Travis Ogilvie

A large-scale study of the ultrawideband microwave dielectric properties of normal, benign and malignant breast tissues obtained from cancer surgeries

The development of microwave breast cancer detection and treatment techniques has been driven by reports of substantial contrast in the dielectric properties of malignant and normal breast tissues. However, definitive knowledge of the dielectric properties of normal and diseased breast tissues at microwave frequencies has been limited by gaps and discrepancies across previously published studies. To address these issues, we conducted a large-scale study to experimentally determine the ultrawideband microwave dielectric properties of a variety of normal, malignant and benign breast tissues, measured from 0.5 to 20 GHz using a precision open-ended coaxial probe. Previously, we reported the dielectric properties of normal breast tissue samples obtained from reduction surgeries. Here, we report the dielectric properties of normal (adipose, glandular and fibroconnective), malignant (invasive and non-invasive ductal and lobular carcinomas) and benign (fibroadenomas and cysts) breast tissue samples obtained from cancer surgeries. We fit a one-pole Cole-Cole model to the complex permittivity data set of each characterized sample. Our analyses show that the contrast in the microwave-frequency dielectric properties between malignant and normal adipose-dominated tissues in the breast is considerable, as large as 10:1, while the contrast in the microwave-frequency dielectric properties between malignant and normal glandular/fibroconnective tissues in the breast is no more than about 10%.

MMR deficiency is common in high-grade endometrioid carcinomas and is associated with an unfavorable outcome

OBJECTIVE To assess the prevalence of MMR deficiency (dMMR) in contemporary reclassified high-grade endometrial carcinomas and correlate dMMR with molecular alterations and patient outcome. METHODS In this study we evaluated the expression of MLH1, MSH2, PMS2 and MSH6 assessed by two different methods in a series of 102 high-grade endometrial carcinomas. The series was comprised of 64 high-grade endometrioid carcinomas (HGEC), 27 serous (ESC), and 11 clear cell (CCC) carcinomas. Absence of expression in any of the proteins was considered dMMR. dMMR was correlated with clinicopathological parameters using a Chi-square test. Univariate and multivariate survival analysis was performed using Kaplan-Meier and Cox regression analyses. RESULTS The overall prevalence of dMMR was 28% (29/102) and was seen in 29/64 (45%) HGEC but not detected in any of the ESC and CCC. Within HGEC, dMMR was associated with loss of ARID1A (p=0.0099), loss of PTEN (p=0.044) and wild-type TP53 (p=0.024) expression. dMMR was associated with increased risk for disease specific death by univariate analysis (p=0.013) among stage III/IV HGEC but not in multivariate analysis (p=0.12). CONCLUSIONS Among high-grade endometrial carcinomas, dMMR is restricted to HGEC and could be used as an adjunct diagnostic tool to refute a diagnosis of ESC. The association with dMMR in HGEC with ARID1A/PTEN alterations, TP53 wild type expression pattern and unfavorable outcome suggests that different oncogenetic pathways within HGEC are present.

The dielectric properties of normal and malignant breast tissue at microwave frequencies: analysis, conclusions, and implications from the wisconsin/calgary study

The clinical efficacy of emerging microwave breast cancer detection and hyperthermia treatment techniques (see [X. Li et al., 2005], [M. Converse et al., 2004] and references therein) depend on the microwave dielectric properties of normal, malignant, and benign breast tissues. Knowledge of these properties has been limited by gaps and discrepancies in previously published small-scale studies reporting the dielectric properties of normal and malignant breast tissues obtained from cancer surgeries [L. Sha et al., 2002]. To address these limitations, we have conducted a large-scale joint study at the Universities of Wisconsin and Calgary to experimentally characterize the wideband dielectric properties at microwave frequencies (from 0.5 to 20 GHz) of freshly excised normal, benign, and malignant breast tissues obtained from breast reduction as well as cancer surgeries. In our presentation, we will highlight the conclusions from all aspects of our completed study. Due to space limitations in this conference paper summary, here we focus on the results of a comparison of the dielectric properties of normal breast tissues obtained from both reduction and cancer surgeries.

Morphologic Reproducibility, Genotyping, and Immunohistochemical Profiling Do Not Support a Category of Seromucinous Carcinoma of the Ovary

The 2014 World Health Organization Classification of Tumors of Female Reproductive Organs endorsed the new category of seromucinous carcinoma, a neoplasm that exhibits morphologic and immunophenotypic overlap with other histotypes of ovarian carcinoma. The goal of this study was to determine whether seromucinous carcinoma was a distinct histotype by assessing its diagnostic reproducibility and comparing its molecular composition to the 5 major histotypes of ovarian carcinoma. Thirty-two tumors diagnosed as seromucinous carcinomas from 2 centers were studied. Eighteen cases were randomly selected for a review set comprising a total of 50 ovarian carcinomas of various histotypes. Morphologic histotype was independently assessed by 4 pathologists. For the 32 seromucinous carcinomas, a histotype-specific immunophenotype was assigned using a diagnostic immunohistochemical panel. Histotype-specific genotype was assigned using a combination of immunohistochemistry and targeted next-generation sequencing for somatic mutations, including genes recurrently mutated in ovarian carcinomas. There was low to modest agreement between pathologists with the reference diagnosis of seromucinous carcinoma, ranging from 39% to 56% for the 4 observers. The immunophenotype was not unique but overlapped predominantly with endometrioid and to a lesser extent with mucinous and low-grade serous carcinoma. Genomic and immunohistochemical alterations were detected in a number of target genes, including KRAS (70%), PIK3CA (37%), PTEN (19%), and ARID1A (16%); no CTNNB1 mutations were identified. Nine cases (30%) harbored concurrent KRAS/PIK3CA mutations. An endometrioid genotype was assigned to 19 cases, a low-grade serous genotype to 9, and a mucinous genotype to 1 and 3 cases were uninformative. Integrating morphology, immunophenotype, and genotyping resulted in reclassifying the seromucinous carcinomas to endometrioid 23/32 (72%), low-grade serous 8/32 (25%), and mucinous 1/32 (3%). The morphologic diagnosis of seromucinous carcinomas is not very reliable and it does not exhibit a distinct immunophenotype or genotype. The molecular features overlap mostly with endometrioid and low-grade serous carcinomas. Our data suggest the category of seromucinous carcinoma be discontinued as ancillary molecular tests can assign cases to one of the major histotypes.

Neurofibroma of the porta hepatis

Neurofibromas are generally well-circumscribed tumors of the nervous system, often found in association with neurofibromatosis 1 (NF1). They uncommonly present as a single sporadic form in the retroperitoneum and in the pancreas. We present a case of a 40-year-old man who presented with a 4- to 5-year history of right upper quadrant pain with associated nausea and vomiting. Medical imaging showed a 3.8 by 3.4-cm mass encasing the hepatic artery and the porta hepatis. Surgical resection was performed, with removal of the gallbladder. The mass was histologically diagnosed as a neurofibroma. At 1 year following his surgery, the patient is doing well.

A case report of an extremely rare and aggressive tumor: primary malignant pericardial mesothelioma

Primary pericardial malignant mesothelioma (PMPM) is extremely rare with an incidence less than 0.0022%. It comprises 0.7% of all mesothelioma cases. To date, approximately 350 cases of pericardial mesothelioma have been reported in the literature. Its typical presentation is insidious, with nonspecific signs and symptoms, and usually results in constrictive pericarditis, cardiac tamponade and congestive heart failure either by a serous effusion or by direct tumorous constriction of the heart. With the exception of several case reports, the outcome is uniformly fatal, and patients typically die within six months of diagnosis. Here we report a 72-year-old Cauca -sian male with persistent pericardial and pleural effusion. He was diagnosed with PMPM after pericardectomy. He had only one cycle of chemotherapy with cisplatin and pemetrexed. He developed acute kidney injury as result of chemotherapy. He died 1 month after diagnosis and 6 months after the first symptoms.

A systematic comparison of three commercial estrogen receptor assays in a single clinical outcome breast cancer cohort

Breast cancers are routinely assessed for estrogen receptor status using immunohistochemical assays to assist in patient prognosis and clinical management. Specific assays vary between laboratories, and several antibodies have been validated and recommended for clinical use. As numerous factors can influence assay performance, many laboratories have opted for ready-to-use assays using automated stainers to improve reproducibility and consistency. Three commonly used autostainer vendors—Dako, Leica, and Ventana—all offer such estrogen receptor assays; however, they have never been directly compared. Here, we present a systematic comparison of three platform-specific estrogen receptor ready-to-use assays using a retrospective, tamoxifen-treated, breast cancer cohort from patients who were treated in Calgary, Alberta, Canada from 1985 to 2000. We found all assays showed good intra-observer agreement. Inter-observer pathological scoring showed some variability: Ventana had the strongest agreement followed closely by Dako, whereas Leica only showed substantial agreement. We also analyzed each estrogen receptor assay with respect to 5-year disease-free survival, and found that all performed similarly in univariate and multivariate models. Determination of measures of test performance found that the Leica assay had a lower negative predictive value than Dako or Ventana, compared with the original ligand-binding assay, while other measures—sensitivity, specificity, positive predictive value, and accuracy—were comparable between the three ready-to-use assays. When comparing against disease-free survival, the difference in negative predictive value between the vendor assays were not as extreme, but Dako and Ventana still performed slightly better than Leica. Despite some discordance, we found that all ready-to-use assays were comparable with or superior to the ligand-binding assay, endorsing their continued use. Our analysis also allowed for exploration of estrogen receptor-negative, progesterone receptor-positive cases, and we discovered that this phenotype was not consistent across the assays, suggesting this might be an artifact.

Evaluation of three commercial progesterone receptor assays in a single tamoxifen-treated breast cancer cohort

Estrogen receptor and progesterone receptor status are routinely assessed using immunohistochemistry assays to assist in patient prognosis and clinical management. Three commonly utilized autostainer vendors—Dako, Leica and Ventana—provide ready-to-use progesterone receptor assays; however, they have never been directly compared in a single breast cancer cohort. We looked at three immunohistochemical progesterone receptor assays, in addition to original ligand-binding assay results, in a single retrospective, tamoxifen-treated breast cancer cohort to investigate inter- and intra-observer agreement, concordance, prognostic ability and measures of test performance. All immunohistochemical assays utilized the manufacturers specified protocols. Five-year disease-free survival was the endpoint of interest, and multivariate models were adjusted for lymph node status, tumor grade, tumor size and human epidermal growth factor 2 status. All assays showed substantial to almost perfect agreement between the three observers (Dako κ=0.69–0.90; Leica κ=0.70–0.89; and Ventana κ=0.78–0.94) and concordance (Dako/Leica κ=0.81; Dako/Ventana κ=0.78; and Leica/Ventana κ=0.82). Univariate survival analyses showed that only the ligand-binding assay, Dako and Ventana assays achieved statistical significance. No statistically significant results were seen in multivariate models, although a strong trend was seen with the Ventana progesterone receptor assay. All assays performed similarly with regards to measures of test performance with ligand-binding assay set as the reference, and all immunohistochemical assays outperformed the ligand-binding assay in regards to 5-year disease-free survival. Despite similar agreement and concordance with the progesterone receptor assays, clear differences were noted with regards to 5-year disease-free survival. Additional survival analyses suggest that clinical utility of estrogen receptor assays vary when investigated in combination with progesterone receptor.

Dielectric spectroscopy of breast tissue — Measurement and permittivity models

The knowledge of dielectric properties of breast tissue in a wide frequency range of 0.1 to 20 GHz forms the foundation for a variety of novel microwave techniques for breast cancer detection [1,2,3]. In collaboration, the Universities of Calgary and Wisconsin-Madison are building an extensive database of breast tissue dielectric properties for further advances of microwave technologies for breast cancer detection and treatment [1,5,7].