Ki67 and salivary cancer

Myb Immunohistochemical Staining and Fluorescence in situ Hybridization in Salivary Rare Basaloid Lesions

Objective: Salivary rare basaloid lesions, including cribriform type basal cell adenoma (cBCA), BCA with incomplete capsule (iBCA), sialoblastoma (SB), and intercalated duct hyperplasia (IDH), could easily be misdiagnosed as adenoid cystic carcinoma (AdCC). We aim to identify an approach for differential diagnosis and to establish an optimal workflow concerning the diagnosis of these lesions. Material and methods: A panel of antibodies (MYB, β-catenin, CD117, SOX10, ki67, P63, calponin) and fluorescence in situ hybridization (FISH)-MYB were utilized to distinguish above salivary basaloid diseases from AdCC. Results: Histologically, the striking diagnostic features of cBCA, iBCA, SB, and IDH are composed of basaloid tumor cells, well-defined encapsulation, or lack of destructive invasion. Immunohistochemically, Myb immune-labeling could effectively make a distinction among cBCA, iBCA, SB, and IDH from AdCC, except in SB. cBCA and iBCA typically expressed β-catenin in the nuclei of tumor cells. There was no statistical significance in the ki67 index between SB and AdCC, but their indices were significantly higher than those of iBCA and IDH (p < 0.05, p < 0.05, respectively). P63 and calponin immune-expression were observed in the basaloid or myoepithelial cells. CD117 were observed positively in cBCA, iBCA, SB, and AdCC, except in IDH. SOX10 were observed positively in all cases. No cases had fusion of MYB and NFIB detectable by FISH, except in AdCC. Conclusion: Considering their sensitivity and specificity, FISH-Myb and an immunohistochemical panel of MYB/β-catenin/ki67 would be an optimal choice for the differential diagnosis of these basaloid lesions. Clinical relevance: Some salivary basaloid tumor or tumor-like lesions have overlapping features with AdCC. Through this present research, we suggested that the panel IHC of MYB, βcatenin, and ki67 combined with FISH-Myb should be an optimal choice for differential diagnosis among those lesions.

Immunohistochemical features of carcinoma ex pleomorphic adenoma and pleomorphic adenoma in the lacrimal gland

AIM

To investigate C-myc, Ki-67, pan-cytokeratin, and vimentin immunohistochemical features of carcinoma ex pleomorphic adenoma (Ca-ex-PA) and pleomorphic adenoma (PA) in the lacrimal gland in order to find some clues in the differential diagnosis between them.

METHODS

We reviewed microscopic slides and clinical records of 64 cases of PA and 15 cases of Ca-ex-PA in the lacrimal gland. Immunohistochemical antibodies for C-myc, Ki-67, pan-cytokeratin, and vimentin were employed.

RESULTS

Median age of PA was 43.2y (from 21 to 75). The 35 patients (54.7%) were male and 29 patients (45.3%) were female. For the PAs, the average positivity of C-myc was 4.6%; the average proliferation index of Ki-67 was 3.2%; pan-cytokeratin was positive in ductal cells, and vimentin was positive in myoepithelial cells. Median age of Ca-ex-PA was 54.3y (from 26 to 76). There were 7 male patients (46.7%) and 8 female patients (53.3%). Among 15 Ca-ex-PAs, there were 6 myoepithelial carcinomas, 4 adenocarcinomas, 3 epithelial-myoepithelial carcinomas, and 2 squamous cell carcinomas. For the Ca-ex-PAs, the average positivity of C-myc was 36.4%; the average proliferation index of Ki-67 was 29.2%; pan-cytokeratin was positive in all cases, and vimentin was positive in myoepithelial carcinomas.

CONCLUSION

PA has a lower positivity of C-myc and Ki-67, while Ca-ex-PA had a higher positivity of these two biomarkers. These four biomarkers as a set could provide valuable clues in the differential diagnosis between Ca-ex-PA and PA. Our results indicate that the activation of C-myc could play an important role in the pathogenesis of Ca-ex-PA and PA.

Immunohistochemical features of lacrimal gland epithelial tumors

PURPOSE

To investigate the immunohistochemical features of ocular adnexal pleomorphic adenoma and adenoid cystic carcinoma.

DESIGN

Retrospective clinicopathologic study.

METHODS

Clinical records and microscopic slides of 7 cases of each tumor type were reviewed. Immunohistochemical probes for Ki-67 and p53, and newer nuclear markers MYB for adenoid cystic carcinoma and PLAG1 for pleomorphic adenoma, were employed.

RESULTS

Pleomorphic adenomas were asymptomatic, whereas adenoid cystic carcinomas were painful. No pleomorphic adenomas recurred; 4 adenoid cystic carcinomas recurred, resulting in 3 deaths. Unusual histopathologic variants for which immunohistochemistry proved useful included a myoepithelioma, an atypical pleomorphic adenoma, tubular and solid/basaloid variants of adenoid cystic carcinoma, and a morphologically heterogeneous adenoid cystic carcinoma of a Wolfring gland. For the pleomorphic adenomas, the average Ki-67 proliferation index was 3.8%; p53 was weakly staining, with an average positivity of 18.5%; PLAG1 was strongly positive in all cases; MYB was negative in 5 cases and weakly focally positive in 2 cases. For the adenoid cystic carcinomas, the average Ki-67 proliferation index was 29.1%; p53 stained positively and strongly with an average of 39%; none stained positively for PLAG1; and 6 out of 7 were MYB positive.

CONCLUSIONS

Between pleomorphic adenoma and adenoid cystic carcinoma, there was no overlap in Ki-67 positivity. Positivity for p53 showed overlap in only one lesion of each type. PLAG1 and MYB positivity were highly discriminating between pleomorphic adenoma and adenoid cystic carcinoma. Immunohistochemical analysis should be investigated further for its role in the evaluation of pleomorphic adenoma and adenoid cystic carcinoma.

Prognostic significance of Ki-67 in salivary gland carcinomas

BACKGROUND

Salivary gland carcinomas are a heterogeneous group of tumors with varying malignant potential. In this study, we evaluated the proliferative marker Ki-67 in salivary gland carcinomas and related the Ki-67 index to clinical data.

METHODS

A total of 176 salivary gland carcinomas of 13 different subtypes were stained immunohistochemically for Ki-67. The number of Ki-67 positive cells was counted and the Ki-67 index was calculated as the percentage of positive tumor cells.

RESULTS

The Ki-67 median value was 26 (range 1-99). The median follow-up time was 6.9 years (range 0-19 years). The 5- and 10-year crude survival was 70% and 59%, respectively. In univariate analysis, Ki-67 index, stage, vascular invasion and tumor grade were significantly related to crude survival, but in multivariate analysis only Ki-67 index, age, and stage were independent prognostic factors.

CONCLUSION

We showed that irrespective of subtyping, grading or morphological appearance of tumor, the Ki-67 index is an important and independent prognosticator. Clinical and histo-pathological data must be considered, when planning the treatment of the individual patient. We have shown that besides stage and age of the patient, Ki-67 is a strong, independent prognostic factor.

Impact of WWOX alterations on p73, ΔNp73, p53, cell proliferation and DNA ploidy in salivary gland neoplasms

OBJECTIVE

WWOX gene is altered in a variety of neoplasms. Wwox is pro-apoptotic through interaction with p73 and may be involved in chromosomal stability by interaction with p73 and p53. The aims of this study were to characterize WWOX transcription, methylation status and immunoexpression in salivary neoplasms and to determine whether these were associated with p73, p53, cell proliferation and DNA ploidy.

MATERIALS AND METHODS

Seven malignant and 21 benign fresh salivary neoplasms were included. WWOX expression was determined by RT-PCR and sequencing of transcripts, quantitative PCR and immunohistochemistry. Methylation-specific PCR was used to assess the methylation of its first exon. For p73, ΔNp73, p53 and ki67 immunohistochemistry and ploidy analysis, 29 malignant samples from archives were included.

RESULTS

No consistent pattern of WWOX exon 1 methylation was found, but aberrant and novel transcripts were observed in 17/28 neoplasms; 55% of tumours showed reduced WWOX RNA. WWOX RNA levels were associated with p53 immunopositivity. Immunohistochemical Wwox expression did not correlate with methylation status, p53 or p73 expression or proliferation. p73, proliferation and DNA ploidy were associated with malignant phenotype.

CONCLUSION

Aberrant WWOX transcription and decreased expression are frequent in salivary neoplasms and WWOX transcription is associated with p53 staining.

Sialoblastoma: utility of Ki-67 and p53 as a prognostic tool and review of literature

Sialoblastoma is a rare tumor of the salivary gland that commonly occurs in the parotid gland and occasionally in the sub-mandibular gland. The malignant potential of sialoblastoma has been documented in only 3 of 32 cases of sialoblastoma reported thus far. In the last 15 years, we have encountered 2 cases of sialoblastoma, in a newborn and in a 15-year-old boy, both arising within the parotid gland. Case 1 has been previously reported and although there were 2 recurrences, at 1 and 9 years post resection, it has shown benign biological behavior. Case 2 is unusual since the patient presented with metastases. We reviewed the 2 cases, including the 2 recurrences from the first case, for histologic and immunohistochemical differences. Although both cases showed similar cytomorphologic features, there was a significant difference in Ki-67 expression: 20% in case 1 (original tumor), <2% in case 1 (recurrent tumor), and nearly 70-80% in the recent malignant case. The difference is remarkable when combined with p53 expression, which was focally positive in the first case but diffusely positive in the second. This report highlights the potential utility of proliferation markers such as Ki-67 in concert with p53 expression to better predict the biological behavior of a rare but locally aggressive neoplasm.