Cribriform morular thyroid carcinoma: Clinicopathological and molecular basis for both a preventive and therapeutic approach for a rare tumor (Review).

Cribriform morular thyroid carcinoma (CMTC) has been included within the group of thyroid tumors of uncertain histogenesis in the recent World Health Organization classification of endocrine tumors. Most CMTCs occur in young euthyroid women with multiple (and bilateral) thyroid nodules in cases associated with familial adenomatous polyposis (FAP) or as single nodules in sporadic cases. CMTC generally behaves indolently, while aggressiveness and mortality are associated with high­grade CMTC. This tumor histologically displays a distinctive combination of growth patterns with morular structures. Strong diffuse nuclear and cytoplasmic immunostaining for ß­catenin is the hallmark of CMTC. Tumor cells are also positive for thyroid transcription factor­1 and for estrogen and progesterone receptors, but negative for thyroglobulin and calcitonin. It is possible that the CMTC phenotype could result from blockage in the terminal/follicular differentiation of follicular cells (or their precursor cells) secondary to the permanent activation of the Wnt/ß­catenin pathway. In CMTC, the activation of the Wnt/ß­catenin pathway is the central pathogenetic event, which in FAP­associated cases results from germline mutations of the APC regulator of WNT signaling pathway (APC) gene, and in sporadic cases from somatic inactivating mutations in the APC, AXIN1 and CTNNB1 genes. Estrogens appear to play a tumor­promoting role by stimulating both the PI3K/AKT/mTOR and the RAS/RAF/MAPK signaling pathways. Additional somatic mutations (i.e. RET rearrangements, or KRAS, phosphatidylinositol­4,5­bisphosphate 3­kinase catalytic subunit α, telomerase reverse transcriptase or tumor protein 53 mutations) may further potentiate the development and progression of CMTC. While hemithyroidectomy would be the treatment of choice for sporadic cases without high­risk data, total thyroidectomy would be indicated in FAP­associated cases. There is insufficient clinical data to propose therapies targeting the Wnt/ß­catenin pathway, but multikinase or selective inhibitors could be used in a manner analogous to that of conventional thyroid tumors. It is also unknown whether adjuvant antiestrogenic therapy could be useful in the subgroup of women undergoing surgery with high­risk CMTC, as well as when there is tumor recurrence and/or metastasis.

Cribriform morular thyroid carcinoma: a case report with pathological, immunohistochemical, and molecular findings suggesting an origin from follicular cells (or their endodermal precursors).

Cribriform morular thyroid carcinoma (CMTC) is a rare malignant thyroid tumor with a peculiar growth pattern secondary to permanent activation of the WNT/ß-catenin pathway. CMTC may be associated with familial adenomatous polyposis or sporadic; it shares morphological features with papillary thyroid carcinoma (PTC) and was considered a variant of PTC in the 2017 WHO classification of tumors of endocrine organs. The new 5th edition of the WHO classification of endocrine and neuroendocrine tumors considered CMTC an independent thyroid neoplasm of uncertain histogenesis. A thymic/ultimobranchial pouch-related differentiation in CMTC has been recently postulated. We, however, have used the pathological and immunohistochemical features of this case of CMTC with 2 novel oncogenic somatic variants (c.3428_3429insA, p.(Tyr1143Ter) and c.3565del, p. (Ser1189Hisfs*76) of the APC gene to propose an origin from follicular cells (or their endodermal precursors). As usual in CMTC, the morular component of this tumor was positive for CDX2. Given the fact that WNT/ß-catenin signaling, through CDX2, activates large intestine and small intestine gene expression, we postulate that in CMTC, the tumor cells have their terminal differentiation blocked, thus showing a peculiar primitive endodermal (intestinal-like) phenotype negative for sodium-iodide symporter, thyroperoxidase, and thyroglobulin. Establishing the histogenesis of CMTC is very relevant for the development of appropriate therapies of redifferentiation, particularly in patients where the tumor cannot be controlled by surgery.

Clinical significance of baseline Pan-Immune-Inflammation Value and its dynamics in metastatic colorectal cancer patients under first-line chemotherapy.

Pan-Immune-Inflammation Value (PIV) has been recently proposed as a new blood-based prognostic biomarker in metastatic colorectal cancer (mCRC). Herein we aimed to validate its prognostic significance and to evaluate its utility for disease monitoring in patients with mCRC receiving first-line chemotherapy. We conducted a single-centre retrospective study involving 130 previously untreated mCRC patients under first-line standard chemotherapy in a real-world scenario. PIV was calculated as (neutrophil count × platelet count × monocyte count)/lymphocyte count at three different time-points: baseline, week 4 after therapy initiation, and at disease progression. We analyzed the influence of baseline PIV on overall survival (OS), progression-free survival (PFS), disease control rate (DCR), and overall response rate (ORR). We also explored the utility of PIV dynamics for disease monitoring. Baseline PIV high was significantly associated with worse OS in univariate [hazard ratio (HR) = 2.10, 95% CI, 1.41-3.15; p = 0.000299] and multivariate (HR = 1.82, 95% CI, 1.15-2.90; p = 0.011) analyses. Baseline PIV was also associated with worse PFS in univariate (HR = 2.04, 95% CI, 1.40-2.97; p = 0.000187) and multivariate (HR = 1.56, 95% CI, 1.05-2.31; p = 0.026) analyses. Baseline PIV was not correlated either with DCR or ORR. Regarding PIV dynamics, there was a statistically significant increase from week 4 to disease progression (p = 0.0003), which was at the expense of cases with disease control as best response (p < 0.0001). In conclusion, this study validates the prognostic significance of baseline PIV in patients with mCRC receiving first-line standard chemotherapy in a real-world scenario. Moreover, it suggests the potential utility of PIV monitoring to anticipate the disease progression among those patients who achieve initial disease control.

Susceptibility Genes and Chromosomal Regions Associated With Non-Syndromic Familial Non-Medullary Thyroid Carcinoma: Some Pathogenetic and Diagnostic Keys.

Thyroid cancer is the malignant tumor that is increasing most rapidly in the world, mainly at the expense of sporadic papillary thyroid carcinoma. The somatic alterations involved in the pathogenesis of sporadic follicular cell derived tumors are well recognized, while the predisposing alterations implicated in hereditary follicular tumors are less well known. Since the genetic background of syndromic familial non-medullary carcinoma has been well established, here we review the pathogenesis of non-syndromic familial non-medullary carcinoma emphasizing those aspects that may be useful in clinical and pathological diagnosis. Non-syndromic familial non-medullary carcinoma has a complex and heterogeneous genetic basis involving several genes and loci with a monogenic or polygenic inheritance model. Most cases are papillary thyroid carcinoma (classic and follicular variant), usually accompanied by benign thyroid nodules (follicular thyroid adenoma and/or multinodular goiter). The possible diagnostic and prognostic usefulness of the changes in the expression and/or translocation of various proteins secondary to several mutations reported in this setting requires further confirmation. Given that non-syndromic familial non-medullary carcinoma and sporadic non-medullary thyroid carcinoma share the same morphology and somatic mutations, the same targeted therapies could be used at present, if necessary, until more specific targeted treatments become available.

Clinical potential of circulating free DNA and circulating tumour cells in patients with metastatic non-small-cell lung cancer treated with pembrolizumab.

Immune checkpoint inhibitors, such as pembrolizumab, are revolutionizing therapeutic strategies for different cancer types, including non-small-cell lung cancer (NSCLC). However, only a subset of patients benefits from this therapy, and new biomarkers are needed to select better candidates. In this study, we explored the value of liquid biopsy analyses, including circulating free DNA (cfDNA) and circulating tumour cells (CTCs), as a prognostic or predictive tool to guide pembrolizumab therapy. For this purpose, a total of 109 blood samples were collected from 50 patients with advanced NSCLC prior to treatment onset and at 6 and 12 weeks after the initiation of pembrolizumab. Plasma cfDNA was measured using hTERT quantitative PCR assay. The CTC levels at baseline were also analysed using two enrichment technologies (CellSearch® and Parsortix systems) to evaluate the efficacy of both approaches at detecting the presence of programmed cell death ligand 1 on CTCs. Notably, patients with high baseline hTERT cfDNA levels had significantly shorter progression-free survival (PFS) and overall survival (OS) than those with low baseline levels. Moreover, patients with unfavourable changes in the hTERT cfDNA levels from baseline to 12 weeks showed a higher risk of disease progression. Additionally, patients in whom CTCs were detected using the CellSearch® system had significantly shorter PFS and OS than patients who had no CTCs. Finally, multivariate regression analyses confirmed the value of the combination of CTCs and cfDNA levels as an early independent predictor of disease progression, identifying a subgroup of patients who were negative for CTCs, who presented low levels of cfDNA and who particularly benefited from the treatment.

PD-L1 expression and immune cells in anaplastic carcinoma and poorly differentiated carcinoma of the human thyroid gland: A retrospective study.

Anaplastic thyroid carcinoma (ATC) and poorly differentiated thyroid carcinoma (PDTC) have limited treatment options, and immune profiling may help select patients for immunotherapy. The prevalence and relevance of programmed death-1 ligand (PD-L1) expression and the presence of immune cells in ATC and PDTC has not yet been well established. The present study investigated PD-L1 expression (clone 22C3) and cells in the tumor microenvironment (TME), including tumor-infiltrating lymphocytes (TILs), tumor-associated macrophages (TAMs) and dendritic cells, in whole tissue sections of 15 cases of ATC and 13 cases of PDTC. Immunohistochemical PD-L1 expression using a tumor proportion score (TPS) with a 1% cut-off was detected in 9/15 (60%) of ATC cases and 1/13 (7.7%) of PDTC cases (P=0.006). PD-L1 expression in TILs was limited to the ATC group (73.3 vs. 0% in ATC and PDTC, respectively). In the ATC group, the TPS for tumor positive PD-L1 expression revealed a non-significant trend towards worse survival, but no difference was observed when investigating PD-L1 expression in TILs and TAMs. In addition to increased PD-L1 expression, all ATC cases exhibited significantly increased CD3+ and CD8+ T cells, CD68+ and CD163+ macrophages, and S100+ dendritic cells compared with the PDTC cases. Loss of mutL homolog 1 and PMS1 homolog 2 expression was observed in one ATC case with the highest PD-L1 expression, as well as in the only PDTC case positive for PD-L1. Notably, the latter was the only PDTC case exhibiting positivity for p53 and a cellular microenvironment similar to ATC. The current results indicated that PD-L1 expression was frequent in ATC, but rare in PDTC. In addition to PD-L1, the present study suggested that microsatellite instability may serve a role in both the TME and the identification of immunotherapy candidates among patients with PDTC.

Thyroid Papillary Microtumor: Validation of the (Updated) Porto Proposal Assessing Sex Hormone Receptor Expression and Mutational BRAF Gene Status.

Given the high incidence and excellent prognosis of many papillary thyroid microcarcinomas, the Porto proposal uses the designation papillary microtumor (PMT) for papillary microcarcinomas (PMCs) without risk factors to minimize overtreatment and patients' stress. To validate Porto proposal criteria, we examined a series of 190 PMC series, also studying sex hormone receptors and BRAF mutation. Our updated Porto proposal (uPp) reclassifies as PMT incidental PMCs found at thyroidectomy lacking the following criteria: (a) detected under the age of 19 years; (b) with multiple tumors measuring >1 cm adding up all diameters; and (c) with aggressive morphologic features (extrathyroidal extension, angioinvasion, tall, and/or hobnail cells). PMCs not fulfilling uPp criteria were considered "true" PMCs. A total of 102 PMCs were subclassified as PMT, 88 as PMC, with no age or sex differences between subgroups. Total thyroidectomy and iodine-131 therapy were significantly more common in PMC. After a median follow-up of 9.6 years, lymph node metastases, distant metastases, and mortality were only found in the PMC subgroup. No subgroup differences were found in calcifications or desmoplasia. Expression of estrogen receptor-α and estrogen receptor-ß, progesterone receptor, and androgen receptor was higher in PMC than in nontumorous thyroid tissue. BRAF mutations were detected in 44.7% of PMC, with no differences between subgroups. In surgical specimens, the uPp is a safe pathology tool to identify those PMC with extremely low malignant potential. This terminology could reduce psychological stress associated with cancer diagnosis, avoid overtreatment, and be incorporated into daily pathologic practice.

Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration in the Diagnosis of Hilar and Mediastinal Lymph Node Metastases of Melanoma.

OBJECTIVE: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive technique for investigating hilar and mediastinal lymphadenopathy. This study reports eleven cases in which EBUS-TBNA was used to assess mediastinal and hilar lymph nodes for the presence of metastatic melanoma. MATERIAL AND METHOD: A retrospective study was performed of all patients who had a history of melanoma and underwent EBUS-TBNA to assess hilar or mediastinal lymphadenopathy for the presence of metastatic melanoma. In seven cases, molecular analysis to detect mutations in the BRAF gene was also used. RESULTS: Eight patients had been diagnosed with malignant melanoma in the past (mean 54.4 months, range 18 to 115 months) while in the other three this tumor was primarily diagnosed in the staging phase. The male-female ratio was 6:5, and the mean age was 60.3 years (range 42 to 88 years). The mean hilar or mediastinal lymph node size detected with computed tomography was 3.0 cm (range 1.1 to 8.1 cm). Eight (72.7%) cases had metastases to the lung associated with metastases in the mediastinal lymph nodes. In four (50%) of these cases, the lung metastasis was solitary. Three (27.3%) cases had metastases in the mediastinal lymph nodes in absence of lung metastases. Metastatic melanoma was diagnosed by cytology and confirmed by cell block study with immunohistochemistry in all cases. BRAF mutations were detected in two (28.6%) of seven cases studied. CONCLUSION: Cytology and tissue samples obtained from EBUS-TBNA are adequate to detect metastatic melanoma and permit in some cases the determination of biomarkers and identify the presence or absence of mutations in the BRAF gene. The procedure is safe, fast, and precise for the staging of melanoma.

Cribriform-morular variant of thyroid carcinoma: a neoplasm with distinctive phenotype associated with the activation of the WNT/ß-catenin pathway.

Cribriform-morular variant of thyroid carcinoma is classically associated with familial adenomatous polyposis but, it can also occur as a sporadic neoplasm. This neoplasm is much more frequently observed in women than in men (ratio of 61:1). In familial adenomatous polyposis patients, tumors are generally multifocal and/or bilateral (multinodular appearance), whereas in the sporadic cases tumors tend to occur as single nodules. The tumors are well delimited, and characteristically show a blending of follicular, cribriform, papillary, trabecular, solid, and morular patterns. Neoplastic cells are tall or cuboidal with the occasional nuclear features of classic papillary thyroid carcinoma. The morules include cells with peculiar nuclear clearing and show positivity for CDX2 and CD10. Angioinvasion and capsular invasion have been described in about 30 and 40% of cases, respectively, with lymph node metastases in less than 10% of patients and distant metastases in 6%. Although this tumor has good prognosis, neuroendocrine and/or poor differentiation have been associated with aggressive behavior. Tumor cells can be focally positive or negative for thyroglobulin, but are always positive for TTF-1, estrogen and progesterone receptors, and negative for calcitonin and cytokeratin 20. Nuclear and cytoplasmic staining for ß-catenin is the hallmark of this tumor type; this feature plays a role in fine needle aspiration biopsy. Cribriform-morular variant of thyroid carcinoma has a peculiar endodermal (intestinal-like) type phenotype, activation of the WNT/ß-catenin signaling pathway, and belongs to the non-BRAF-non-RAS subtype of the molecular classification of thyroid tumors. Elevated expression of estrogen and progesterone receptors and activation of the WNT/ß-catenin pathway may prove useful as putative therapeutic targets in cases that do not respond to conventional therapy. Clinicians should be alerted to the possibility of familial adenomatous polyposis when a diagnosis of cribriform-morular variant of thyroid carcinoma is made. Instead of being considered as a variant of papillary thyroid carcinoma its designation as cribriform-morular thyroid carcinoma seems more appropriate.

Fluorescence in situ hybridization analysis of the ALK gene in 2,045 non-small cell lung cancer patients from North-Western Spain (Galicia).

Identification of anaplastic lymphoma receptor tyrosine kinase (ALK) gene rearrangements is a standard diagnostic test in patients with advanced non-small cell lung cancer (NSCLC). The current study describes the experience of ALK rearrangement detection of a referral center in the public health care system of Galicia in North-Western Spain. The fluorescence in situ hybridization (FISH) patterns of the ALK gene and the clinical and pathological features of these patients are reported. This study is also of interest for comparative purposes due to the relative geographical isolation of the area, which could have contributed to particular genetic features. A total of 2,045 tissue samples from NSCLC patients were collected between October 2010 and July 2015 and tested for ALK rearrangements by FISH. Examination of 1,686 paraffin-embedded tissue specimens and 395 cytological samples (306 cell block preparations and 53 cytological smears) was conducted, and any associations between the FISH results and clinicopathological features were assessed. The rate of successful evaluation was marginally higher in tissue samples than in cytological samples (92.9% vs. 84.1%); this difference was not significant. ALK rearrangements were identified in 82 patients(4%): 65 (79.3%) in tissue specimens, 15 (18.3%) in cell block samples and 2 (2.4%) in cytological smears. This genetic translocation appeared to be associated with a non-smoking history, younger age, female gender, stage IV and adenocarcinoma histological type. The findings demonstrate that ALK evaluation by FISH is feasible in tissue and cytological samples. The clinical and pathological features of the ALK-positive series of patients are similar to those previously reported in the literature.

A novel mutation, outside of the candidate region for diagnosis, in the inverted formin 2 gene can cause focal segmental glomerulosclerosis.

Focal and segmental glomerulosclerosis (FSGS) is a histological pattern that has several etiologies, including genetics. The autosomal dominant form of FSGS is a heterogenic disease caused by mutations within three known genes: α-actinin 4 (ACTN4), canonical transient receptor potential 6 (TRPC6), and the inverted formin 2 (INF2) gene. More recently, INF2 mutations have also been attributed to Charcot-Marie-Tooth neuropathy associated with FSGS. Here we performed direct sequencing, histological characterization, and functional studies in a cohort of families with autosomal dominant FSGS. We detected a novel mutation in exon 6 of the INF2 gene outside of the exon 2-4 candidate region used for rapid diagnosis of autosomal dominant FSGS. This new mutation is predicted to alter a highly conserved amino-acid residue within the 17th α-helix of the diaphanous inhibitory domain of the protein. A long-term follow-up of this family indicated that all patients were diagnosed in adulthood, as opposed to early childhood, and progression to end-stage renal disease was at different times without clinical or electrodiagnostic evidence of neuropathy. Thus, this novel mutation in INF2 linked to nonsyndromic FSGS indicates the necessity for full gene sequencing if no mutation is found in the current rapid-screen region of the gene.