ETV6 Molecular Heterogeneity in Salivary Secretory Carcinoma: A Case Series Report and Literature Review.

BACKGROUND: ETV6 gene rearrangement is the molecular hallmark of secretory carcinoma (SC), however; the nature, frequency, and clinical implications of atypical ETV6 signal patterns by fluorescence in situ hybridization (FISH) has not yet been systematically evaluated in salivary gland neoplasms. METHODS: The clinical, histopathologic, immunohistochemical and molecular features of seven salivary SCs, including four cases with atypical ETV6 FISH patterns, were retrospectively analyzed along with a critical appraisal of the literature on unbalanced ETV6 break-apart in SCs. RESULTS: The patients were four males and three females (31-70 years-old). Five presented with a painless neck mass and two patients with recurrent disease had a history of a previously diagnosed acinic cell carcinoma of the buccal mucosa. Histologically, there were varied combinations of microcystic, papillary, tubular, and solid patterns. All tumors were diffusely positive for S100 and/or SOX10, while 2 cases also showed luminal DOG1 staining. Rearrangement of the ETV6 locus was confirmed in 5/7 cases, of which 3 cases showed classic break-apart signals, 1 case further demonstrated duplication of the ETV6 5`end and the other loss of one copy of ETV6. Two cases harbored ETV6 deletion without rearrangement. Two of the 4 cases with atypical ETV6 FISH patterns represented recurrent tumors, one with widespread skeletal muscle involvement, bone and lymphovascular invasion. Surgical treatment resulted in gross-total resection in all 7 cases, with a median follow up of 9.5 months post-surgery for primary (n = 3) and recurrent disease (n = 1). CONCLUSION: Duplication of the distal/telomeric ETV6 probe represented the most common (26/40; 65%) variant ETV6 break-apart FISH pattern in salivary SC reported in the literature and appears indicative of an aggressive clinical course.

Carcinomas with clear cell features and EWSR1 rearrangements: a report of 3 cases.

Salivary gland and odontogenic neoplasms with extensive clear cell change are rare lesions but have been increasingly characterized over the past decade. Among this heterogeneous group of neoplasms, hyalinizing clear cell carcinoma (HCCC), clear cell odontogenic carcinoma (CCOC), and clear cell myoepithelial carcinoma (CCMC) share a monophasic clear cell morphology and an EWSR1 gene rearrangement. While HCCC is relatively well characterized, there are a limited number of EWSR1-reaarranged CCMC of salivary glands reported, and its clinicopathologic features in relation to HCCC and nonclear cell myoepithelial carcinoma (MC) have not been clarified. This report describes the clinical, morphologic, and immunophenotypic features of 3 carcinomas composed predominantly of clear cells and with EWSR1 rearrangements by fluorescence in situ hybridization. A comparative literature analysis suggests that HCCC, CCMC, and nonclear cell MC of salivary glands are clinically, histopathologically, and molecularly distinct.

A retrospective clinico-pathologic analysis of cemento-osseous dysplasia in a South African patient population.

BACKGROUND: Cemento-osseous dysplasia (COD) is a fibro-osseous jaw bone lesion. The affected bone in COD progressively becomes sclerotic, poorly vascularized and susceptible to secondary osteomyelitis. OBJECTIVE: To provide a clinico-pathologic appraisal of COD in a South African patient population. METHODS: Archived records of 133 patients diagnosed with COD were reviewed for patient demographics, COD location, COD type, osteomyelitis or simple bone cyst secondary to COD. RESULTS: The mean age was 53.4 ± 13.5 years with a 94.7% female predilection. COD mainly affected the mandible (57.1%), followed by involvement of both jaws (38.3%) and maxilla (4.5%). Florid COD was the most prevalent (69.9%), followed by focal COD (18%) and periapical COD (12%). Florid COD showed a clear trend of increasing with age, peaking in the sixth decade and decreasing thereafter. Osteomyelitis and simple bone cyst presented as complications of COD in 74.4% and 5.3% of cases respectively, while 21.8% of all cases of jaw osteomyelitis during the study period were secondary to COD. CONCLUSION: A higher frequency of jaw osteomyelitis secondary to COD was found compared to previous studies. No significant association was shown between any of the COD types and secondary osteomyelitis.

Internal morphology of ameloblastomas: a study of 24 resected specimens.

OBJECTIVES: The objectives of this study were to describe the internal macroscopic architecture of resected specimens of ameloblastoma and to correlate the findings with radiographs and microscopic features. STUDY DESIGN: Resection specimens of 24 ameloblastomas were retrieved from the files of the Department of Oral Pathology at the University of Limpopo. The neoplasms were sectioned in parallel slices and the macroscopic features recorded and each slice was radiographed and sampled for microscopic examination. The macroscopic features were correlated with respective microscopic and radiological appearances. RESULTS: Twenty-three ameloblastomas affected the mandible and 1 the maxilla and measured between 3.3 and 20 cm in greatest diameter. Six cases were unicystic, 2 of which showed incomplete septae both of which presented multilocular on radiographs. Intracystic proliferations were present in 15 cases. These proliferations showed macroscopic features of either small or large nodules with or without the formation of confluent plaques, focal papillary lesions, or multinodular masses that protruded into the cystic cavities. Microscopically these proliferations were characterized by foci of inflammation or plexiform or solid epithelial proliferations, one of which showed a focus of carcinoma in situ, adenomatoid differentiation and another osteodentin deposits. Seven cases had foci of stromal desmoplastic change, one of which exhibited mineralized deposits resembling bone. CONCLUSIONS: The assessment of the cystic nature of ameloblastomas on 2-dimensional radiographs is inaccurate. Intraluminal proliferations, in situ carcinomatous change, adenoid differentiation, stromal osteodentin, and bone deposits and desmoplasia were found to be focal rather than generalized phenomena in resection specimen of ameloblastoma.