Reproducibility of atypia of undetermined significance/follicular lesion of undetermined significance category using the bethesda system for reporting thyroid cytology when reviewing slides from different institutions: A study of interobserver variability among cytopathologists.

BACKGROUND: The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) offers a six-tiered diagnostic scheme for thyroid Fine Needle Aspiration (FNA): Benign, Atypia of Undetermined Significance/Follicular Lesion of Undetermined Significance (AUS/FLUS), suspicious for follicular neoplasm, suspicious for malignancy, malignant, and unsatisfactory with an aim to standardize diagnostic criteria. Reported rate of AUS/FLUS category in the literature has varied from 3% to 20.5%. METHODS: The aim of this study was to assess interobserver variability among cytopathologists to assess reproducibility of the AUS/FLUS category. Seven cytopathologists brought FNA cases (a mixture of atypical and non-atypical FNA diagnosis) diagnosed using TBSRTC from their respective institutions which were reviewed and diagnosed by the participants. The analysis assessed interobserver variability among 7 cytopathologists and determined characteristics on the slides which were associated with concordance to the institutional diagnosis. RESULTS: Seventy eight of 125 (62.4%) benign cases were classified as benign by the reviewers and 26 (21%) were called AUS/FLUS on review. A third of the AUS/FLUS cases were called benign on review and 28.2% were classified as suspicious for neoplasia/malignancy. Roughly a third each of the suspicious for follicular neoplasm/suspicious for malignancy cases were classified as AUS/FLUS. DISCUSSION: When pathologists from different institutions shared their slides, concordance was high for specimens with adequate cellularity and those that were clearly benign but thresholds varied for the other indeterminate categories. Most definite categorization of the AUS/FLUS category was seen on review. Diagn. Cytopathol. 2017;45:399-405. © 2017 Wiley Periodicals, Inc.

Flat DIN 1 (flat epithelial atypia) on core needle biopsy: 63 cases identified retrospectively among 1,751 core biopsies performed over an 8-year period (1992-1999).

Uniform management of flat DIN 1 (flat epithelial atypia) on core needle biopsy (CNB) concerning surgical excision or clinical follow-up are lacking. In a retrospective review of 1,751 CNB over an 8-year period, we found 63 cases with flat DIN 1 as the most advanced lesion; follow-up was available in 55 cases. Of the 63 patients, 24 had a subsequent biopsy for 15 days to 10 years after the initial CNB, an infiltrating carcinoma was found in nine (14.3%) patients, seven (11.1%) in the ipsilateral, and two (3.2%) in the contralateral breast. Five underwent an excisional biopsy of the ipsilateral breast within less than 3 months of the initial CNB; none had either an invasive or intraepithelial carcinoma. Based on our findings, we consider flat DIN 1 a marker of slightly increased risk for subsequent development of invasive breast carcinoma. When flat DIN 1 is found on CNB as the most advanced lesion after mammographic correlation, an excisional biopsy is not mandatory; however, close follow-up is advised with repeat mammograms for early detection of any clinically occult carcinoma in the vicinity of flat DIN 1 that may have been missed by the CNB.

Tissue microarray-based studies of patients with lymph node negative breast carcinoma show that met expression is associated with worse outcome but is not correlated with epidermal growth factor family receptors.

BACKGROUND: It has been shown that receptor tyrosine kinases (RTKs) predict outcome in patients with breast carcinoma. Although RTKs are a large family, HER-2, epidermal growth factor receptor (EGFR), Met (hepatocyte growth factor receptor), and others all have shown the ability to predict outcome. However, it remains unclear whether these markers are defining the same subpopulation of patients with breast carcinoma. In this study, the authors attempted to determine the correlation between RTKs on the basis of their ability to stratify a population according to outcome. METHODS: The authors used tissue microarray technology to study 324 patients with lymph node negative breast carcinoma who had 20-40 years of follow-up. Expression was assessed using immunohistochemical stains for Met, EFGR, fibroblast growth factor receptor (FGFR), and HER-2. Expression levels were assessed by two observers, and correlations were analyzed. Standard pathology information, including tumor size, nuclear grade, Ki-67 receptor status, and estrogen and progesterone receptor expression levels, also was collected. RESULTS: RTK expression in the study cohort revealed two strong correlations. Specifically, HER-2 and EGFR showed similar expression patterns (P < 0.0001), and Met cytoplasmic domain and FGFR cytoplasmic staining showed similar expression patterns (P < 0.0001), but no correlation was found between the two groups. Of these RTKs, only high levels of Met cytoplasmic domain showed significance as a prognostic marker defining a shortened survival compared with the rest of the population (P = 0.0035; relative risk, 2.04). In the same group of patients, HER-2, hormone receptor status, and other RTK family receptors were not correlated with outcome. In multivariate analysis, only Met cytoplasmic domain and tumor size showed independent predictive value. CONCLUSIONS: The current results indicate that the cytoplasmic domain of Met shows a unique staining pattern and defines a set of patients unique from the set of patients defined by overexpression of HER-2, EGFR, or hormone receptors. Furthermore, this group of patients is associated tightly and independently with worse outcome.

Vulvar basal cell carcinoma: two unusual presentations and review of the literature.

BACKGROUND: Basal cell carcinoma (BCC) of the vulva comprises 2-4% of all vulvar cancers. In general, vulvar BCCs tend to grow at slow rates. Nonetheless, they may be locally invasive and destructive if they are neglected. Eight cases of vulvar BCC metastatic to regional lymph nodes have been documented in the literature. CASES: Two unusual cases of vulvar BCC are presented. Case 1 is an 86-year-old white woman who presented with vulvar BCC metastatic to the femoral head. This is the first report of hematogeneous metastasis of vulvar BCC. The patient was treated with palliative vulvar resection and radiation to the femoral metastasis. At 6 months, she progressed with multiple bony and intraperitoneal metastases and died with disease. Case 2 is vulvar BCC in a 90-year-old African-American woman. She was managed by wide local excision and remains disease free to date. CONCLUSION: Vulvar BCCs are rare tumors with an unclear etiology. They can be aggressive and are capable of causing significant morbidity and occasional mortality if they are neglected or improperly treated. Hematogeneous metastasis at presentation appears to result in rapidly progressive disease. The literature regarding the pathogenesis, biologic behavior, and treatment of vulvar BCC is reviewed.