Miriam Rosin

High throughput image cytometry for detection of suspicious lesions in the oral cavity

The successful management of oral cancer depends upon early detection, which relies heavily on the clinicians ability to discriminate sometimes subtle alterations of the infrequent premalignant lesions from the more common reactive and inflammatory conditions in the oral mucosa. Even among experienced oral specialists this can be challenging, particularly when using new wide field-of-view direct fluorescence visualization devices clinically introduced for the recognition of at-risk tissue. The objective of this study is to examine if quantitative cytometric analysis of oral brushing samples could facilitate the assessment of the risk of visually ambiguous lesions. About 369 cytological samples were collected and analyzed: (1) 148 samples from pathology-proven sites of SCC, carcinoma in situ or severe dysplasia; (2) 77 samples from sites with inflammation, infection, or trauma, and (3) 144 samples from normal sites. These were randomly separated into training and test sets. The best algorithm correctly recognized 92.5% of the normal samples, 89.4% of the abnormal samples, 86.2% of the confounders in the training set as well as 100% of the normal samples, and 94.4% of the abnormal samples in the test set. These data suggest that quantitative cytology could reduce by more than 85% the number of visually suspect lesions requiring further assessment by biopsy.

Gender- and ethnicity-specific survival trends of oral cavity and oropharyngeal cancers in British Columbia

IntroductionA shift in etiology of oral cancers has been associated with a rise in incidence for oropharyngeal cancers (OPC) and decrease for oral cavity cancers (OCC); however, there is limited information about population-based survival trends. We report epidemiological transitions in survival for both OPC and OCC from a population-based cancer registry, focusing upon gender and ethnic differences.MethodsAll primary oral cancers diagnosed between 1980 and 2005 were identified from the British Columbia Cancer Registry and regrouped into OPC and OCC by topographical subsites, time periods (1980–1993 and 1994–2005), stage at diagnosis, and ethnicity. Cases were then followed up to December 2009. Using gender-based analysis, actuarial life tables were used to calculate survival rates, which were compared using Kaplan–Meier curves and log-rank tests.ResultsFor OPC, survival improved, significant for tonsil and base of tongue in men and marginally significant at base of tongue in women. This improvement occurred in spite of an increase in late-stage diagnosis for OPC in both genders. Interestingly, there was no difference in survival for early- and late-stage disease for OPC in men. For OCC, there was a decrease in survival for floor of mouth cancers in both genders although significant in women only. South Asians had the poorest survival for OCC in both genders.ConclusionSurvival for OPC improved, more dramatically in men than women, in spite of late-stage diagnosis and increasing nodal involvement. Given the poor survival rates and need for early detection, targeted OCC screening programs are required for South Asians.

Abstract A13: Quantitative pathology toolbox: Improvement in prediction of progression risk for oral premalignant lesions using both interactive and automated image analysis

For the promise of Quantitative Pathology (QP) to be clinically accepted it must provide new information that is clinically usable (and hence actionable). This must be accomplished in a fashion that is not onerous (expensive/time-consuming/require specialized training) to the pathologist relative to the value of the information provided. As an example a major barrier to oral cancer prevention is the inability to predict progression risk for oral premalignant lesions by conventional pathology alone that can be addressed by QP. We present two approaches for the quantitative analysis of FFPE sectioned oral tissue. In one approach the user selects the area of epithelium to be analyzed and visually filters the cells to be analyzed, the other is an automated approach in which the user only circles the epithelium to be analyzed. In both approaches the cell nuclei are automatically segmented, 110 features per nuclei calculated and used to determine how normal or cancer like the nucleus is (and in the fully automated approach if the objects are single intact nucleus or not), then the distribution of nuclei values within the area of interest is used to generate a Quantitative Pathology Scores (QPS) for the tissue. These tissue measures were used alone or in combination with other markers to perform risk assessment in patients from a very large oral cancer prediction longitudinal study. Also the scores can be combined with other risk markers such as Loss of Heterozygosity (LOH) analysis to improve risk stratification. A combination of LOH based predictors and QPS thresholds were trained to refine three previously validated LOH defined- risk groups. The combined model defined a low, a medium and a high risk of progression to cancer categories. For the 104 low risk cases so classified, 98.1% do not progress to cancer (used to define a relative risk [RR] of 1). In contrast, 15% of the 106 classified medium risk cases (RR= 7.85) and 65% of the 26 high-risk cases (RR = 34) progress. This is a substantial improvement over just the LOH based classification and significantly better than dysplasia grade for risk prediction. In a validation set of 43 mild to moderate dysplasia cases with long term follow-up, 100% of the 23 cases classified as low risk by the combined algorithm did not progress, 43% of the 7 cases classified as medium risk by the combined algorithm progressed and 92.3% (12 out 13) of the cases classified as high risk by the combined algorithm progressed. These validation results strongly support the combination of these approaches for facilitating risk prediction and improving patient management. This combined risk model is also a suitable intermediate endpoint biomarker of transformation risk for oral tissue and is being used in multicenter (8) Canadian Optically guides Oral Cancer Surgical Trial as part of the quantitative evaluation of surgical margin tissue. This work was funded by the NIDCR, NIH and by the TFRI. Note: This abstract was withdrawn after the Proceedings were printed and, therefore, was not presented at the conference. Citation Format: Calum MacAulay, Miriam Rosin, Lewei Zhang, Catherine Poh, Michele Williams, Martial Guillaud. Quantitative pathology toolbox: Improvement in prediction of progression risk for oral premalignant lesions using both interactive and automated image analysis. [abstract]. In: Proceedings of the Thirteenth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2014 Sep 27-Oct 1; New Orleans, LA. Philadelphia (PA): AACR; Can Prev Res 2015;8(10 Suppl): Abstract nr A13.

Predicting Progression of Oral Dysplasia—Response

We thank Drs. Gomes, Fonseca-Silva, and Gomez for their comments on our recently published article ([1][1]). That article validated a LOH risk model for use in differentiating between high-risk and low-risk oral dysplasias—a critical barrier in selecting patients for advanced oral cancer

Abstract 4677: The differences among various age groups of oral cancers in British Columbia

Oral squamous cell carcinoma (OSCC) is a disease commonly in those who are older and/or heavily smoke. However, the incidence of younger group is increasing world-wide. Research to understand this shift can have significant impact on oral cancer control. Objectives: 1) To determine the characteristics of OSCC in different age groups in a longitudinal study and 2) To compare the differences among groups. Methods: From 1990 to 2008, we recruited 536 OSCCs for the BC Oral Cancer Prediction and Longitudinal (OCPL) Study. We have arbitrarily put them into groups based on the age at initial OSCC diagnosis: 43 (8%) were equal to or under age 40 years (Young group); 212 (40%) were diagnosed between age 50 to 65 (Conventional group); 91 (17%) were age 75 or older (Old group). To better define the difference among various age groups, we excluded those between ages 41-49 (12%) and 66-74 (24%). Demographics, smoking habit, clinicopathological features of the lesion, treatment modalities, and outcome data were collected. The data were also compared with those from the BC Cancer Registry in the same period years to determine the representativeness of the BC population. Results: The Young OSCC from the OCPL Study had no significant differences from those in Registry in gender, anatomical location, tumor staging, and differentiation. When compared to the Conventional group, the Young group showed less Caucasian (66% vs. 86%, P = 0.005), less smokers (35% vs. 77%, P Conclusion: Various age groups of early-staged oral cancer show different clinical behaviors. Nonsmokers and tongue-located tumor characterize the Young group which has a better prognosis in survival. More molecular studies are needed for better understanding the underlying driven force. An attempt to characterize the difference using-molecular tools is ongoing. This might shed the light in difference among different age groups. (Supported by grant R01 DE17013 from the National Institute of Dental and Craniofacial Research and grant CCSRI-20336 from Canadian Cancer Society Research Institute) Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4677. doi:10.1158/1538-7445.AM2011-4677

Abstract 3677: Prediction of oral cancer recurrence at post-surgery follow-up using fluorescence visualization

Background: Recurrence is observed in up to 30% of surgically treated high-risk oral lesions (HRLs, severe dysplasia, carcinoma in situ and cancer) and is associated with poor prognosis. Reactive tissue change observed post-treatment often masks recurrence and makes early detection difficult. New advances using fluorescence visualization (FV) represent a promising approach to this problem that may facilitate early detection of disease recurrence. Objectives: 1) To identify FV alterations post-treatment of HRLs and 2) To determine whether a relationship exists between FV alterations and local recurrence. Methods: In the BC Oral Cancer Longitudinal Study, we have recruited ∼400 HRLs with surgical treatment as the primary modality. Patients eligible for this analysis included those that had an initial follow-up appointment within 6 months of surgery with at least 2 follow-up appointments within the first year of treatment, with each visit involving FV examination of the treatment site. Recurrence was defined as the presence of biopsy-proven HRLs. The ‘plateau’ of the FV during the follow-ups is defined as the change of FV measurement in width within ± 1 mm (superior-inferiorly) in various time intervals of 3, 6, 9, or 12 months. Results: A total of 198 patients were identified of which 24 (12%) had lesion recurrence at the previously treated site. There was no difference in gender, age, ethnicity, smoking habit, anatomical site, primary diagnoses, and follow-up time between the recurrence and non-recurrence groups. The duration of plateau was longer in non-recurrence group compared to those in recurrence group (P = 0.03). When we examined the duration ‘plateau’ at various intervals of follow-ups, among 166 patients/lesions with at least 9 months follow-ups, we found out that the presence of plateau was more frequent in the non-recurrence group than those recurrent case (P = 0.03). Using linear mixed effects and logistic regression analyses, there was a significant difference of the individual slopes between recurrence and non-recurrence group (P = 0.001), adjusted for the individual intercepts (i.e., the original FV width). Conclusion: The stability, i.e., timing and duration of the plateau, of the FV alteration during post-surgical follow-ups can be potentially used to predict local recurrence of HRLs. (Supported by Supported by grant R01 DE17013 from the National Institute of Dental and Craniofacial Research and grant CCSRI-20336 from Canadian Cancer Society Research Institute; Canadian Institute for Health Research and Michael Smith Foundation from Health Research) Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3677. doi:10.1158/1538-7445.AM2011-3677

Abstract A9: Phenotype matters in the prediction of cancer risk of oral premalignant lesions (OPL)

Histology remains the most reliable way for predicting cancer risk of premalignant (preinvasive) lesions if the OPLs show high-grade changes (i.e. severe dysplasia or carcinoma in situ, CIS): however, it is a poor predictor of the cancer risk of OPLs with no or low-grade (mild/moderate) dysplasia (termed LGOPL). It is possible that there are subtle histological differences between progressing LGOPLs and nonprogressing LGOPLs. In a recent retrospective study (Cancer Research 2008, 68:3099–107), we have shown that nuclear phenotypic score (NPS) as measured by a computer-driven microscope imaging system could serve as an adjunct tool to assist pathologists in judging the progression risk of LGOPLs Objective: to assess the potential of this new tool in identifying high-risk LGOPLs from an ongoing prospective study and to give an interim report of our results. Methods: 284 primary LGOPLs from 284 patients were studied: 47 hyperplasias, 116 mild and 121 moderate dysplasias. Thoinin-Feulgen stained sections were imaged and analyzed to generate a NPS for each sample. The NPS was correlated with histopathology, clinical variables and outcome (progression to severe dysplasia, CIS or invasive cancer). Results: Elevated NPS was significantly associated with progression: high NPS (≥ 4.5) was associated with a 4.7-fold increase in risk of progression as compared to low NPS ( Conclusions: These data support the potential utility of automated quantitative microscopy technology to assist the pathologist in assessing progressing potential of low-grade OPLs (Supported by grant R01DE13124, NIDCR). Citation Information: Cancer Prev Res 2011;4(10 Suppl):A9.

Abstract PL05-04: From basic science to public health: The Canadian approach to oral leukoplakia

Oral cancer is a major health problem worldwide (over 300,000 new cases identified each year) with numbers projected to climb steadily. Although the site is easily accessed, it is most often detected at late-stage, leading to high mortality and morbidity rates that have shown little change for decades. Much of the projected increase in this disease will occur in low- and middle-income countries with very limited resources. Oral cancer is a good target for employing systems models for prevention and intervention. It shares etiology with many cancers (tobacco usage, alcohol consumption, diet, and infection) so prevention approaches have a universal application. Common challenges exist in both developing and wealthier countries: low awareness of health care professionals, low public awareness, low priority within public health, inequities in care, infrastructure and human resources deficits, system fragmentation and lack of coordinated advocacy and leadership. Approaches tend to be treatment rather than prevention focused. There is a need for development of new strategies for management of the disease. The objective of this presentation is to describe a population health-focused approach taken in British Columbia to improve oral cancer control that has drawn together provincial resources, integrating them into a comprehensive system of structures and players. The effort spans the continuum of care (prevention, early detection, diagnosis and treatment of the disease) working through multiple approaches, at multiple levels and across multiple sectors. Its growth is guided through partnerships and networks with health professionals and societies, by social marketing and epidemiological surveillance, and by technology development for early detection, risk assessment and cancer treatment within an ongoing NIH-funded longitudinal study. The approach has grown around an opportunistic screening network of dentist and ENT surgeons that has existed in British Columbia for ∼27 years. This network is linked through a centralized oral biopsy service to referral resources to facilitate patient management. We have engaged and empowered this network through a combination of approaches (focus groups of community dental health professionals, continuing education forums, news releases, journal publications, and social marketing strategies) with an aim to increase awareness of the importance of screening activity and to build social norms among dental professionals to enhance their ownership of this domain. In collaboration with the College of Dental Surgeons of British Columbia, a Guideline was released in 2008 to move activities from an ad hoc to a standardized, quality controlled approach, with formal integration of screening into the regular oral exam for each patient. This has resulted in increased screening among dental professionals who have seen the guideline, among whom 84% screen as part of routine exams, compared to 65% of those not aware of the guideline. A second offshoot of activity within the program is the development within the Oral Biopsy Service of an Oral Leukoplakia and Dysplasia Registry that will link to the British Columbia Cancer Registry to track the impact of changes in practice on outcomes. This project is supported by the Canadian Partnership Against Cancer (CPAC) with input from other provincial oral biopsy services across Canada. This will allow for development of parallel dental network and registry structures to better define the natural history of the disease and improve its management at a national level. We expect to reach 2/3 of the BC population through a strengthened dental office network and referral pathway. However, access to this network remains a challenge for the remaining population. Tailored strategies are being developed in partnership with the South Asian community, the Vancouver First Nations community, the Downtown Eastside in Vancouver, and rural BC. Since developing countries share many of the same barriers to health care utilization with these underserved communities, we have opened dialogues with international partners to gain input and provide knowledge exchange around facilitators and barriers to screening activities in low-resource settings. This increased screening activity has been coupled to the development of a streamlined referral pathway for risk assessment in dysplasia clinics for standardized risk assessment and follow-up of high-risk patients (an NIH-NIDC-funded initiative). These clinics use technology developed within an ongoing longitudinal study to identify and assess high-risk lesions: optical devices to improve clinical visualization; high-throughput computer microscopy systems to predict future behavior of early lesions in a cost-effective fashion, using subtle histological and cytological indicators; and molecular markers of risk. The impact of this technology on driving change in clinical practice is already apparent. Optical fluorescence technology has been used to detect occult disease in patients going to surgery. Its use to guide surgical margin delineation has resulted in a marked reduction in recurrence rates ∼10 fold or more (from ∼25% recurrence to close to zero) that is now being explored in multicenter randomized control trial for device efficacy supported by the Terry Fox Research Institute. This initiative promises to facilitate the better management of early disease detected within the system, and provides a structure for rigorous assessment of these innovations as well as a foundation for knowledge translation and scale-up. Conclusion: We are engaged in trials of innovative technology, social mobilization, and knowledge translation to support system-wide change for equitable population-based control of oral cancer in British Columbia. This effort is a model that demonstrates how resources can be pulled together and optimized to provide a centralized structure for shaping new approaches to detection, management, and prevention of disease. Citation Information: Cancer Prev Res 2010;3(12 Suppl):PL05-04.