MATERIALS AND METHODS: We retrospectively analysed the histopathological material and data from 82 breast cancer patients diagnosed over a period of four years who underwent intraoperative frozen section evaluation of sentinel lymph nodes.
RESULTS: Frozen section analysis detected metastasis in 13 out of 82 cases and definitive pathological examination on the paraffin section confirmed these positive findings. There was no false positive case (specificity of 100%). The true positive cases comprised seven macrometastases, five micrometastases and one isolated tumour cells. Sampling error was noted in two cases in which the malignant cells were only present in the deeper final paraffin sections (false negative rate of 13.3%). The test sensitivity was 86.7% and the accuracy rate was 97.5%. These findings are comparable to other published data.
CONCLUSION: Intraoperative frozen section analysis is a safe and reliable method for assessment of sentinel lymph node. Knowledge on limitation of frozen section analysis with diligent evaluation of frozen section specimen will be beneficial in reducing interpretation error.
CASE PRESENTATION: A 5-year-old Somalian boy with no known medical illness presented with progressive nasal blockage associated with clear nasal discharge and intermittent spontaneous epistaxis for three months. CT paranasal sinus and neck region revealed poorly enhancing expansile mass in the right maxillary sinus with areas of necrosis within. Initial radiological differential diagnoses were lymphoma and rhabdomyosarcoma. The mass was biopsied and histologically showed diffuse sheets of small round blue cells that was positive to CD99, NSE and vimentin. The muscle and lymphoid markers were negative. Fluorescence in-situ hybridisation (FISH) study revealed the presence of EWSR1 gene rearrangement thus diagnosis of ES was rendered.
CONCLUSIONS: ES of sinonasal tract is a rare entity and its pathological features significantly overlap with others small round blue cells tumour. Demonstration of EWSR1 gene translocation is recommended for the diagnosis of ES particularly at uncommon sites.
MATERIALS AND METHODS: Seventy-eight specimens of needle prostate biopsy and its subsequent radical prostatectomy were retrospectively studied. The GSs of the needle biopsy were compared with the corresponding prostatectomy specimens. The percentage of GP4 in GS7 needle biopsy groups was calculated and correlated with the pathological staging.
RESULTS: More than half (60%) of GS 6 needle biopsy cases (PGG 1) were upgraded in the prostatectomy specimen, while the majority (80%) of the GS7 needle biopsy groups (PGG 2 and 3) remain unchanged. Cohen's Kappa shows fair agreement in the Gleason scoring between needle biopsies and prostatectomy specimens, K = 0.324 (95% CI, 6.94 to 7.29), p <0.0005 and in the percentage of GP4 in GS7 needle biopsy groups and their corresponding radical prostatectomy specimens, K = 0.399 (95% CI 34.2 - 49.2), p<0.0005. A significant relationship was seen between the percentage of GP4 in GS7 needle biopsy with the pT and pN stage of its radical prostatectomy (p = 0.008 and p=0.001 respectively).
CONCLUSION: A higher percentage of GP4 in GS7 tumour is associated with worse tumour behaviour, therefore it is crucial for clinicians to realise this in deciding the optimal treatment.
Materials and Methods: This is a retrospective descriptive study. A total of 29 patients diagnosed with MB from January 2005 to December 2015 were included in this study. The MRI brain and spine studies of these patients were retrieved and reviewed by a pediatric radiologist and a neuroradiologist independently, both blinded from the histological type of the MB. The HPE slides were also retrieved and reviewed by a pathologist.
Results: 80% of desmoplastic MB showed the presence of intracranial leptomeningeal seeding and 57.1% of anaplastic MB showed the presence of necrosis. The presence of intracranial leptomeningeal seeding (P = 0.002) and necrosis (P = 0.019) was predictive of the histological subtypes. There is a significant correlation between the enhancement pattern and the 2-year outcome (P = 0.03) with 6 out of 8 patients whose tumors showed minimal enhancement having disease progression within 2 years. A significant correlation was also seen between the presence of necrosis with a poorer outcome (P = 0.03) and between the HPE subtype and 2-year outcome (P = 0.03) with anaplastic MB having the poorest prognosis.
Conclusion: MR imaging features of intracranial leptomeningeal seeding and the presence of necrosis were correlated with a specific histologic subtype of MB. The enhancement pattern as well as necrosis correlated with 2-year poorer outcome of the disease.
OBJECTIVE: The study aims to determine the concordance between HER2 protein IHC score and its gene status by dual-colour dual-hapten in-situ-hybridization (DDISH) study.
MATERIALS AND METHODS: Retrospective study was performed on 767 referred breast cancer cases over a period of five years. The HER2 IHC score (the initial and repeat test score) and the results of HER2 gene status by DDISH were retrieved from the histopathological reports. The agreement between initial IHC score with repeat test score was measured using Cohen Kappa. Chi square test analyzed the association between HER2 IHC score with its gene status by DDISH.
RESULTS: The concordance of HER2 IHC score between the initial and repeat test were 52.7% and 89.4% for IHC score 2+ and 3+ respectively. There was moderate agreement of HER2 IHC score between the initial and repeat test score (ϰ = 0.526, p<0.001). A significant association noted between HER2 IHC score with its gene status by DDISH (p<0.001). Only 56 out of 207 cases (27.1%) with 2+ IHC score showed HER2 gene amplification while the majority of cases with 3+ IHC score were gene-amplified (446 out of 451, 98.9%).
CONCLUSION: ISH study should be done in all IHC-equivocal cases (2+) to select patient for targeted therapy. Gene amplification must also be confirmed in IHC-positive cases (3+) to prevent from giving non-effective treatment with possible adverse effects to patient with non-amplified HER2 gene.
METHODS: This was a multicenter, cross-sectional prevalence study on PD-L1 positivity among patients with advanced-stage TNBC in Malaysia. Patients were identified using medical records and were enrolled in the study if they met the inclusion criteria. PD-L1 evaluation was performed using archived formalin-fixed paraffin-embedded tissue specimens. Demographic and clinical data were also obtained and summarized using descriptive statistics. The association of these parameters with PD-L1 positivity was assessed using chi-square and logistic regression analysis.
RESULTS: Three medical centers provided 138 complete cases for analysis. Of these 138 cases, 52 (37.7%; 95% confidence interval, 29.6%-46.3%) showed positive PD-L1 expression, defined as immune cell PD-L1 expression ≥ 1%. In a univariate analysis, stage III of the disease and tumor samples from resected specimens were significantly associated with a positive PD-L1 status. However, further assessment using a multivariate model revealed that only resected tumor samples remained significantly associated with PD-L1 positivity after controlling for disease staging.
CONCLUSION: The prevalence of PD-L1 positivity among patients with stage III or IV TNBC was 37.7%. A significant association was noted between PD-L1 positivity and the tumor tissue obtained from resected specimens. Although the mechanism and clinical significance of this association remain unclear, this finding indicates a possible disparity in the PD-L1 status of samples obtained using surgical resection or biopsy.
Objective: This study aims to determine inter-laboratory variation in HER2 IHC testing through a slide-exchange program between five main reference laboratories.
Method: A total of 20 breast carcinoma cases with different known HER2 expression and gene status were selected by the central laboratory in five testing rounds. Three unstained tissue sections from each case were sent to participating laboratories, which immunostained and interpreted the HER2 immunohistochemistry result. One of the stained slides was sent to one designated participating laboratory for evaluation. Results were analyzed by the central laboratory.
Results: A complete concordance was achieved in six IHC-positive and six IHC-negative cases, its gene status of which was confirmed by in-situ-hybridization (ISH) study. The discordant results were observed in six equivocal cases, one negative case and one positive case with a concordance rate of 50-88.3%. Interestingly, the negative discordant case actually displays tumor heterogeneity. Good inter-observer agreement was achieved for all participating laboratories (k = 0.713-1.0).
Conclusion: Standardization of HER2 testing method is important to achieve optimum inter-laboratory concordance. Discordant results were seen mainly in equivocal cases. Intra-tumoral heterogeneity may impact the final HER2 IHC scoring. The continuous quality evaluation is therefore paramount to achieve reliable HER2 results.