Autoimmunity, cancer and COVID-19 abnormally activate wound healing pathways: critical role of inflammation.

Recent evidence indicates that targeting IL-6 provides broad therapeutic approaches to several diseases. In patients with cancer, autoimmune diseases, severe respiratory infections [e.g. coronavirus disease 2019 (COVID-19)] and wound healing, IL-6 plays a critical role in modulating the systemic and local microenvironment. Elevated serum levels of IL-6 interfere with the systemic immune response and are associated with disease progression and prognosis. As already noted, monoclonal antibodies blocking either IL-6 or binding of IL-6 to receptors have been used/tested successfully in the treatment of rheumatoid arthritis, many cancer types, and COVID-19. Therefore, in the present review, we compare the impact of IL-6 and anti-IL-6 therapy to demonstrate common (pathological) features of the studied diseases such as formation of granulation tissue with the presence of myofibroblasts and deposition of new extracellular matrix. We also discuss abnormal activation of other wound-healing-related pathways that have been implicated in autoimmune disorders, cancer or COVID-19.

Pitx2 is a useful marker of midgut-derived neuroendocrine tumours - an immunohistochemical study of 224 cases.

Pitx2 is a transcription factor responsible for establishment of the right-left axis and development of the gut and pituitary. In mouse embryos, Pitx2 is expressed in the greater curvature of the stomach and midgut. Previously, Pitx2 was studied in pituitary neuroendocrine tumours but not in other NETs. Pitx2 expression was immunohistochemically assessed in whole sections and tissue microarrays in a cohort of 224 neuroendocrine neoplasms, and was analysed in 29 cases. The cohort included 18 cauda equina NETs, 38 paragangliomas, 98 cases of primary visceral NETs from different organs, 23 metastases of visceral NETs and 47 neuroendocrine carcinomas (NECs). Pitx2 expression was observed in 29.5% (29 of 98) NETs and 14.9% (7 of 47) NECs, but was not observed in any paraganglioma or cauda equina NET. Pitx2 was observed only in tumours of midgut-derived organs, including the small intestine (100%, 20 of 20), appendix (88.9%, eight of nine) and large intestine (9.1%, one of 11 - only caecal NET). The NETs of remaining locations were negative. Pitx2 was 96.7% sensitive and 100% specific for NETs of midgut origin. In NECs, Pitx2 positivity was observed in goblet cell adenocarcinoma (75%, three of four), medullary thyroid carcinoma (42.9, three of seven) and one Merkel cell carcinoma (25%, one of four). In metastatic NETs, Pitx2 was observed in all the tumours originating in the small intestine (n = 17) or caecum (n = 1). No positivity was observed in tumours from other locations (four pancreas, one lung). We observed no correlation between immunoreactivity and mRNA expression. Thus, Pitx2 immunohistochemistry can be helpful in assessing the midgut origin of NETs.

Cribriform - morular thyroid carcinoma: a rare entity.

We present a case report of a 51-year-old patient who underwent totalization of thyroidectomy - resection of the right thyroid lobe for growth progression of the largest nodule from which a fine needle aspiration biopsy (FNAB) was performed and was cytologically suspected of malignancy. Nodule was a graywhite colored tumor with a solid structure, histologically with an unusual morphology and immunoprofile, called cribriform morular thyroid carcinoma (CMTC). Usually, the tumor behaves indolently with a good prognosis. CMTC can be familial or sporadic, predominantly as a solitary or a multifocal lesion, often associated with autosomal dominant adenomatous polyposis syndrome (FAP), so it is necessary to point this out in the report. The syndrome of familial adenomatous polyposis was ruled out, the APC gene mutation was somatic.

Predictive and prognostic significance of tumour subtype, SSTR1-5 and e-cadherin expression in a well-defined cohort of patients with acromegaly.

In somatotroph pituitary tumours, somatostatin analogue (SSA) therapy outcomes vary throughout the studies. We performed an analysis of cohort of patients with acromegaly from the Czech registry to identify new prognostic and predictive factors. Clinical data of patients were collected, and complex immunohistochemical assessment of tumour samples was performed (SSTR1-5, dopamine D2 receptor, E-cadherin, AIP). The study included 110 patients. In 31, SSA treatment outcome was evaluated. Sparsely granulated tumours (SGST) differed from the other subtypes in expression of SSTR2A, SSTR3, SSTR5 and E-cadherin and occurred more often in young. No other clinical differences were observed. Trouillas grading system showed association with age, tumour size and SSTR2A expression. Factors significantly associated with SSA treatment outcome included age, IGF1 levels, tumour size and expression of E-cadherin and SSTR2A. In the group of SGST, poor SSA response was observed in younger patients with larger tumours, lower levels of SSTR2A and higher Ki67. We observed no relationship with expression of other proteins including AIP. No predictive value of E-cadherin was observed when tumour subtype was considered. Multiple additional factors apart from SSTR2A expression can predict treatment outcome in patients with acromegaly.

Cytokeratin 8/18-negative somatotroph pituitary neuroendocrine tumours (PitNETs, adenomas) show variable morphological features and do not represent a clinicopathologically distinct entity.

AIMS: In somatotroph pituitary neuroendocrine tumours (adenomas), a pattern of cytokeratin (CK) 18 expression is used for tumour subclassification, with possible clinical implications. Rare somatotroph tumours do not express CK 18. We aimed to characterise this subset clinically and histologically. METHODS AND RESULTS: Clinical and pathological data for the study were derived from a previously published data set of a cohort of 110 patients with acromegaly. Data included serum levels of insulin-like growth factor 1 (IGF1), growth hormone (GH), prolactin and thyroid-stimulating hormone (TSH), tumour diameter, tumour invasion defined by Knosp grade and immunohistochemical data concerning the expression of Ki67, p53, E-cadherin, somatostatin receptor (SSTR)1, SSTR2A, SSTR3, SSTR5 and D2 dopamine receptor. Additional immunohistochemical analysis (AE1/3, CK 8/18, vimentin, neurofilament light chain, internexin-α) was performed. CK 18 was negative in 10 of 110 (9.1%) tumours. One of these tumours was immunoreactive with CK 8/18 antibody, while the remainder expressed only internexin-α intermediate filament in patterns similar to CK 18 (perinuclear fibrous bodies). CK-negative tumours showed no significant differences with respect to biochemical, radiological or pathological features. They showed significantly higher expression of SSTR2A compared to the sparsely granulated subtype and significantly lower expression of E-cadherin compared to the non-sparsely granulated subtypes of tumours. The tumours showed divergent morphology and hormonal expression: two corresponded to densely granulated tumours and three showed co-expression of prolactin and morphology of either mammosomatotroph or somatotroph-lactotroph tumours. Four tumours showed morphology and immunoprofile compatible with plurihormonal Pit1-positive tumours. CONCLUSIONS: CK-negative somatotroph tumours do not represent a distinct subtype of somatotroph tumours, and can be further subdivided according to their morphology and immunoprofile.

Molecular testing in endometrial carcinoma - joint recommendation of Czech Oncological Society, Oncogynecological Section of the Czech Gynecological and Obstetrical Society, Society of Radiation Oncology, Biology and Physics, and the Society of Czech Pathologists.

Molecular classification of endometrial carcinoma is becoming an important part of the dia-gnostic process with direct therapeutic implications. Recent international guidelines, including the joint recommendation of the European Society of Gynaecological Oncology, the European Society for Radiotherapy and Oncology and the European Society of Pathology include the molecular classification into standard dia-gnostic algorithms. Molecular testing of endometrial carcinomas is also recommended in the latest (5th edition) of the World Health Organization classification of female genital tumors. Due to the need to implement these recommendations in practice, representatives of four professional societies of the Czech Medical Association of J. E. Purkyně (the Czech Oncological Society, the Oncogynecological Section of the Czech Gynecological and Obstetrical Society, the Society of Radiation Oncology, Biology and Physics, and the Society of Czech Pathologists) organized a meeting focused on this topic. Recommendation for molecular testing of endometrial carcinoma in routine dia-gnostic practice in the Czech Republic.

The possibilities of molecular testing of somatic aberrations in tumor tissue using NGS in routine practice - current situation in the Czech Republic.

Molecular testing of tumor tissue for the detection of somatic aberrations using NGS is increasingly gaining significance in routine practice. The technical aspects of testing are standardized and currently do not pose a problem. However, the situation is evolving very rapidly regarding the indication of testing, which depends on the sometimes rapidly developing medical knowledge and needs in clinical practice. In order to implement NGS testing in practice and arrange its reimbursement by the health care system, first it is necessary to reach an agreement on the level of professional societies concerning the definition of priority and medically clearly justified areas in which molecular testing has a clear impact on therapeutical choices. The next step is to reach an agreement with the health insurance companies regarding NGS testing. The aim of this article is to provide an overview of the issue of routine tumor tissue testing using the NGS method covered by public health insurance, with a summary of the current situation in the Czech Republic. Only the testing of somatic aberrations in solid tumors performed at pathology departments is discussed. The issue of testing in haemato-oncological centres is not the subject of this review.

Review of tumor infiltrating lymphocytes assessment in breast cancer in routine diagnostic practice.

Evaluation of tumor infiltrating lymphocytes (TIL) is gaining importance in many cancers not only because of their prognostic, but also predictive significance. One of the tumors in which the evaluation of TIL is of prognostic importance and has potential predictive impact on the modification of treatment procedures is breast cancer, especially its so-called triple negative, and HER2 positive variants.The aim of this review is to provide an overview of the issue of TIL evaluation in breast cancer, focusing not only on the clinical significance of this evaluation, but especially on the methodological aspects of evaluation and standardized reporting of the results.

Molecular testing in endometrial carcinoma (Joint recommendation of Czech Oncological Society, Oncogynecological Section of the Czech Gynecological and Obstetrical Society, Society of Radiation Oncology, Biology and Physics, and the Society of Czech Pathologists).

Molecular classification of endometrial carcinoma is becoming an important part of the diagnostic process with direct therapeutic implications. Recent international guidelines, including the joint ESGO-ESTRO-ESP recommendation, include the molecular classification into standard diagnostic algorithms. Molecular testing of endometrial carcinomas is also recommended in the latest (5th) edition of the WHO classification of Female Genital Tumors. Due to the need to implement these recommendations in practice, representatives of four professional societies of Czech Medical Association of J. E. Purkyně (Czech Oncological Society, Oncogynecological Section of the Czech Gynecological and Obstetrical Society, Society of Radiation Oncology, Biology and Physics, and the Society of Czech Pathologists) organized a meeting focused on this topic. The result of this meeting is a joint recommendation for molecular testing of endometrial carcinoma in routine diagnostic practice in the Czech Republic.

Prognostic value of histopathological DCIS features in a large-scale international interrater reliability study.

PURPOSE: For optimal management of ductal carcinoma in situ (DCIS), reproducible histopathological assessment is essential to distinguish low-risk from high-risk DCIS. Therefore, we analyzed interrater reliability of histopathological DCIS features and assessed their associations with subsequent ipsilateral invasive breast cancer (iIBC) risk. METHODS: Using a case-cohort design, reliability was assessed in a population-based, nationwide cohort of 2767 women with screen-detected DCIS diagnosed between 1993 and 2004, treated by breast-conserving surgery with/without radiotherapy (BCS ± RT) using Krippendorff's alpha (KA) and Gwet's AC2 (GAC2). Thirty-eight raters scored histopathological DCIS features including grade (2-tiered and 3-tiered), growth pattern, mitotic activity, periductal fibrosis, and lymphocytic infiltrate in 342 women. Using majority opinion-based scores for each feature, their association with subsequent iIBC risk was assessed using Cox regression. RESULTS: Interrater reliability of grade using various classifications was fair to moderate, and only substantial for grade 1 versus 2 + 3 when using GAC2 (0.78). Reliability for growth pattern (KA 0.44, GAC2 0.78), calcifications (KA 0.49, GAC2 0.70) and necrosis (KA 0.47, GAC2 0.70) was moderate using KA and substantial using GAC2; for (type of) periductal fibrosis and lymphocytic infiltrate fair to moderate estimates were found and for mitotic activity reliability was substantial using GAC2 (0.70). Only in patients treated with BCS-RT, high mitotic activity was associated with a higher iIBC risk in univariable analysis (Hazard Ratio (HR) 2.53, 95% Confidence Interval (95% CI) 1.05-6.11); grade 3 versus 1 + 2 (HR 2.64, 95% CI 1.35-5.14) and a cribriform/solid versus flat epithelial atypia/clinging/(micro)papillary growth pattern (HR 3.70, 95% CI 1.34-10.23) were independently associated with a higher iIBC risk. CONCLUSIONS: Using majority opinion-based scores, DCIS grade, growth pattern, and mitotic activity are associated with iIBC risk in patients treated with BCS-RT, but interrater variability is substantial. Semi-quantitative grading, incorporating and separately evaluating nuclear pleomorphism, growth pattern, and mitotic activity, may improve the reliability and prognostic value of these features.

Sensitive detection methods are key to identify secondary EGFR c.2369C>T p.(Thr790Met) in non-small cell lung cancer tissue samples.

BACKGROUND: Correct identification of the EGFR c.2369C>T p.(Thr790Met) variant is key to decide on a targeted therapeutic strategy for patients with acquired EGFR TKI resistance in non-small cell lung cancer. The aim of this study was to evaluate the correct detection of this variant in 12 tumor tissue specimens tested by 324 laboratories participating in External Quality Assessment (EQA) schemes. METHODS: Data from EQA schemes were evaluated between 2013 and 2018 from cell lines (6) and resections (6) containing the EGFR c.2369C>T p.(Thr790Met) mutation. Adequate performance was defined as the percentage of tests for which an outcome was available and correct. Additional data on the used test method were collected from the participants. Chi-squared tests on contingency tables and a biserial rank correlation were applied by IBM SPSS Statistics version 25 (IBM, Armonk, NY, USA). RESULTS: In 26 of the 1190 tests (2.2%) a technical failure occurred. For the remaining 1164 results, 1008 (86.6%) were correct, 151 (12.9%) were false-negative and 5 (0.4%) included incorrect mutations. Correct p.(Thr790Met) detection improved over time and for repeated scheme participations. In-house non-next-generation sequencing (NGS) techniques performed worse (81.1%, n = 293) compared to non-NGS commercial kits (85.2%, n = 656) and NGS (97.0%, n = 239). Over time there was an increase in the users of NGS. Resection specimens performed worse (82.6%, n = 610 tests) compared to cell line material (90.9%, n = 578 tests), except for NGS (96.3%, n = 344 for resections and 98.6%, n = 312 for cell lines). Samples with multiple mutations were more difficult compared to samples with the single p.(Thr790Met) variant. A change of the test method was shown beneficial to reduce errors but introduced additional analysis failures. CONCLUSIONS: A significant number of laboratories that offer p.(Thr790Met) testing did not detect this relevant mutation compared to the other EQA participants. However, correct identification of this variant is improving over time and was higher for NGS users. Revising the methodology might be useful to resolve errors, especially for resection specimens with low frequency or multiple variants. EQA providers should include challenging resections in the scheme.

Neoplastic cell percentage estimation in tissue samples for molecular oncology: recommendations from a modified Delphi study.

AIMS: Results from external quality assessment revealed considerable variation in neoplastic cell percentages (NCP) estimation in samples for biomarker testing. As molecular biology tests require a minimal NCP, overestimations may lead to false negative test results. We aimed to develop recommendations to improve the NCP determination in a prototypical entity - colorectal carcinoma - that can be adapted for other cancer types. METHODS AND RESULTS: A modified Delphi study was conducted to reach consensus by 10 pathologists from 10 countries with experience in determining the NCP for colorectal adenocarcinoma. This study included two online surveys and a decision-making meeting. Consensus was defined a priori as an agreement of > 80%. All pathologists completed both surveys. Consensus was reached for 8 out of 19 and 2 out of 13 questions in the first and second surveys, respectively. Remaining issues were resolved during the meeting. Twenty-four recommendations were formulated. Major recommendations resulted as follows: only pathologists should conduct the morphological evaluation; nevertheless molecular biologists/technicians may estimate the NCP, if specific training has been performed and a pathologist is available for feedback. The estimation should be determined in the area with the highest density of viable neoplastic cells and lowest density of inflammatory cells. Other recommendations concerned: the determination protocol itself, needs for micro- and macro-dissection, reporting and interpreting, referral practices and applicability to other cancer types. CONCLUSION: We believe these recommendations may lead to more accurate NCP estimates, ensuring the correct interpretation of test results, and might help in validating digital algorithms in the future.

Use of a new pneumatic system to support capillary microperfusion in surgical wound healing: an animal model.

OBJECTIVE: To test the efficacy of the a developed medical device, based on the principle of mechanical support of capillary microperfusion. METHOD: In this pilot study involving experimental animals, each pig had two standardised surgical wounds. A cuff that delivered pneumatic three-second micropulses was applied to the wound designated as the 'experimental wound'. The pressure inside the cuff was kept at a level <10mmHg so that during the pulse, the pressure would decrease by one third of the established value. The second wound, designated as the 'control wound', was covered with a standard dressing. Over the course of five days, the pressure inside the cuff was monitored. After the five days, the experimental animal was euthanised and two specimens were collected for histological analysis (one sample from each wound site). Wound healing parameters for the experimental and control wounds were examined by a pathologist. The level of statistical significance was set at 0.05. RESULTS: In this study, 10 experimental animals were used. The average pressure in the cuffs was 8.46mmHg (standard deviation: 3.86). No disparities in wound healing were observed in cases of different average pressures in the experimental wound. With respect to wound healing parameters, a statistically significant difference (p<0.05) was found in favour of the experimental wound. The occurrence of histological signs of poor healing was identical in both study wounds. CONCLUSION: The study shows that a device for the support of capillary microperfusion of the surgical wound had a positive effect. It was confirmed that the mechanical support system of capillary microperfusion was safe and reliable.

Potential use of immunohistochemistry for diagnosis precision in historic paraffin blocks.

Authors present an autopsy case report where the immunohistochemical examination of tissues archived as paraffin blocks for more than 60 years enabled to identify the most probable primary origin of disseminated poorly differentiated adenocarcinoma. The potential issues caused by so called antigen decay and limitations of immunohistochemistry in archive material are discussed.

Non-Small Cell Lung Cancer in Countries of Central and Southeastern Europe: Diagnostic Procedures and Treatment Reimbursement Surveyed by the Central European Cooperative Oncology Group.

This article analyzes the availability of different diagnostic procedures of non-small cell lung cancer (NSCLC) and the reimbursement landscape of drugs for NSCLC in countries of central and southeastern Europe (CEE). A survey was conducted by the Central European Cooperative Oncology Group. Results of the survey show that both availability and reimbursement of diagnoses of molecular alterations in NSCLC, the detection of which is essential for therapeutic decisions, varies widely between countries of CEE. Not only is "reflex" testing often substituted by analyses performed only "on demand," but reimbursement of such assessments varies widely between unavailability and payments by the health care system or even pharmaceutical companies. It was concluded that a structured access to testing and reimbursement should be the aim in order to provide patients with appropriate therapeutic options. IMPLICATIONS FOR PRACTICE: This article provides an overview of the limitations in lung cancer treatment in countries of central and southeastern Europe, as well as the reimbursement status of various lung cancer treatment regimens in these countries, which directly impacts treatment options.

Reproducibility and predictive value of scoring stromal tumour infiltrating lymphocytes in triple-negative breast cancer: a multi-institutional study.

BACKGROUND: Several studies have demonstrated a prognostic role for stromal tumour infiltrating lymphocytes (sTILs) in triple-negative breast cancer (TNBC). The reproducibility of scoring sTILs is variable with potentially excellent concordance being achievable using a software tool. We examined agreement between breast pathologists across Europe scoring sTILs on H&E-stained sections without software, an approach that is easily applied in clinical practice. The association between sTILs and response to anthracycline-taxane NACT was also examined. METHODOLOGY: Pathologists from the European Working Group for Breast Screening Pathology scored sTILs in 84 slides from 75 TNBCs using the immune-oncology biomarker working group guidance in two circulations. There were 16 participants in the first and 19 in the second circulation. RESULTS: Moderate agreement was achieved for absolute sTILs scores (intraclass correlation coefficient (ICC) = 0.683, 95% CI 0.601-0.767, p-value < 0.001). Agreement was less when a 25% threshold was used (ICC 0.509, 95% CI 0.416-0.614, p-value < 0.001) and for lymphocyte predominant breast cancer (LPBC) (ICC 0.504, 95% CI 0.412-0.610, p-value < 0.001). Intra-observer agreement was strong for absolute sTIL values (Spearman ρ = 0.727); fair for sTILs ≥ 25% (κ = 0.53) and for LPBC (κ = 0.49), but poor for sTILs as 10% increments (κ = 0.24). Increasing sTILs was significantly associated with an increased likelihood of a pathological complete response (pCR) on multivariable analysis. CONCLUSION: Increasing sTILs in TNBCs improves the likelihood of a pCR. However, inter-observer agreement is such that H&E-based assessment is not sufficiently reproducible for clinical application. Other methodologies should be explored, but may be at the cost of ease of application.

NSCLC molecular testing in Central and Eastern European countries.

BACKGROUND: The introduction of targeted treatments for subsets of non-small cell lung cancer (NSCLC) has highlighted the importance of accurate molecular diagnosis to determine if an actionable genetic alteration is present. Few data are available for Central and Eastern Europe (CEE) on mutation rates, testing rates, and compliance with testing guidelines. METHODS: A questionnaire about molecular testing and NSCLC management was distributed to relevant specialists in nine CEE countries, and pathologists were asked to provide the results of EGFR and ALK testing over a 1-year period. RESULTS: A very high proportion of lung cancer cases are confirmed histologically/cytologically (75-100%), and molecular testing of NSCLC samples has been established in all evaluated CEE countries in 2014. Most countries follow national or international guidelines on which patients to test for EGFR mutations and ALK rearrangements. In most centers at that time, testing was undertaken on request of the clinician rather than on the preferred reflex basis. Immunohistochemistry, followed by fluorescent in situ hybridization confirmation of positive cases, has been widely adopted for ALK testing in the region. Limited reimbursement is a significant barrier to molecular testing in the region and a disincentive to reflex testing. Multidisciplinary tumor boards are established in most of the countries and centers, with 75-100% of cases being discussed at a multidisciplinary tumor board at specialized centers. CONCLUSIONS: Molecular testing is established throughout the CEE region, but improved and unbiased reimbursement remains a major challenge for the future. Increasing the number of patients reviewed by multidisciplinary boards outside of major centers and access to targeted therapy based on the result of molecular testing are other major challenges.

[Predictive diagnosis in breast cancer - Whats new in 2018?] / Prediktivní diagnostika u karcinomu prsu - co je nového pro rok 2018?

Detection of predictive markers in breast carcinoma has undergone significant changes, the most important ones - at least in the context of Czech Republic - are related to the detection of HER2 - detection of both over-expression of oncoprotein HER-2/neu and amplification of the c-erbB-2 gene, respectively. In the Czech Republic, immunohistochemical testing is performed as a method of first choice, followed, if needed, by in situ hybridization. The update of the guidelines published in 2013 decreased the threshold for positive tumor cells from 30% to 10%, shifted the threshold for gene amplification (HER2/CEP17 ratio) from 2.2 to 2.0 and slightly changed criteria for classification of expression as 2+. These changes resulted in relatively significant increase of cases classified as "borderline" or "equivocal", requiring confirmation by in situ hybridization. In order to reduce the risk of false results, the cases diagnosed as positive in small (primary) laboratories, have to be confirmed in one of the large central laboratories. This confirmation of HER2 positivity is required before targeted therapy can be started. HER2 testing is recommended in core-cut biopsies virtually always; it is absolutely essential in patients undergoing neoadjuvant systemic therapy. In patients treated primarily by surgery can be the testing performed either in the core cut biopsy or in the final resection specimen. However, it should be kept in mind that the accuracy of some parameters in the core-cut biopsies may be limited, even in cases not influenced by the neoadjuvant chemotherapy (NACHT). The degree of concordance between results of molecular tests in the core-cut biopsy and resection specimen can achieve only 67 % and the precise concordance of histological typing reaches only 84 %, respectively; the concordance of HER2 expression, on the other hand, reaches more than 90%. In patients with positive HER2 result in core-cut biopsy, it is no longer required to repeat the testing in the resection specimen, whereas in case of HER2 negative core-cut biopsy, it is required to repeat the test from resection specimen to minimize the risk of false negative result. The probability of pathological complete response (pCR) varies in individual breast carcinoma subtypes - it reaches 27-51% in triple-negative and HER2+ cases, while in hormone-dependent tumors, namely in those with low proliferative activity, it is significantly lower. Even within the HER2+ carcinoma subgroup, the probability of pCR varies. HER2+ tumors co-expressing ER and PR have a lower rate of pCR than HER2+ carcinomas without co-expression of hormonal receptors. Carcinomas expressing high-molecular weight keratins (CK14, CK 5/6) with basal phenotype or tumors with mutations of HER2/AKT signal pathway (PI3K, PTEN) have also lower response to treatment and worse prognosis.

Molecular pathology in real time.

With the development of sophisticated individualized therapeutic approaches, the role of pathology in classification of tumors is enormously increasing. The solely morphological characterization of neoplastic process is no more sufficient for qualified decision on optimal therapeutic approach. Thus, morphologic diagnosis must be supplemented by molecular analysis of the lesion with emphasis on the detection of status of certain markers used as predictive factors for targeted therapy. Both intrinsic and acquired types of intratumor heterogeneity have an impact at various moments of cancer diagnostics and therapy. The primary heterogeneity of neoplastic tissue represents a significant problem in patients, where only limited biopsy samples from the primary tumor are available for diagnosis, such as core needle biopsy specimens in breast cancer, transthoracic or endobronchial biopsies in lung cancer, or endoscopic biopsies in gastric cancer. Detection of predictive markers may be influenced by this heterogeneity, and the marker detection may be falsely negative or (less probably) falsely positive. In addition, as these markers are often detected in the tissue samples from primary tumor, the differences between molecular features of the primary lesion and its metastases may be responsible for failure of systemic therapy in patients with discordant phenotype between primary and metastatic disease. The fact of tumor heterogeneity must be taken into consideration already in establishing pathological diagnosis. One has to be aware that limited biopsy specimen must not always be fully representative of the entire tumor volume. To overcome these limitations, there does not exist one single simple solution. Examination of more tissue (preference of surgical resection specimens over biopsies, whenever possible), use of ultra-sensitive methods able to identify the minute subclones as a source of possible resistance to treatment, and detection of secondary molecular events from the circulating tumor cells or circulating cell-free DNA are potential solutions how to handle this issue.

Thyroid transcription factor 1 expression is associated with outcome of patients with non-squamous non-small cell lung cancer treated with pemetrexed-based chemotherapy.

Pemetrexed is an antifolate cytostatic agent targeting several folate-dependent enzymatic pathways, widely used in the treatment of locally advanced or metastatic stage non-small cell lung cancer. Aside from the non-squamous histology, there is still no available molecular biomarker predicting treatment efficacy of pemetrexed-based chemotherapy. The aim of our retrospective study was to evaluate the association of thyroid transcription factor 1 expression with outcome of a large cohort of patients with non-squamous non-small cell lung cancer treated with pemetrexed. We retrospectively analysed clinical data of 463 patients with advanced-stage non-small cell lung cancer (IIIB or IV) treated with pemetrexed-based chemotherapy. Thyroid transcription factor 1 expression was assessed using indirect immunohistochemical detection in formalin-fixed paraffin-embedded tumour tissue at the time of diagnosis. Thyroid transcription factor 1 expression was detected in the tumour tissue from 76.0% of patients, and tumours from 24.0% of patients were thyroid transcription factor 1 negative. The median progression-free survival and overall survival for patients with thyroid transcription factor 1 positive tumours were 4.8 and 11.8 months compared to 2.8 and 8.3 months for those with thyroid transcription factor 1 negative tumours (p = 0.001 and p < 0.001). The multivariable Cox proportional hazards model revealed that thyroid transcription factor 1 expression was significantly associated with progression-free survival (hazard ratio = 1.57, p < 0.001) and also with overall survival (hazard ratio = 1.73, p < 0.001). In conclusion, the results of the conducted retrospective study suggest that the thyroid transcription factor 1 expression was independently associated with progression-free survival and overall survival in patients with advanced-stage non-squamous non-small cell lung cancer treated with pemetrexed-based chemotherapy.