Tumor location matters, next generation sequencing mutation profiling of left-sided, rectal, and right-sided colorectal tumors in 552 patients.

Despite the introduction of new molecular classifications, advanced colorectal cancer (CRC) is treated with chemotherapy supplemented with anti-EGFR and anti-VEGF targeted therapy. In this study, 552 CRC cases with different primary tumor locations (250 left side, 190 rectum, and 112 right side) were retrospectively analyzed by next generation sequencing for mutations in 50 genes. The most frequently mutated genes were TP53 in left-sided tumors compared to right-sided tumors and BRAF in right-sided tumors compared to left-sided tumors. Mutations in KRAS, NRAS, and BRAF were not detected in 45% of patients with left-sided tumors and in 28.6% of patients with right-sided tumors. Liver metastases were more common in patients with left-sided tumors. Tumors on the right side were larger at diagnosis and had a higher grade (G3) than tumors on the left. Rectal tumors exhibit distinctive biological characteristics when compared to left-sided tumors, including a higher absence rate of KRAS, NRAS, and BRAF mutations (47.4% in rectal versus 42.8% in left-sided tumors). These rectal tumors are also unique in their primary metastasis site, which is predominantly the lungs, and they have varying mutation rates, particularly in genes such as BRAF, FBXW7, and TP53, that distinguish them from tumors found in other locations. Primary tumor location has implications for the potential treatment of CRC with anti-EGFR therapy.

The Frequency of Differentiated Thyroid Cancer Recurrence in 2302 Patients With Excellent Response to Primary Therapy.

CONTEXT: Discrepant data on the recurrence rate of differentiated thyroid cancer (DTC) are reported. OBJECTIVE: To evaluate the frequency and risk factors of true recurrence in DTC patients with excellent responses (ExR) to initial therapy. METHODS: A retrospective analysis of the 2302 consecutive DTC patients with ExR to primary therapy, treated during 24 years at single center. The percentage of recurrence and cumulative recurrence rate (CRR) were analyzed. Risk factors for recurrence for patients with papillary thyroid cancer (PTC) were investigated and methods for establishing a diagnosis of recurrence were evaluated. RESULTS: Of DTC patients, 32 (1.4%) experienced recurrence. PTC patients with recurrence were more likely to have younger age (P = .0182), larger tumor size (P = .0013), lymph node metastases (P = .0013), incomplete resection (P = .0446), higher ATA risk (P = .0002), and had more frequently been treated with 131I (P = .0203). CRRs at 5, 10, 15, 20, and 24 years after surgery were 1.2%, 1.9%, 2.5%, 2.9%, and 2.9%, respectively. The CRRs according to histological type were highest for poorly differentiated thyroid cancer (PDTC), lower for oncocytic (OTC) and follicular thyroid cancer (FTC), and lowest for PTC. Most recurrences occurred within the first 5 years of observation. The most effective method for detecting local recurrence was ultrasonography with fine needle aspiration cytology, and for distant metastases, 18F-FDG PET. CONCLUSION: True recurrence is rare in DTC patients. PTC patients with ExR to primary therapy and N0/Nx can be dismissed from oncological follow-up. Despite ExR to primary therapy, DTC patients with N1, and PDTC, OTC, FTC should remain under oncological follow-up.

CD276 as a Candidate Target for Immunotherapy in Medullary Thyroid Cancer.

Medullary thyroid cancer (MTC) is a rare malignancy, and the treatment of metastatic MTC is challenging. In previous work, immune profiling (RNA-Seq) of MTC identified CD276 as a potential target for immunotherapy. CD276 expression was 3-fold higher in MTC cells than in normal tissues. Paraffin blocks from patients with MTC were analyzed by immunohistochemistry to confirm the results of RNA-Seq. Serial sections were incubated with anti-CD276 antibody, and scored according to staining intensity and the percentage of immunoreactive cells. The results showed that CD276 expression was higher in MTC tissues than in controls. A lower percentage of immunoreactive cells correlated with the absence of lateral node metastasis, lower levels of calcitonin after surgery, no additional treatments, and remission. There were statistically significant associations of intensity of immunostaining and percentage of CD276 immunoreactive cells with clinical factors and the course of the disease. These results suggest that targeting this immune checkpoint molecule CD276 could be a promising strategy for the treatment of MTC.

A Significance of Concomitant BRAFV600E and TERT Mutations in Polish Patients with Papillary Thyroid Microcarcinoma: A Retrospective Cohort Study Based on 430 Cases.

Background: The incidence of papillary thyroid cancer is increasing worldwide due to more frequent pathological detection of papillary thyroid microcarcinomas (PTMC), which are cancers measuring 1 cm or less in diameter. In rare cases, the course of PTMC can be aggressive, with an increased risk of recurrence/persistent disease. The aim of this study of Polish patients diagnosed with PTMC was to assess the impact of concomitant B-type Raf kinas-activating mutation in codon 600 of exon 15 (BRAFV600E) and telomerase reverse transcriptase (TERT) hotspot mutations on clinicopathological features, response to treatment, potential recurrence, and the final outcome. Methods: A retrospective analysis of the 430 PTMC cases diagnosed during 2001-2020 at a single center was performed. All PTMC cases were assessed histopathologically, and analyses of BRAFV600E and TERT promoter were performed based on DNA isolated from tumor blocks. Results: There were 29/430 (6.7% [confidence interval: 4.6-9.5]) patients in whom the TERTC228T and/or TERTC250T mutations coexisted with the BRAFV600E mutation. A statistical comparison between PTMC cases with concomitant BRAFV600E and TERT hotspot mutations and those without any of those mutations revealed no significant differences between the two groups with respect to risk stratification, response to primary treatment, clinical course, or final disease status. Conclusion: Regardless of the molecular background of PTMC, the overall response to therapy is excellent, and long-term disease-free survival rates can be achieved by most patients.

Immune Profiling of Medullary Thyroid Cancer-An Opportunity for Immunotherapy.

Medullary thyroid cancer (MTC) is a rare malignancy that arises from calcitonin-producing C-cells. Curative treatment for patients with metastatic MTC is challenging. Identifying the mechanisms by which cancer cells inhibit the activity of immune cells provides an opportunity to develop new therapies that restore anticancer activity. Little is known about the immunological phenomena underlying MTC. Here, we examined the expression profile of 395 genes associated with MTC. The study included 51 patients diagnosed with MTC at a single center. Bioinformatical analysis revealed that CD276 expression in MTC cells was at least three-fold higher than that in normal tissue. The expression of CD276 showed a weak but statistically significant positive correlation with tumor diameter, but we did not find a significant association between CD276 expression and other histopathological clinical factors, or the response to initial therapy. A search of published data identified the monoclonal antibody (inhibitor) enoblituzumab as a potential drug for patients diagnosed with MTC overexpressing CD276.

Is Male Sex A Prognostic Factor in Papillary Thyroid Cancer?

Identifying risk factors is crucial for predicting papillary thyroid cancer (PTC) with severe course, which causes a clinical problem. The purpose of this study was to assess whether male sex can be such a predictive factor and to verify whether including it as a predictive factor of high initial risk of recurrence/persistence would help to enhance the value of the American Thyroid Association initial risk stratification system (ATA). We retrospectively analyzed 1547 PTC patients (1358 females and 189 males), treated from 1986 to 2018. The relationship between sex and clinicopathological features, response to therapy, and disease status was assessed. Men with PTC showed some adverse clinicopathological features more often than women, including angioinvasion, lymph node metastases, and tumor size > 40 mm. There were sex-related disparities with respect to response to initial therapy and final follow-up. Male sex is associated with some unfavorable clinicopathological features of PTC, which may affect response to initial therapy or final disease status. In our study, modification of the ATA system by including male sex as a risk factor does not enhance its value. Thus, further studies are needed to assess whether males require treatment modalities or oncological follow-up protocols that are different from those of females.

Incidence of the CHEK2 Germline Mutation and Its Impact on Clinicopathological Features, Treatment Responses, and Disease Course in Patients with Papillary Thyroid Carcinoma.

The CHEK2 gene is involved in the repair of damaged DNA. CHEK2 germline mutations impair this repair mechanism, causing genomic instability and increasing the risk of various cancers, including papillary thyroid carcinoma (PTC). Here, we asked whether CHEK2 germline mutations predict a worse clinical course for PTC. The study included 1547 unselected PTC patients (1358 women and 189 men) treated at a single center. The relationship between mutation status and clinicopathological characteristics, treatment responses, and disease outcome was assessed. CHEK2 mutations were found in 240 (15.5%) of patients. A CHEK2 I157T missense mutation was found in 12.3%, and CHEK2 truncating mutations (IVS2 + 1G > A, del5395, 1100delC) were found in 2.8%. The truncating mutations were more common in women (p = 0.038), and were associated with vascular invasion (OR, 6.91; p < 0.0001) and intermediate or high initial risk (OR, 1.92; p = 0.0481) in multivariate analysis. No significant differences in these parameters were observed in patients with the I157T missense mutation. In conclusion, the CHEK2 truncating mutations were associated with vascular invasion and with intermediate and high initial risk of recurrence/persistence. Neither the truncating nor the missense mutations were associated with worse primary treatment response and outcome of the disease.

HPV genotyping and p16/Ki-67 test significantly improve detection rate of high-grade cervical squamous intraepithelial lesion.

INTRODUCTION: Liquid-based cytology allows to apply modern and specific analyses of hrHPV genotyping in p16/Ki-67 test. All of these together could raise accuracy ratio for high-grade squamous intraepithelial lesion above 90%. The purpose of this study was to evaluate the diagnostic accuracy of LBC, hrHPV testing, and p16/Ki-67 testing in diagnosis of high-grade cervical intraepithelial lesions. MATERIAL AND METHODS: The study consisted of 176 women, out of which 50 presented with HSIL (CIN2) SCC (cervical intraepithelial lesion grade 2 squamous cell carcinoma). 126 women with a negative Pap test were pooled into the second group of the study. All patients were resampled for LBC, HPV genotyping, and for the p16/Ki-67 test. The research was carried out between May and December 2017, and second sampling were taken from 1 to 4 months. RESULTS: We reported a strong correlation between positive Pap test and hrHPV (p < 0.05) that met accuracy close to 90%. We noted correlations between a positive p16/Ki-67 with a positive Pap test: p < 0.001; 66% sensitivity (95% CI: 51.2-78.8%), 87.8% specificity (95% CI: 75.2-95.4%), 76.8% accuracy (95% CI: 67.2-84.7%), and OR 13.9 (95% CI: 4.9-39.2), especially HSIL and HPV16: p < 0.001; sensitivity (95% CI) 64.0, specificity (95% CI) 98.4, accuracy (95% CI) 88.6, OR (95% CI) 109.3. CONCLUSIONS: The results of our study indicate hrHPV genotyping as a good biomarker for the triage of patients with an abnormal cytological report. In our opinion, the hrHPV test reaches the highest level of sensitivity, specificity, and accuracy, and should be considered as crucial diagnostic test in cervical screening.

Histopathology and immunohistochemistry as prognostic factors for poorly differentiated thyroid cancer in a series of Polish patients.

BACKGROUND: Poorly differentiated thyroid cancer (PDTC) is a rare but aggressive type of thyroid cancer (TC) and the main cause of death from non-anaplastic follicular cell-derived TC. Although the Turin criteria are well defined, the pathological features that could serve as diagnostic and prognostic factors remain controversial. MATERIALS AND METHODS: Forty-nine consecutive PDTC cases were identified in a single cancer center between 2000 and 2018. We analyzed the impact of routine histopathological and immunohistochemical features and several parameters that are not routinely included in pathology reports such as the presence of atypical mitoses, the amount of necrosis, or insulin-like growth factor-II mRNA-binding protein 3 immunostaining on the survival of patients with PDTC. Overall survival (OS) and disease-specific survival (DSS) were calculated using the Kaplan-Meier method. RESULTS: Of the 49 PDTC 34 (69.4%) showed the insular pattern of growth. The median of poorly differentiated area was 95% (range, 1-100), and 30 (61.2%) patients had a predominant (>50%) insular area. The 5-year OS and DSS rates at a median follow-up of 57 months were 60.6% and 64.3%, respectively. Univariate analysis showed that tumor size >4 cm, presence of atypical mitoses, Ki-67 >5%, and thyroglobulin (Tg)-negative immunostaining were associated with a higher risk of PDTC-related death. Atypical mitoses and Tg negativity were independent factors of worse DSS in multivariate analysis. Patients with insular and predominant insular areas showed a 3- and 6-fold higher risk of PDTC death when they displayed atypical mitoses. CONCLUSIONS: In PDTC, the presence of atypical mitoses may be helpful in identifying patients with poorer outcome and worth including in pathology reports, particularly in tumors with a dominant insular pattern of growth. Additionally, the inclusion of Tg immunostaining may be considered in a prognostic context, and not only as a diagnostic feature.

Does the TT Variant of the rs966423 Polymorphism in DIRC3 Affect the Stage and Clinical Course of Papillary Thyroid Cancer?

Thyroid cancer (TC) is the most common cancer of the endocrine system. Most new diagnoses are of low-grade papillary thyroid cancer (PTC), suggesting that PTC may be over-diagnosed. However, the incidence of advanced-stage PTC has increased in recent years. It is therefore very important to identify prognostic factors for advanced PTC. Somatic mutation of the BRAF gene at V600E, or the coexistence of the BRAF V600E mutation and mutations in the TERT promoter are associated with more aggressive disease. It would also be valuable to identify genetic risk factors affecting PTC prognosis. We therefore evaluated the impact of the rs966423 polymorphism in the DIRC3 gene, including its relationship with unfavorable histopathological and clinical features and mortality, in differentiated thyroid cancer (DTC). The study included 1466 patients diagnosed with DTC from one center. There was no significant association between the DIRC3 genotype at rs966423 (CC, CT, or TT) and any histopathological or clinic factor examined, including initial response to therapy, response at follow-up, or overall mortality, in DTC patients.

Somatic mutations in BRCA1&2 in 201 unselected ovarian carcinoma samples - single institution study.

Ovarian cancer (OC) is the most lethal among gynecologic malignancies worldwide. Unfortunately, in around 70% of cases cancer is diagnosed in late stages (III-IV) which decreases the 5-year survival rate to 25%. The standard of care in ovarian cancer is debulking surgery followed by chemotherapy regimens based on platinum salts. Since 2014 PARP inhibitors became available for OC patients with germline or/and somatic mutations in BRCA1/2, including maintenance therapy. BRCA1/2 Next Generation Sequencing (NGS)-based analysis of formalin-fixed paraffin-embedded (FFPE) ovarian cancer samples becomes the standard of care. The aim of the present study was to evaluate the frequency of mutations in 201 unselected ovarian cancer tissues using the NGS method. In total, pathogenic mutations in both genes were detected in 24% (49/201) of the ovarian cancer cases tested. For 41 patients the results of testing of DNA isolated from blood sample revealed that 17% (35/201) mutations were germline origin, whereas 3% (6/201) mutations were somatic. In 4% (8/201) cases blood sample was inaccessible. The presence of pathogenic mutations was correlated with younger age at diagnosis and serous subtype. Close cooperation between many specialists (gynecologist, pathologist, oncologist, clinical genetics and molecular biologist) is indispensable for efficient and on-time BRCA1/2 ovarian tumor tissue testing.

The Influence of Red Meat on Colorectal Cancer Occurrence Is Dependent on the Genetic Polymorphisms of S-Glutathione Transferase Genes.

BACKGROUND: It is postulated that both individual genotype and environmental factors such as diet may modify the risk of developing colorectal cancer (CRC). The influences of GST gene polymorphism and red meat intake on CRC occurrence in the Polish population were analyzed in this study. METHODS: Genotyping was performed with the qPCR method. RESULTS: A high frequency of meat consumption was associated with an over 2-fold increase in the risk of colorectal cancer odds ratio (OR) adjusted for sex and age = 2.4, 95% confidence interval (CI); 1.3-4.4). However, after analyzing the genetic profiles, in the absence of polymorphisms of all three analyzed genes, there was no association between a high frequency of meat consumption and the occurrence of CRC. In the case of GSTM1 gene polymorphism, the high frequency of meat consumption increased the risk of CRC by almost more than 4 times (OR adjusted for sex and age = 3.8, 95% CI: 1.6-9.1). For GSTP1 gene polymorphism, a 3-fold increase in CRC risk was observed with a high frequency of meat consumption (OR adjusted for sex and age = 3.4, 95% CI: 1.4-8.1). In the case of GSTT1 gene polymorphism, the increase in risk of CRC was not statistically significant (OR adjusted for sex and age = 1.9, 95% CI: 0.4-8.5). CONCLUSIONS: The frequency of red meat intake in non-smokers increases the risk of colon cancer in the case of GST gene polymorphisms.

Impact of BRAF V600E and TERT Promoter Mutations on Response to Therapy in Papillary Thyroid Cancer.

In this study, we examined the relationship between coexisting BRAF V600E and TERT promoter mutations in papillary thyroid cancer (PTC) and response to therapy. PTC cases (n = 568) with known BRAF and TERT status, diagnosed from 2000 to 2012 and actively monitored at one institution, were reviewed retrospectively. Associations between BRAF V600E and TERT promoter mutations and clinicopathological features, Tumor-Node-Metastasis stage, initial risk, response to therapy, follow-up, and final disease outcome were assessed according to American Thyroid Association 2015 criteria and the American Joint Committee on Cancer/Tumor-Node-Metastasis (8th edition) staging system. Median follow-up was 120 months. TERT promoter mutations (any type) were detected in 13.5% (77/568) of PTC cases with known BRAF status. The C228T and C250T TERT hotspot mutations were found in 54 (9.5%) and 23 (4%) patients, respectively, and 22 other TERT promoter alterations were identified. Coexisting BRAF V600E and TERT hotspot promoter mutations were detected in 9.5% (54/568) of patients, and significantly associated with older patient age (P = 0.001), gross extrathyroidal extension (P = 0.003), tumor stage pT3-4 (P = 0.005), stage II to IV (P = 0.019), intermediate or high initial risk (P = 0.003), worse than excellent response to primary therapy (P = 0.045), recurrence (P = 0.015), and final outcome of no remission (P = 0.014). We conclude that coexisting BRAF V600E and TERT mutations in patients with PTC are associated with poor initial prognostic factors and clinical course and may be useful for predicting a worse response to therapy, recurrence, and poorer outcome than in patients without the above mutations.

Poorly differentiated thyroid cancer in the context of the revised 2015 American Thyroid Association Guidelines and the Updated American Joint Committee on Cancer/Tumor-Node-Metastasis Staging System (eighth edition).

OBJECTIVE: Poorly differentiated thyroid cancer (PDTC) is a rare, but aggressive thyroid cancer (TC) and a main cause of death from non-anaplastic follicular cell-derived TC. Assessing the risk of PDTC-related death and the risk of recurrence is important for clinicians. The recent American Thyroid Association (ATA) 2015 guidelines and the updated 8th edition of the American Joint Committee on Cancer/Tumor-Node-Metastasis (AJCC/TNM) staging system should support clinicians in the management approach to PDTC patients. PATIENTS: Forty-six consecutive PDTC patients treated in a single oncologic centre, 2000-2017. MEASUREMENTS: Retrospective analysis of TNM stage, initial risk, response-to-therapy categories, follow-up and final disease status incorporating the ATA 2015 criteria and the 8th AJCC/TNM staging system. Disease-specific survival (DSS) using the Kaplan-Meier method. RESULTS: Of the 46 PDTC 21 (45.6%) were ATA high risk (HR), 22 (47.8%), 17 (37%) and seven (15.2%) were TNM stages I, II, and III-IV, respectively. During a median follow-up of 55.5 months, two (4.3%) patients were recurrent, 18 (39.1%) died of PDTC. The 5-/10-year DSS were 65/57%, respectively. According to the AJCC/TNM, the 5-/10-year DSS of I, II, and III-IV stage were 83/83%; 77/55%, and 0/0%, respectively. According to the 2015 ATA initial risk, the 5-/10-year DSS were 91/72% for ATA intermediate risk and 38/38% for ATA HR patients. CONCLUSIONS: In PDTC patients, the updated AJCC/TNM staging system accurately predicts a high risk of death in stage III-IV, whereas it seems to be inadequate for predicting a very low or low risk of death expected for differentiated TC in stage I-II. The ATA initial HR may be also used to predict a high risk of PDTC-related death.

Tumor Digital Masking Allows Precise Patient Triaging: A Study Based on Ki-67 Scoring in Gastrointestinal Stromal Tumors.

BACKGROUND: Technological advances constantly provide cutting-edge tools that enhance the progress of diagnostic capabilities. Gastrointestinal stromal tumors belong to a family of mesenchymal tumors where patient triaging is still based on traditional criteria such as mitotic count, tumor size, and tumor location. Limitations of the human eye and randomness in choice of area for mitotic figure counting compel us to seek more objective solutions such as digital image analysis. Presently, the labelling of proliferative activity is becoming a routine task amidst many cancers. The purpose of the present study was to compare the traditional method of prediction based on mitotic ratio with digital image analysis of cell cycle-dependent proteins. METHODS: Fifty-seven eligible cases were enrolled. Furthermore, a digital analysis of previously performed whole tissue section immunohistochemical assays was executed. Digital labelling covered both hotspots and not-hotspots equally. RESULTS: We noted a significant diversity of proliferative activities, and consequently, the results pointed to 6.5% of Ki-67, counted in hotspots, as the optimal cut-off for low-high-grade GIST. ROC analysis (AUC = 0.913; 95% CI: 0.828-0.997, p < 0.00001) and odds ratio (OR = 40.0, 95% CI: 6.7-237.3, p < 0.0001) pointed to Ki-67 16% as the cut-off for very high-grade (groups 5-6) cases. With help of a tumor digital map, we revealed possible errors resulting from a wrong choice of field for analysis. We confirmed that Ki-67 scores are in line with the level of intracellular metabolism that could be used as the additional biomarker. CONCLUSIONS: Tumor digital masking is very promising solution for repeatable and objective labelling. Software adjustments of nuclear shape, outlines, size, etc. are helpful to omit other Ki-67-positive cells especially small lymphocytes. Our results pointed to Ki-67 as a good biomarker in GIST, but concurrently, we noted significant differences in used digital approaches which could lead to unequivocal results.

GSTM1, GSTT1, and GSTP1 polymorphisms and colorectal cancer risk in Polish nonsmokers.

Glutathione S-transferase (GST) enzymes are responsible for cellular detoxification of many carcinogens and are important anticancer elements. This study assessed potential relationships between GSTM1, GSTT1, and GSTP1 polymorphisms and colorectal cancer (CRC) risk in Polish nonsmokers. We also analyzed the influence of GST gene polymorphisms on CRC clinical and histopathological features. Our study included 197 CRC patients and 104 healthy controls. GSTM1, GSTT1, and GSTP1 polymorphisms were evaluated using qPCR. Polymorphism frequencies observed in our control group corresponded to those in other European populations. The GSTM1 null and GSTT1 null genotypes were observed with similar frequencies in both CRC patients and controls (GSTM1 null: 46.7% vs. 45.2%; GSTT1 null: 15.7% vs. 20.2%). GSTP1 Ile/Ile, Ile/Val, and Val/Val genotype frequencies were respectively 42.1%, 48.2%, and 9.6% in patients and 48.1%, 42.3%, and 9.6% in controls. GSTT1 polymorphism correlated with higher tumor grade in CRC patients, and the GSTM1 null/null genotype was associated with more frequent metastasis to lymph nodes (pN classification). Our results suggest that GST gene polymorphisms may influence CRC tumor grade and stage.

Immunohistochemistry cannot replace DNA analysis for evaluation of BRAF V600E mutations in papillary thyroid carcinoma.

INTRODUCTION: The BRAF V600E mutation is the most common genetic event occurring in papillary thyroid cancer (PTC). Recently, the possibility of using immunohistochemistry (IHC) to detect the BRAF V600E mutation has been reported. MATERIALS AND METHODS: In 140 patients with classical PTC, the status of the BRAF V600E mutation was determined by IHC (using two alternative staining protocols, IHC-1 and IHC-2) and molecular biology methods: Sanger sequencing (SEQ) and real-time PCR (qPCR). RESULTS: The BRAF V600E mutation was detected in 57.1% (80/140) patients by IHC-1 and 62.9% (88/140) patients by IHC-2. The highest correlation in detecting the BRAF V600E mutation was found between IHC-2 and qPCR (94.2%), and between IHC-1 and qPCR (83.9%). Correlations between IHC-1 and SEQ and between IHC-2 and SEQ were 71.5% and 76.2%, respectively. The IHC-2 protocol had higher sensitivity, PPV, and NPV, and Cohen's kappa than IHC- 1. The presence of BRAF V600E mutation in IHC-2 statistically correlated with age at diagnosis, histopathological stage, and extrathyroidal extension. CONCLUSIONS: The results obtained in this study indicate a lack of concordance between BRAF V600E detection by IHC and molecular methods. The IHC method cannot replace molecular methods for the detection of the BRAF V600E mutation.

Response to therapy of papillary thyroid cancer of known BRAF status.

OBJECTIVE: A dynamic risk stratification with modified initial estimated risk based on response to therapy and disease course is one of the crucial changes adopted recently by the American Thyroid Association (ATA). This approach focuses on an individualized risk-adapted approach to the management of differentiated thyroid cancer. The BRAF V600E mutation is the most common genetic alteration in papillary thyroid cancer (PTC). However, the prognostic value of this mutation remains unclear. The aim of this study was to examine the relation between the BRAF V600E status in PTC and all ATA response-to-therapy categories, as well as the recurrence and persistence of both biochemical disease and structural disease. PATIENTS: Unselected PTC cases with known BRAF status diagnosed from 2000 to 2013 and actively monitored at one institution (n=723) were reviewed retrospectively. The association between the BRAF V600E mutation and clinicopathological characteristics, ATA 2015 response-to-therapy category, recurrence after a period of no evidence of disease (NED) and persistent biochemical or structural disease, was analysed. RESULTS: BRAF V600E was found in 65.7% (475/723) of PTC cases. Although BRAF mutation status correlated significantly with certain clinicopathological prognostic factors, there was no correlation with any of the response-to-therapy categories. Recurrences and persistent biochemical or structural disease were not associated with BRAF status. CONCLUSIONS: Our data are consistent with those of other studies reporting a positive relation between BRAF V600E mutation and poor prognostic factors in PTC; however, the BRAF status did not significantly correlate with a response to therapy.

Evaluation of molecular diagnostic approaches for the detection of BRAF p.V600E mutations in papillary thyroid cancer: Clinical implications.

Differentiated papillary thyroid cancer (PTC) is the most common cancer of the endocrine system. PTC has a very good prognosis and a high 5 year survival rate; however, some patients are unresponsive to treatment, and their diagnosis eventually results in death. Recent efforts have focused on searching for prognostic and predictive factors that may enable treatment personalization and monitoring across the course of the disease. The presence of the BRAF mutation is considered to contribute to the risk of poor clinical course, according to American Thyroid Association (ATA) recommendations. The method used for genotyping can impact the predicted mutation frequency; however, ATA recommendations do not address this issue. We evaluated the molecular diagnostic (BRAF p.V600E mutation) results of 410 patients treated for PTC. We thoroughly analyzed the impact of three different BRAF mutation detection methods, Sanger Sequencing (Seq), allele-specific amplification PCR (ASA-PCR), and quantitative PCR (qPCR), on the frequency of mutation detection in 399 patients. Using Seq, we detected the BRAF mutation in 37% of patients; however, we were able to detect BRAF mutations in 57% and 60% of patients using the more sensitive ASA-PCR and qPCR technologies, respectively. Differences between methods were particularly marked in the thyroid papillary microcarcinoma group; BRAF p.V600E mutations were found in 37% of patients using Seq and 63% and 66% of patients using ASA-PCR and qPCR, respectively. We also evaluated how these different diagnostic methods were impacted by DNA quality. Applying methods with different sensitivities to the detection of BRAF p.V600E mutations may result in different results for the same patient; such data can influence stratification of patients into different risk groups, leading to alteration of treatment and follow-up schemes.

Conventional colon adenomas harbor various disturbances in microsatellite stability and contain micro-serrated foci with microsatellite instability.

INTRODUCTION: Colorectal cancer belongs to the most frequent occurring malignancies. A prediction of the clinical outcome and appropriate choice of neoadjuvant chemotherapy needs personalized insight to the main driving pathways. Because most CRCs have polyps as progenitor lesions, studying the pathways driving to adenomagenesis is no less important. GOALS: Our purpose was the evaluation of microsatellite stability status within conventional colon adenomas and also ß-catenin, BRAFV600E and p53 contribution. MATERIAL AND METHODS: The cohort included 101 cases of typical colon adenomas with high grade epithelial dysplasia according to WHO. An immunohistochemistry method was used for the depiction of the expression of targeted proteins, as also their heterogeneity. RESULTS: Generally, we noted a 10% frequency of MSI events where MSI-H reached a 5% share occurred within the left colon and rectal polyps. ß-catenin nuclear overexpression was noted with a 70% frequency and p53 with close to a 24% frequency. In addition, we found a presence of micro-serration foci more often within tubular adenomas, where focal MSI took place more often. Our results indicate that MSI events occur more often than had been theorized earlier. It results in tumour heterogeneity, more complex underlying pathways and finally ontogenetic molecular-diversity of tumours besides similar occurring histopathological features.