Christopher G. Ball
University of Ottawa
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Pathology International | 2014
Kien T. Mai; Shaheed W. Hakim; Christopher G. Ball; Trevor A. Flood; Eric C. Belanger
Nested/microcystic (NV/MV) urothelial carcinoma (UC) variants are associated with mild cytologic atypia and commonly present at high‐stage disease. The histopathogenesis is investigated using urothelial basal cell markers. Archival 14 NV/MV and three inverted papilloma (IP) were immunostained for CD44, cytokeratin 5 (CK5), CK34bE12 and p63. Twenty consecutive cases of invasive high‐grade UC including 14 superficial and 6 muscle‐invasive UC cases were used as control. Immunostaining was scored as high for staining of full or more than 50% thickness of the epithelial nest or epithelium and low for lesser immunoreactivity and negative reactivity. All 14 NV/MV, 3 IP and 6 control cases showed a high score of immunoreactivity for CK5, CD44, CK34bE12 and focally for p63. The remaining control cases showed a high score of immunoreactivity for CK34bE12, while negative or low for CK5, CD44 and p63. In conclusion, immunoreactivity CK5 and CD44 commonly immunostained NV/MV and some invasive high grade UC. Other basal cell markers (CK34bE12 and p63) appear to be non specific or non sensitive. NV and MV and some UC likely represent a subset of UC displaying immunohistochemical features of urothelial basal cells. They had tendency of endophytic growth and early invasion despite the innocuous cytologic appearance.
Pathology Research and Practice | 2015
Kien T. Mai; Luan D. Truong; Christopher G. Ball; Phillip Williams; Trevor A. Flood; Eric C. Belanger
We characterize invasive urothelial carcinoma (UC) exhibiting urothelial basal cell immunohistochemical markers. Consecutive invasive UCs were immunostained with CK20 and urothelial basal cell markers, cytokeratin 5 (CK5)/CD44. Immunostaining for CK5 and CD44 was scored as follows: positive for staining of more than 25% thickness of the epithelial nest or epithelium and low for lesser immunoreactivity. Invasive urothelial carcinoma (UC) exhibiting positive CK5/CD44 staining was designated as basal-like UC (BUC). In this study, of 251 invasive UC (pT1 in 57% and pT2-4 in 43%), BUC accounted for 40% of cases (accounting for most pT2-4 UC) and often presented as non-papillary UC without previous history of UC. In addition, BUC exhibited uniform nuclei with lesser degree of atypia than non BUC and decreased or negative cytokeratin 20 reactivity. Nested and microcystic variants of UC immunohistochemically stained as BUCs. Invasive non-BUCs were often papillary with marked cytologic atypia and pleomorphism, and accounted for most pT1 UC. The rates of perivesical invasion, lymph node and distant metastases were higher for BUC than non-BUC. All nine cases with absent/minimal residual in situ UC in 102 radical cystectomy specimens were from invasive non-BUC. BUC is distinguished from non-BUC due to this aggressive behavior, distinct immunohistochemical profile, and predominant non-papillary architecture. Our findings are consistent with recent studies identifying a subtype of muscle-invasive UC with molecular expression of basal cell and luminal cell molecular profiles. Our study further supports categorizing invasive UCs into these subtypes with different biological behaviors, possibly contributing to better therapeutic strategies.
Diagnostic Cytopathology | 2014
Kien T. Mai; Christopher G. Ball; Zuzana Kos; Eric C. Belanger; Shahidul Islam; Harman S. Sekhon
Cystoscopic urine obtained before the resection of low‐grade urothelial carcinoma (LGUC), with adequate cytological sampling of the tumor, frequently revealed the presence of three‐dimensional cell groups with disordered nuclei and cellular discohesion (3DDD). 936 cystoscopic urine specimens were categorized into five groups: Group 1 (80 specimens) with biopsy‐proven LGUC within 6 months of cytologic examination, Group 2 (23 specimens) with biopsy proven LGUC within 6 to 36 months of cytologic examination, Group 3 (527 specimens) with a history of LGUC but no tumor for a period of greater than 3 years, Group 4 (300 specimens) with no association with LGUC, and Group 5 (6 specimens) with urinary lithiasis. Specimens with scant cellularity accounted for 20% of those in Group 1. For 3DDD in detecting LGUC in adequate cystoscopic urine, the sensitivity was 70%, specificity was 94%. Two‐ or three‐dimensional cell groups with ordered nuclei and/or cellular non‐discohesion were often seen in specimens from Groups 4 or 5. The 3DDD was present in a significant number of cases with concurrent negative cystoscopic findings but also positive LGUC in ensuing follow‐up. In these cases, 3DDD with or without tumor identified at concurrent cystoscopy were found to be morphologically similar. Furthermore, the presence of 3DDD in 8% of Group 3 likely represents urothelial dysplasia that is not cystoscopically detectable. The high specificity and sensitivity of 3DDD is demonstrated. These findings are consistent with the decreased cell adhesion and disordered nuclear arrangement of low grade urothelial neoplasia. Diagn. Cytopathol. 2014;42:555–563.
Applied Immunohistochemistry & Molecular Morphology | 2016
Kien T. Mai; Christopher G. Ball; Eric C. Belanger
Background:We investigated the clinical and pathologic significance of a subgroup of noninvasive papillary urothelial carcinomas (UCs) expressing reactivity to urothelial basal cell markers. Design:In total, 302 consecutive cases of noninvasive papillary UC were evaluated immunohistochemically with cytokeratin 5 (CK5)/CD44. Any UC that was reactive for greater than 25% thickness of the urothelium was designated as basal-like urothelial carcinoma (BUC); remaining UC cases were designated as non-BUC. The follow-up period was up to 3 years. Historical review of UC was extended for up to 3 retrospective years. Results:Among 302 noninvasive UC, BUC was identified in 33 of 256 (12.9%) low-grade UC and 8 of 46 (17%) high-grade UC (P=0.041). Immunoreactivity for CD44 was similar to that of CK5, but displayed weaker and more diffuse staining. CK20 was reactive in 9 cases, primarily high-grade BUC. Other basal cell markers (34bE12, p63, bcl2, and EP4) were found to be neither sensitive nor specific in detecting UC with high CK5 expression. In comparison with non-BUC, BUC was associated with increased multifocality, larger tumor size, higher recurrence rate, and more frequent upgrading and stage progression. In the follow-up period of 3 years, distant metastasis occurred in 6 cases of which 5 were in the BUC subgroup. Conclusions:Our results showed that noninvasive papillary BUC represents a small subset associated with increased risk of tumor recurrence and progression. The aggressive behavior is likely associated with basal-like features of BUC, as seen in carcinomas with basal cell features in other body sites.
Cardiovascular Ultrasound | 2015
Frank Secretain; Andrew Pollard; Mesbah Uddin; Christopher G. Ball; Andrew J. Hamilton; Robert Tanzola; Joelle Thorpe; Brian Milne
BackgroundRisks associated with air emboli introduced during cardiac surgery have been highlighted by reports of postoperative neuropsychological dysfunction, myocardial dysfunction, and mortality. Presently, there are no standard effective methods for quantifying potential emboli in the bloodstream during cardiac surgery. Our objective was to develop software that can automatically detect and quantify air bubbles within the ascending aorta and/or cardiac chambers during cardiac surgery in real time.FindingsWe created a software algorithm (“Detection of Emboli using Transesophageal Echocardiography for Counting, Total volume, and Size estimation”, or DETECTS™) to identify and measure potential emboli present during cardiac surgery using two-dimensional ultrasound. An in vitro experiment was used to validate the accuracy of DETECTS™ at identifying and measuring air emboli. An experimental rig was built to correlate the ultrasound images to high definition camera images of air bubbles created in water by an automatic bubbler system. There was a correlation between true bubble size and the size reported by DETECTS™ in our in vitro experiment (r = 0.76). We also tested DETECTS™ using TEE images obtained during cardiac surgery, and provide visualization of the software interface.ConclusionsWhile monitoring the heart during cardiac surgery using existing ultrasound technology and DETECTS™, the operative team can obtain real-time data on the number and volume of potential air emboli. This system will potentially allow de-airing techniques to be evaluated and improved upon. This could lead to reduced air in the cardiac chambers after cardiopulmonary bypass, possibly reducing the risk of neurological dysfunction following cardiac surgery.
Academic forensic pathology | 2018
Christopher G. Ball; Jayantha C. Herath
Interpretation of deaths in hostile environments may be informed by postmortem microscopic examination of injured tissues. In context with their macroscopic correlates, the commonly observed histologic changes seen in environmental deaths are reviewed—these include exposure (i.e., hypothermia and hyperthermia), fire, electrocution, and water. Rarely observed pathognomonic findings are highlighted. While it may not yield specific findings, microscopic examination is one of the necessary steps of a thorough postmortem examination.
Pathology International | 2015
Kien T. Mai; Luan D. Truong; Christopher G. Ball; Bernhard Olberg; Chi K. Lai; Bibianna Purgina
We hypothesize that cystic structures in metastatic papillary thyroid carcinoma (PTC) develop along the framework of lymphatic channels. To investigate this phenomenon, different categories of PTC were immunostained for D2‐40 and TTF1. In this study, reactivity for D2‐40 was considered as positive when there is membranous staining as often seen in lymphatic endothelial cells. Thirty cases of PTC with lymph node metastasis or with potential for lymphatic invasion and 20 cases metastatic PTC in lymph nodes were reviewed and found to show double/mosaic immunoreactivity for TTF1/D2‐40 in 40–100% of cases. PTC metastasis in lymph nodes with cysts and some branching lymphatic‐like channels lined by follicular cells with or without nuclear features of PTC were diffusely reactive to TTF1, and focally to D2‐40. For primary and metastatic PTC, focal membranous D2‐40 reactivity was also demonstrated in cysts or cleft linings. For25 thyroid neoplasms with no known potential for lymphatic invasion, there was no such immunoreactivity. The mosaic or double immunoreactivity for TTF1/D2‐40 suggests lymphatic cancerization and possible endothelial mimicry of follicular cells. Mosaic/double immunoreactivity is helpful to detect the hidden pattern of lymphatic invasion masquerading as ‘benign‐appearing’ follicles and supports our hypothesis of malignant cells developing along the lymphatic framework.
Academic forensic pathology | 2015
Christopher G. Ball; John P. Veinot
Historical development of percutaneous coronary intervention (PCI) from percutaneous coronary transluminal angioplasty (PCTA) is outlined, along with the progression in the development of coronary artery stents—from the earliest bare-metal stents to drug-eluting stents to the current leading edge of bioresorbable and polymer-free stents. The early, medium, and late complications of PCTA and PCI are explained briefly, and with respect to stent development. Finally, common techniques to remove section stented vessels are outlined.
Journal of obstetrics and gynaecology Canada | 2014
Lana Saciragic; Christopher G. Ball; Shahidul Islam; Michael Fung-Kee-Fung
BACKGROUND All cases reported to date of endometrioid endometrial adenocarcinoma (EEA) associated with pregnancy have been treated surgically or medically. We describe a case of EEA in pregnancy that was managed expectantly, allowing for observation of the natural course of the disease. CASE A 36-year-old woman, gravida 2 para 1, presented at eight weeks of pregnancy with heavy vaginal bleeding. Ultrasound assessment confirmed a missed abortion, and the patient underwent dilatation and curettage. Tissue pathology primarily suggested grade 1 EEA. The patient chose expectant management. Eight months later, she returned with vaginal bleeding. Hysterectomy was performed and the hysterectomy specimen showed FIGO grade 1 stage 1A EEA. CONCLUSION Treating EEA associated with pregnancy is challenging. Our experience in the case described here suggests that expectant management should not be undertaken due to a high risk of recurrence.
Archive | 2007
Christopher G. Ball; Andrew E. Pollard