Christina Clarke

Administrative Appointments

• Consulting Assistant Professor, Dept. of Health Research and Policy, Stanford (2005 - present)
• Steering Committee, California Teachers Study (2006 - present)
• Scientific Communications Advisor, Cancer Prevention Institute of California (2011 - present)

Professional Education

Current Research Interests

Breast cancer: This research area involves descriptive work to describe geographic and temporal variations in incidence especially in the Bay Area, and analytic efforts to uncover possible immunologic and infectious causes. Dr. Clarke was among the first to note and report on the unprecedented decline in breast cancer incidence that occurred in mid-2002. Dr. Clarke recently completed two population-based case-control studies to explore environmental factors associated with immune system development (as identified by the “hygiene hypothesis” literature for asthma and allergy development). With colleagues, she is also investigating associations of breast cancer with immune genes, human herpesviruses, and other markers of immune function and infection.

Lymphoid malignancies: this research area emphasizes population-based study of the causes and outcomes of Hodgkin lymphoma (HL) and the many subtypes of non-Hodgkin lymphoma (NHL). Her dissertation research described patient survival after HL in the general population and with respect to a certain molecular marker (Epstein-Barr virus in HL tumor cells). With Dr. Sally Glaser, she has examined reproductive, infectious, social class and other risk factors for Hodgkin lymphoma in a population-based case control study of women. In addition to descriptive efforts to describe NHL incidence, she has conducted methodologic studies to improve the surveillance and study of NHL subtypes, which has been challenged by changing classifications over time and by inability to separate HIV-related from –unrelated forms. She is a co-leader of the Pathology Working Group of the NCI-backed International Interlymph Consortium.

Cancer surveillance: As co-Investigator for the Greater Bay Area Cancer Registry, part of the NCI SEER and California Cancer Registry programs, Dr. Clarke monitors changes in cancer incidence and survival patterns among various population subgroups, particularly those defined by geography, race/ethnicity and socioeconomic status. In particular, she has examined cancer incidence survival patterns jointly by racial/ethnic and socioeconomic characteristics. Recent work with Dr. Susan Swetter at Stanford also emphasizes melanoma incidence, especially how possible underreporting by physicians may have led to underestimates of the burgeoning melanoma epidemic. She is also working on methodologies for cancer surveillance research, an emerging subdiscipline of epidemiology concerned with the analysis of cancer registry and other routinely collected health data. An ARRA funded proposal with Dr. Matt Kreuter at Washington University focuses on better means of visually displaying cancer registry data.

Patientcentric epidemiology: traditional methods for recruitment and data collection as part of population-based research emphasize the preferences and convenience of researchers, when it should be the other way around. With multidisciplinary colleagues in marketing, information technology, communications, and graphic design, we are working on new methodologies for recruitment, data collection, and other aspects of the research "user experience".

Publications

• Body size and the risk of postmenopausal breast cancer subtypes in the California Teachers Study cohort. Canchola AJ, Anton-Culver H, Bernstein L, Clarke CA, Henderson K, Ma H, Ursin G, Horn-Ross PL. Cancer Causes Control. 2012
• Gastric cancer incidence among Hispanics in California: patterns by time, nativity, and neighborhood characteristics. Chang ET, Gomez SL, Fish K, Schupp CW, Parsonnet J, Derouen MC, Keegan TH, Clarke CA, Glaser S. Cancer Epidemiol Biomarkers Prev. 2012
• Nativity and papillary thyroid cancer incidence rates among Hispanic women in California. Horn-Ross PL, Chang ET, Clarke CA, Keegan TH, Rull RP, Quach T, Gomez SL. Cancer. 2012; 118 (1): 216-22
• Occurrence of breast cancer subtypes in adolescent and young adult women. Keegan TH, Derouen MC, Press DJ, Kurian AW, Clarke CA. Breast Cancer Res. 2012; 14 (2): R55
• Adulthood residential ultraviolet radiation, sun sensitivity, dietary vitamin D, and risk of lymphoid malignancies in the California Teachers Study. Chang ET, Canchola AJ, Cockburn M, Lu Y, Wang SS, Bernstein L, Clarke CA, Horn-Ross PL. Blood. 2011; 118 (6): 1591-9