Molecular diagnostics in the differential diagnosis of glandular odontogenic cyst and mucoepidermoid carcinoma - case reports

Clinical and radiologic spectrum of glandular odontogenic cysts: A multicenter study of 92 cases

OBJECTIVE

The purpose of this multicenter retrospective study was to report the clinical and radiologic features of 92 glandular odontogenic cysts (GOCs) diagnosed over a 20-year period.

STUDY DESIGN

Histologically confirmed cases of GOC were retrospectively reviewed from 4 oral pathology laboratories in South Africa and Brazil to categorize the clinical and radiologic spectrum of GOCs.

RESULTS

The mean age of patients was 46 years (range 17-87) with a male-to-female ratio of 1.2:1. GOCs had a mandibular predilection (68%), with 42% of all cases located anteriorly. Additionally, 42% of cases crossed the midline. Radiologically, most lesions were unilocular (53%) and uniformly radiolucent (97%), with well-demarcated borders (93%). Cortical expansion (62%), loss of cortical integrity (71%), and maxillary sinus (67%) and nasal cavity encroachment (72%) were common findings. Significant differences in lesions between the 2 countries were discovered in sex predilection, clinical signs and symptoms, and lesion locations within the mandible and maxilla.

CONCLUSION

GOCs present with a wide spectrum of clinical and radiologic features, ranging from cysts with typical GOC-like presentations to more aggressive lesions. The need for advanced imaging in the surgical planning of GOCs exhibiting radiologic signs of aggression is justified based on the high recurrence rate.

Assessment of biologically aggressive, recurrent glandular odontogenic cysts for mastermind-like 2 (MAML2) rearrangements: histopathologic and fluorescent in situ hybridization (FISH) findings in 11 cases

BACKGROUND

Glandular odontogenic cyst (GOC) demonstrates a significant predilection toward localized biologic aggressiveness and recurrence. GOC shares certain histopathologic features with intraosseous mucoepidermoid carcinoma (IMEC). The current investigation evaluates a group of recurrent, biologically aggressive GOCs to determine whether any cases demonstrated unique histologic features or mastermind-like2 (MAML2) rearrangements common to IMEC.

METHODS

Microscopic slides from 11 previously diagnosed GOCs were stained with hematoxylin and eosin and assessed by 2 study participants for 10 classic histopathologic features required to establish a diagnosis of GOC. Cases were evaluated utilizing break-apart fluorescent in situ hybridization (FISH) analysis for the presence of MAML2 gene rearrangements. Clinical and demographic data on all patients were recorded.

RESULTS

The mean age for patients included in the study was 55.27 years with a range of 36 to 72 years. The most common presenting symptom was a jaw expansion, and all cysts presented initially as a unilocular or multilocular radiolucency. Cysts displayed a minimum of 6 of 10 histologic parameters necessary for a diagnosis of GOC. One case demonstrated MAML2 rearrangements by FISH. That case also showed marked ciliation of cyst-lining epithelial cells and extensive mucous-secreting goblet cell proliferation.

CONCLUSION

Findings in the current study are in concert with previous investigations, and although this study finds only limited molecular evidence to support the premise that recurrent biologically aggressive GOCs are a precursor to IMEC, detection of MAML2 rearrangements in 1 case suggests that such a theoretic transition, while rare, is possible.