A Detailed Histologic and Molecular Assessment of the Diffuse Sclerosing Variant of Papillary Thyroid Carcinoma.

Diffuse sclerosing variant papillary thyroid carcinoma (DS-PTC) is characterized clinically by a predilection for children and young adults, bulky neck nodes, and pulmonary metastases. Previous studies have suggested infrequent BRAFV600E mutation but common RET gene rearrangements. Using strict criteria, we studied 43 DS-PTCs (1.9% of unselected PTCs in our unit). Seventy-nine percent harbored pathogenic gene rearrangements involving RET, NTRK3, NTRK1, ALK, or BRAF; with the remainder driven by BRAFV600E mutations. All 10 pediatric cases were all gene rearranged (P = .02). Compared with BRAFV600E-mutated tumors, gene rearrangement was characterized by psammoma bodies involving the entire lobe (P = .038), follicular predominant or mixed follicular architecture (P = .003), pulmonary metastases (24% vs none, P = .04), and absent classical, so-called "BRAF-like" atypia (P = .014). There was no correlation between the presence of gene rearrangement and recurrence-free survival. Features associated with persistent/recurrent disease included pediatric population (P = .030), gene-rearranged tumors (P = .020), microscopic extrathyroidal extension (P = .009), metastases at presentation (P = .007), and stage II disease (P = .015). We conclude that DS-PTC represents 1.9% of papillary thyroid carcinomas and that actionable gene rearrangements are extremely common in DS-PTC. DS-PTC can be divided into 2 distinct molecular subtypes and all BRAFV600E-negative tumors (1.5% of papillary thyroid carcinomas) are driven by potentially actionable oncogenic fusions.

HER2 Immunohistochemistry in Invasive Micropapillary Breast Carcinoma: Complete Assessment of an Incomplete Pattern.

CONTEXT.­: Invasive micropapillary carcinoma (IMPC) is a rare variant of breast carcinoma, composed of avascular morula-like tumor clusters surrounded by stromal spaces, which can affect the HER2 immunohistochemical (IHC) staining pattern. The 2013 American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) HER2 testing guideline suggests moderate to intense but incomplete (basolateral) staining be considered equivocal. OBJECTIVES.­: To perform a detailed assessment of HER2 IHC staining patterns in IMPC. DESIGN.­: Hematoxylin-eosin and HER2 IHC slides were retrospectively reviewed to assess the morphology and HER2 IHC characteristics of IMPC. The 2018 ASCO/CAP guideline was applied. RESULTS.­: The cohort consisted of 187 IMPCs from 181 patients with median age of 58 years. Homogeneous (≥90%) micropapillary component was found in 40% (75 of 187) of cases. Receptor profile was as follows: 75% (140 of 187) ER+ HER2-, 19% (37 of 187) ER+ HER2+, 4% (7 of 187) ER- HER2+, and 2% (3 of 187) ER- HER2-. Of 26 cases with HER2 IHC 3+, 65% (17 of 26) showed a basolateral staining pattern with strong intensity. HER2 fluorescence in situ hybridization (FISH) showed amplification in 26% (17 of 66) of HER2 IHC equivocal cases: 76% (13 of 17) showed basolateral staining pattern and 24% (4 of 17) complete staining, with weak to moderate (2), moderate (14), or moderate to strong (1) intensity. CONCLUSIONS.­: The most frequent staining pattern was basolateral, seen in 49% of cases, including 65% HER2 IHC positive and 76% HER2 IHC equivocal/FISH amplified. If a basolateral pattern and weak to moderate staining is observed in IMPC, alternative testing should be performed to confirm the HER2 status.

BRAF V600E detection in cytological thyroid samples: A key component of the decision tree for surgical treatment of papillary thyroid carcinoma.

BACKGROUND: Whether preoperative knowledge of the BRAF mutation status would help to determine the extent of surgery for thyroid nodules is still under investigation. METHODS: We developed a method to state the V600E mutation before surgery on fine-needle aspiration (FNA) stained smears checked to contain tumor cells. We evaluated the interest of the preoperative assessment of the mutation for surgical strategy of nodules, diagnosed as malignant, suspicious for malignancy or follicular neoplasms. RESULTS: The mutation was found in 81% (79 of 97) malignant, 59% (20 of 34) suspicious nodules, and in none of follicular neoplasms (n = 29). Overall, the mutation was detected in 82% of papillary carcinomas. The sensitivity, specificity, and positive and negative predictive values for the diagnosis of malignancy were 75%, 100%, 100%, and 46%, respectively. CONCLUSION: The preoperative knowledge of the V600E mutation status is fundamental to plan total thyroidectomy with certainty and should be part of the decision tree for the management of thyroid nodules. © 2016 Wiley Periodicals, Inc. Head Neck 38: 1017-1021, 2016.

Quantitative assessment of RASSF1A methylation as a putative molecular marker in papillary thyroid carcinoma.

BACKGROUND: Epigenetic alterations such as DNA methylation are widespread cancer, contributing to tumorigenesis and acting as markers for prognostication. Papillary thyroid cancer (PTC) demonstrates tumor-specific methylation of numerous genes, including RASSF1A. Although the function of RASSF1A in PTC tumorigenesis is still being defined, quantitative evaluation of RASSF1A methylation and its correlation with tumor characteristics has not been performed. METHODS: Analysis of RASSF1A methylation was performed using quantitative polymerase chain reaction after methylation-dependent and -sensitive restriction enzyme digestion in PTC (n = 41) and normal (n = 18) thyroid tissue. Methylation was then evaluated for correlation with tumor size, stage, and multiple histopathologic characteristics. RESULTS: RASSF1A promoter hypermethylation was observed in nearly all PTC cases versus normal thyroid tissue, with mean hypermethylation 4.2 times greater in PTC (P < .05). Hypermethylation was greater in multifocal than unifocal PTC (P < .05). Furthermore, tumor methylation was inversely correlated with extracapsular invasion (P < .05). CONCLUSION: RASSF1A methylation differs in PTC compared with normal thyroid, is associated with multifocality, and is inversely correlated with extracapsular invasion. The ease of evaluating methylation status with minute amounts of DNA suggests a potential role for RASSF1A as a molecular marker for characterization of PTC histopathology.

Insulin-like growth factors I and II receptors in the breast cancer survival disparity among African-American women.

OBJECTIVE: African-American (AA) women with breast cancer are more likely to have advanced disease at diagnosis, higher risk of recurrence and poorer prognosis than Caucasian (CA) women. We have recently shown higher insulin-like growth factor II (IGF-II) expression in paired breast tissue samples from AA women as compared to CA women. IGF-II is a potent mitogen that induces cell proliferation and survival signals through activation of the IGF-I and Insulin receptors (IGF-IR, IR) while IGF-II circulating levels are regulated by cellular uptake through the IGF2 receptor. We hypothesize that differential expression of the IGF1R and IGF2R among AA and CA women potentiates IGF-II mitogenic effects, thus contributing to the health disparity observed between these ethnic groups. DESIGN: We examined IGF-IR and IGF2R mRNA, protein expression and IGF1R phosphorylation in paired breast tissue samples from AA and CA women by Real Time-PCR, Western blot analysis, immunohistochemistry and ELISA techniques. RESULTS: Our results showed significantly increased expression of IGF1R in AA normal tissues as compared to CA normal tissues. IGF1R expression was similar between AA normal and malignant tissues, while IGF1R, IRS-1 and Shc phosphorylation was significantly higher in AA tumor samples. Significantly higher levels of IGF2R were found in CA tumor samples as compared to AA tumor samples. CONCLUSIONS: We conclude that IGF1R and IGF2R differential expression may contribute to the increased risk of malignant transformation in young AA women and to the more aggressive breast cancer phenotype observed among AA breast cancer patients and represent, along with IGF-II, potential therapeutic targets in breast cancer.

Quantitative PCR and HER2 testing in breast cancer: a technical and cost-effectiveness analysis.

We performed a technical and cost-effectiveness analysis of quantitative reverse transcription-polymerase chain reaction (Q-RT-PCR) for the assessment of HER2 in breast cancer. We evaluated 44 frozen and 55 formalin-fixed paraffin-embedded (FFPE) breast carcinoma specimens by Q-RT-PCR, immunohistochemical analysis, and fluorescent in situ hybridization (FISH). Immunohistochemical and FISH analyses were performed on individual slides and on tissue microarray. Costs of techniques were calculated to study 1 case and 10 or 40 cases. Q-RT-PCR provided reliable data in frozen and FFPE specimens, which were significantly correlated. HER2 messenger RNA levels were significantly stratified in agreement with immunohistochemical data (P < .05). There was complete concordance between Q-RT-PCR and immunohistochemical results for negative and strongly positive (3+) cases. The intermediate immunohistochemical group (2+), including FISH+ and FISH- cancers, could also be stratified by Q-RT-PCR. Cost analysis documented the advantage of Q-RT-PCR in all US Food and Drug Administration-approved assays. Our data support the use of Q-RT-PCR for testing breast cancer specimens to select patients for HER2 inhibitory therapy.

Assessment of RET/PTC oncogene activation in thyroid nodules utilizing laser microdissection followed by nested RT-PCR.

Single palpable nodules of the thyroid gland are common in clinical practice; the majority of such lesions are benign. However, noninvasive thyroid nodules that exhibit borderline morphological signs of papillary cancer represent a diagnostic challenge. Rearrangements of the RET oncogene have been proposed as a marker for papillary thyroid cancer. In this chapter, methods for the analysis of the RET oncogene in laser microdissected papillary thyroid cancer tissue are described.

Assessment of microsatellite instability in bladder and thyroid malignancies.

Microsatellite instability (MSI) is an indicator of a defective DNA mismatch repair system (MMR) that results from somatic mutations. The present work has been planned to investigate MSI and its clinical significance in human urinary bladder and thyroid cancers in Indian patients. Tumor tissues of histologically confirmed cases of urinary bladder and thyroid cancers, respectively, were obtained. Clinical data on tumor stage and histopathological grades were recorded. Corresponding matched peripheral blood was taken as a control. Genomic DNA was isolated from the tumor tissues and blood using a standard phenol-chloroform extraction method. Polymerase chain reaction was done to amplify mononucleotide microsatellite markers, BAT-26, BAT-40, TGFbetaRII, IGFIIR, hMSH3, and Bax by using specific primer sequences. For analysis of allelic patterns, the PCR products were run on 8% denaturing Polyacrylamide gel and sizing was done using a pUC18 sequencing ladder. The instability with BAT-26 and BAT-40 was found to be 20% and 45% in urinary bladder and 33% and 19% in thyroid cancers, respectively. However, no instability was observed with the other four-mononucleotide markers in either of the cancers studied. Eighty-three percent of the unstable urinary bladder cancers were found to have a high grade in a superficial group, whereas only 27% MSI+ve were muscle invasive cancers. Forty percent of unstable thyroid lesions were found to be at high risk of developing metastasis. Association of BAT-26 and BAT-40 instabilities with high grade tumors as well as risk tumors may help in choosing a more definite therapy at the outset.

[Familial papillary carcinoma of the thyroid: biogenetic identification and clinical assessment of 4 families]. / Il carcinoma papillifero della tiroide a carattere familiare: determinazioni biogenetiche e valutazioni cliniche su quattro gruppi familiari.

The Authors report 9 patients who were affected by familial papillary carcinoma of thyroid These patients were members of 4 families and they were selected in a general group of 97 patients affected by papillary cancer of the thyroid who underwent surgery from 1991 to 1998. The 9 patients were 1st degree relatives: two sisters, two sisters, two sisters and three brothers. The clinical course was similar in patients whether familiar or sporadic group, but average age in first was 10 yrs lower than in the latter group. Functional cervical dissection was needed only one time by lymphatic metastasis. Observed survival was 100% (follow up 92-16 months) and no specific complication was reported. Thyreoglobulin value was less than normal in every patients. Ret linkage analysis was always performed and no rearrangement was found; in 4 patients APC gene was detected but it was never seen. Case studies are consistent with an autosomal dominant trait that shows an high penetrance if associated with a permissive codominant trait. The authors believe that are necessary further studies on this occurrence. In papillary thyroid cancer familiarity was observed in 9.6%, than authors propose that relatives of thyroid papillary cancer should be underwent to screening.

Assessment of ret/PTC-1 rearrangements in neoplastic thyroid tissue using TaqMan RT-PCR.

Among oncogenes studied in thyroid cancers, a specific activated form of c-ret has been found in a minority of papillary thyroid carcinomas (PTCs). In these tumours, c-ret is activated when by somatic rearrangements, the intracellular domain of RET is juxtaposed with the amino-terminal portion of a different donor gene such as H4, thereby generating a chimeric transcript (ret/PTC-1). The functional effects of c-ret activation and its prognostic implications are currently unclear. This study was undertaken to assess the frequency of RET/PTC-1 expression, any distinctive features of positive tumours to which it might be related, and its prognostic importance. Archival material from 88 thyroid neoplasms [50 PTCs, eight anaplastic carcinomas (ATCs), 25 follicular thyroid carcinomas (FTCs) and five follicular adenomas (FAs)] were analysed for ret/PTC-1 and H4 expression using 5' nuclease assay (TaqMan RT-PCR). RNA from the TPC-1 cell line was included as a positive control for c-ret activation. No FTC or FA displayed activation of ret/PTC-1, though all expressed H4. c-ret activation was found in 24% of PTCs (12 of 50), in 87.5% of ATCs (7 of 8), and in 33% of the combined PTC/ATC group. The frequency of c-ret activation in the aggressive ATC variants noted here suggests that ret/PTC-1-positive PTCs might also have a similar poor prognosis and a follow-up study on this cohort is in progress. Ninety per cent of ret/PTC-1-positive tumours failed to express H4, a phenomenon that has not been described previously and which may have considerable bearing on tumour morphology. A statistically significant proportion (58%) of ret/PTC-1-positive, H4-negative PTCs was associated with chronic inflammatory cell infiltration of the tumour and/or the surrounding thyroid. This association has not been reported previously.

Papillary thyroid carcinoma. Etiology, assessment, and therapy.

Most papillary carcinomas do not cause death or significant morbidity. Current modes of therapy when appropriately applied, appear effective for 80% to 90% of patients. The clinical challenge is to identify the minority of patients who will suffer greatly from tumors to direct appropriately the best therapeutic efforts. New appreciation of histologic subtypes of papillary carcinoma has provided fresh clues to identify cancers with poor prognosis. We look forward to innovative therapies to deal with currently untreatable disease.