Wolfson Institute of Preventive Medicine - Barts and The London

GLACIER and ICICLE – studies investigating the genetics of breast carcinomas in situ of the lobular type (GLACIER) and the ductal type (ICICLE)

King's College London

Project Investigator:  Professor Elinor Sawyer

Trial Information


The GLACIER (A study to investigate the Genetics of LobulAr Carcinoma In situ in EuRope) Study looked at people who had a diagnosis of lobular carcinoma in situ (LCIS) or a type of breast cancer called invasive lobular cancer in order to identify new genes which may have caused this condition to occur, as well as identifying cases of LCIS which may progress to invasive cancer.

Lobular carcinoma in situ (LCIS) is a clinically undetectable form of non-invasive breast cancer, and is typically an incidental finding when a biopsy is performed for another reason. The advent of screening mammography and the increasing breast biopsy rate has meant that a diagnosis of LCIS is becoming more common. Although a diagnosis of LCIS is often an incidental finding, it is significant as it is a risk factor for the development of subsequent invasive breast cancer in either breast, with the majority of these subsequent invasive cancers being invasive lobular carcinomas. Unfortunately the optimum management for LCIS is not known, as we cannot predict those patients who are likely to progress to invasive breast cancer.

The GLACIER study recruited over 2000 women with LCIS or invasive lobular carcinoma over 5 years, and closed to recruitment in 2012. Controls without breast cancer were also recruited to the study.



The ICICLE (A study to Investigate the genetiCs of In situ Carcinoma of the ductaL subtypE) Study identified patients with a past history or recent diagnosis of ductal carcinoma in situ (DCIS) from participating centres in the UK in collaboration with the National Cancer Research Network with the aims to identify genes which predispose to DCIS, and also to identify those cases which are more likely to subsequently develop invasive cancer.

DCIS is a form of non-invasive breast cancer. Previously it typically presented as a palpable mass. Now with the advent of screening mammography, the majority of cases are diagnosed whilst still clinically occult. Women with a family history of breast cancer are at increased risk of developing breast carcinoma in situ. The aim of this study was to collect a large resource of cases to identify inherited variation that predisposes women to develop DCIS, as current treatment is aimed at preventing disease recurrence but critically it is not possible to predict which women would progress.

The ICICLE Study recruited over 5000 women over 5 years, and closed to recruitment in 2013. Controls without breast cancer also took part in the study.


Data Processing & Patient Confidentiality

Follow-up Study

Did you take part in the ICICLE or GLACIER study sponsored by QMUL and led by Rebecca Roylance and Elinor Sawyer?

We are gathering information on those took part and consented for their data/sample use in future studies to see if anyone has recurred or progressed since the close of these studies.

King’s College London are now looking after the initial studies and the follow-up study, so if you have any questions please contact Professor Elinor Sawyer (elinor.sawyer@kcl.ac.uk) or Jasmine Timbres (jasmine.timbres@kcl.ac.uk) from the King’s College London Breast Cancer Genetics Team.

Further Information


The sponsorship for the GLACIER and ICICLE studies changed in 2019 from Queen Mary’s University London to King’s College London, although still under the supervision of Co-Chief Investigator Professor Elinor Sawyer. For more information, contact Professor Elinor Sawyer (elinor.sawyer@kcl.ac.uk) or Jasmine Timbres (jasmine.timbres@kcl.ac.uk).



  • Sawyer, E., Petridis, C., Kohut, K., Gorman, P., Caneppele, M. and Roylance, R. (2012). 121 Risk Factors Associated with Lobular Carcinoma in Situ: Results of the GLACIER Study. European Journal of Cancer, 48, pp.S75-S76. 48. S75-S76. 10.1016/S0959-8049(12)70189-2. https://www.ejcancer.com/article/S0959-8049(12)70189-2/fulltext


  • Sawyer, E., Roylance, R., Petridis, C., Brook, M., Nowinski, S., Papouli, E., Fletcher, O., Pinder, S., Hanby, A., Kohut, K., Gorman, P., Caneppele, M., Peto, J., dos Santos Silva, I., Johnson, N., Swann, R., Dwek, M., Perkins, K., Gillett, C. et al. (2014). Genetic Predisposition to In Situ and Invasive Lobular Carcinoma of the Breast. PLoS Genetics, 10(4), p.e1004285. 10.1371/journal.pgen.1004285. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3990493/



  • Shah, V., Nowinski, S., Levi, D., Shinomiya, I., Kebaier Ep Chaabouni, N., Gillett, C., Grigoriadis, A., Graham, T., Roylance, R., Simpson, M., Pinder, S. and Sawyer, E. (2017). PIK3CA mutations are common in lobular carcinoma in situ, but are not a biomarker of progression. Breast Cancer Research, 19(1).19. 10.1186/s13058-016-0789-y. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5240238/


  • Petridis, C., Brook, M., Shah, V., Kohut, K., Gorman, P., Caneppele, M., Levi, D., Papouli, E., Orr, N., Cox, A., Cross, S., dos-Santos-Silva, I., Peto, J., Swerdlow, A., Schoemaker, M., Bolla, M., Wang, Q., Dennis, J., Michailidou, K., Roylance, R., Sawyer, E. et al. (2016). Genetic predisposition to ductal carcinoma in situ of the breast. Breast Cancer Research, 18(1). 10.1186/s13058-016-0675-7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4756509/


  • Petridis, C., Arora, I., Shah, V., Megalios, A., Moss, C., Mera, A., Clifford, A., Gillett, C., Pinder, S., Tomlinson, I., Roylance, R., Simpson, M. and Sawyer, E. (2019). Frequency of pathogenic germline variants in BRCA1, BRCA2, PALB2, CHEK2 and TP53 in ductal carcinoma in situ diagnosed in women under the age of 50 years. Breast Cancer Research, 21(1). 21. 10.1186/s13058-019-1143-y. https://www.ncbi.nlm.nih.gov/pubmed/31060593