escherichia coli and Klebsiella pneumoniae in disc diffusion method. In TLC, all the purified five fractions were eluted and tested for their antibacterial activity against test pathogens. The third fraction showing maximum activity was subjected to HPLC analysis for checking its purity. In GC-MS analysis, 9-octadecenoic acid, methyl ester and hexadecanoic acid were identified as the major chemical compounds.

CONCLUSION

Hence, the present study was concluded that O. thaianum ALU PBC5 is a promising agent to treat ESBL producing MDR bacterial pathogens.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the pioneer study on screening and isolation of bioactive compounds from the marine cyanobacteria against MDR pathogens such as E. coli and K. pneumoniae. Here, 9-octadecenoic acid, methyl ester and hexadecanoic acid were identified as the major chemical compounds through TLC, FTIR, HPLC and GC-MS. From this screen, we identified the bioactive compounds against ESBL producing multidrug resistant pathogens such as E. coli and K. pneumoniae.

CEOT Variants or Entities: Time for a Rethink? A Case Series with Review of the Literature

The first detailed description of calcifying epithelial odontogenic tumor (CEOT) are ascribed to Jens Pindborg, but this tumor was described some years previously. Subsequently, CEOT was included in the 1971 WHO classification of odontogenic tumors and a since then number of variants have been described, which have added confusion to the diagnostic criteria. We aimed to survey the literature on the variants of CEOT, in parallel with a review of our single institution experience of CEOTs. Cases identified were collated, including available clinical, radiological and histological information and then reviewed, taking into account changes in the understanding and classifications of odontogenic tumors since initial diagnosis. We identified 26 cases from 1975 to 2017 for which histological material was available. Of these, only 13 (50%) showed the "classic" histological appearance, whilst two cases were identified as recognized variants. In 11 cases, other diagnoses or a differential diagnosis were preferred, with no agreed diagnosis in four of these. The proliferation fraction (Ki67) in the 10 cases tested was 2.1% ± 0.18. These findings illustrate the diagnostic challenges in this group of tumors and highlight the gaps in knowledge. Techniques, such as EWSR1 gene cytogenetic analysis, may be helpful in cases with clear cells. However, in other areas of controversy, including the non-calcifying and Langerhans cell rich variants, further investigation, perhaps utilizing sequencing technologies may be needed to refine the classification. Owing to the relative rarity of these lesions it would be beneficial if future work could be pursued as an international collaboration.

Non Calcifying Type of Calcifying Epithelial Odontogenic Tumor: An Unusual Case Report with Special Emphasis on Histogenesis of Calcifications

Calcifying epithelial odontogenic tumour also known as Pindborg tumour, is a rare benign odontogenic neoplasm of locally aggressive behavior. It is thought to arise from the epithelial element of the enamel origin which are reminiscent of the cells in the stratum intermedium layer of enamel organ in tooth development. The tumour is characterized histologically by the presence of polygonal epithelial cells, calcifications and eosinophilic deposits resembling amyloid. Non-calcifying epithelial odontogenic tumours are very rare and unusual. Only five cases have been reported in the English literature till date. Here, we present an additional case of non calcifying type along with a review of previously reported cases. It has a much lower recurrence and malignant transformation rate.

Peripheral Clear Cell Variant of Calcifying Epithelial Odontogenic Tumor: Case Report and Review of the Literature

Calcifying epithelial odontogenic tumor (CEOT) is classified as an uncommon, benign, odontogenic neoplasm that is exclusively epithelial in origin. Of all reported cases, peripheral tumors account for 5-6 %, among which clear cell variants are still rare. A rare case of peripheral clear cell variant of CEOT occurring in the mandibular gingiva of a 47-year-old female is presented.

Peripheral calcifying epithelial odontogenic tumor - Case report

The calcifying epithelial odontogenic tumor (CEOT), Pindborg tumor is a benign, slow growing, but locally invasive neoplasm. It is known to have a common intraosseous variant and a very rare extraosseous variant. We report an unusual case of an extraosseous variant of CEOT of unusual large size and maxillary anterior location, the treatment was planned considering the clinical, radiological and histological features. Though peripheral types are less aggressive and had no recurrence, in our case regular follow up is required considering the aggressiveness of the lesion and its proximity to important adjacent structures.

Giant pindborg tumor (calcifying epithelial odontogenic tumor): an unusual case report with radiologic-pathologic correlation

Odontogenic tumors develop in the jaws from odontogenic tissues such as enamel organ, Hertwig epithelial root sheath, dental lamina, and so on. A variety of tumors unique to the maxilla and mandible are therefore seen. Calcifying epithelial odontogenic tumor (CEOT) is a rare, aggressive, benign odontogenic tumor of epithelial origin accounting for only about 1% of all odontogenic tumors. It is eponymously called “Pindborg tumor”, as it was first described by Pindborg in 1955. The origin of this locally invasive tumor remains unknown. It is thought to arise from stratum intermedium. It commonly affects the posterior mandible manifesting as a slow-growing asymptomatic swelling often associated with an impacted tooth. We report a case of CEOT, for which, owing to its huge size we have proposed the term “giant” Pindborg tumor (CEOT). This is probably the largest case of this tumor reported so far in the English literature. The present case also has the classic yet rare “driven snow” appearance of the tumor on radiographs.

Calcifying epithelial odontogenic tumor (Pindborg tumor)

The calcifying epithelial odontogenic tumor (CEOT) is a rare entity and represents less than 1% of all odontogenic tumors. Dr. J J Pindborg (1958) first described four cases of this unusual lesion; subsequently Shafer et al coined the term Pindborg tumor. This lesion is a locally aggressive benign odontogenic neoplasm arising from epithelial tissue. It occurs most commonly in 4(th)-5(th)-6(th) decade of life and bears no gender predilection. A case of CEOT in a 50-year-old male arising in the left body region is described.