Concept: Overview of the Manitoba Cancer Registry and Treatment Data

Introduction

This concept provides an overview of the Manitoba Cancer Registry and Treatment data held in the Manitoba Population Research Data Repository (Repository). Most of the content in this concept is based on information from the MCHP deliverable Cancer Data Linkage in Manitoba: Expanding the Infrastructure for Research by Lix et al. (2016). Most recently, an update to the cancer stage information was added.

The purpose of this concept is to provide researchers and analysts with information about the Manitoba Cancer Registry and Treatment data, including a general overview of the structure and content of the Cancer Registry and Cancer Treatment datasets, and more detailed information on specific aspects of the data. The concept also provides a summary of the data quality assessment of the Manitoba Cancer Registry undertaken by Lix et al. (2016).

The Manitoba Cancer Registry Database

The Manitoba Cancer Registry, created by and maintained at CancerCare Manitoba (CCMB), captures all cases of cancer in the province identified at the time of biopsy, surgery, or hospital discharge; death certificates and autopsy records are also used to ascertain cancer cases. Registrars compile information about the characteristics of the patient, tumour, and treatment for inclusion in the registry.

In the MCHP Data Repository, the Manitoba Cancer Registry and Treatment data is comprised of two separate datasets:


1. Cancer Registry dataset - contains all the incident cases of cancer diagnosed in the province from January 1, 1984 forward;
   
2. Cancer Treatment dataset - contains summary-level treatment information for patients entered in the Cancer Registry dataset.

For more information, including links to the Manitoba Cancer Registry and Treatment data description and technical information in the Metadata Repository (internal access only), see the Manitoba Cancer Registry and Treatment Data glossary term.

1. The Cancer Registry Dataset

The Cancer Registry dataset contains records for each new case of cancer, and includes patient demographics (birth date, sex, postal code, age at diagnosis), cancer site, cancer stage (available from January 1, 2004 forward), method of diagnosis, date and place (facility) of diagnosis, and other tumour characteristics (e.g.: size, grade, laterality). A cancer patient may appear in the Registry multiple times, but each record is a new instance of cancer, not a reoccurrence. It is possible for a new type of cancer to occur at the same site. For example, a patient may have two instances of breast cancer recorded, where the tumour is of a different structure each time.

For a list of variables contained in the Cancer Registry dataset and the data quality aspects investigated in Lix et al. (2016), please see Appendix Table 2.2: Valid, Invalid, Missing, and Outlier (VIMO) Table for Manitoba Cancer Registry Data, 1984-2011 in the deliverable.

For more information about the data quality aspects of the Cancer Registry, see the Cancer Registry Data Quality section below.

Cancer Site

Cancer site indicates the part of the body where the cancer originated; the primary site, regardless of metastasis. International Classification of Diseases for Oncology, 3rd edition (ICD-O-3) codes are used to catalogue cancer tumours by site and type. These codes may appear similar to ICD-10-CA diagnosis codes, but there are subtle differences that allow for a more precise classification of cancer. The Cancer Registry dataset also contains a cancer site variable which describes/categorizes the cancer site (e.g.: brain, lung and bronchus).

ICD-O-3 codes have two parts:


1. Topography axis (cancer site). Topography classifies cancer based on part of the body the primary tumour originated from, such as lung or brain.
   
2. Morphology axis (histology/behaviour). The first four digits is the histology or tumour cell type and the fifth digit is the behaviour (benign, in situ, uncertain or malignant).

Additional Information


• For a list of the frequency (%) of patients diagnosed with cancer by cancer site and sex, for 1984-2011, see Appendix Table 2.11 in the deliverable.
  
• For information on the specific cancers investigated in Lix et al. (2016), including the ICD-O-3 topography and morphology codes used to identify each cancer, see the Cancer Site glossary term.

Cancer Stage

Cancer stage indicates the severity of an individual's cancer at the time of diagnosis. Information about cancer stage is available in the Manitoba Cancer Registry dataset from January 1, 2004 forward. Stage information is captured and coded according to the latest national standard - currently collaborative stage. This includes detailed information about the primary tumour, regional lymph nodes and metastasis.

The most widely used stage reporting system, and the system used in Manitoba, is TNM (Tumour, Node, Metastasis), based on the American Joint Committee on Cancer (AJCC) guidelines. TNM is not static; it changes over time based on new developments in cancer prognosis so that it can remain relevant to both clinicians and patients. The TNM system considers:


1. Tumour (T) Stage: size of primary tumour and extent of tumour(s)
   
2. Node (N) Stage: whether the cancer has spread to adjacent lymph nodes; and
   
3. Metastasis (M): whether the cancer has spread from the primary site to other parts of the body

For data collected from 2004 to 2017, a summary cancer stage is calculated and recorded in the Cancer Registry, based on the detailed tumour, node and metastasis data collected. Summary cancer stage is likely the simplest way to categorize severity of cancer. However, in some cases summary cancer stage has sublevels such as IIa, IIb, etc., so it may need to be further truncated to get summary stage values I, II, III and IV. In Lix et al. (2016), cancer stage was collapsed into summary cancer stage I (least severe) to stage IV (most severe) and unknown stage.

For data collected from 2018 forward, the proper terminology is stage group rather than summary stage. These terms have different meanings starting in the AJCC 8th edition.

In the Manitoba Cancer Registry, summary stage / stage group is coded using the following variables:


• AJCC6 - summary stage following the AJCC 6th edition guidelines for data from 2004-2009;
  
• AJCC7 - summary stage following the AJCC 7th edition guidelines for data from 2010-2017; and
  
• PATH_STAGE (pathological stage), CLINICAL_STAGE (clinical stage), or PT_STAGE (post therapy stage) following the AJCC 8th edition guidelines for data from 2018 onwards, and AJCC 9th edition guidelines for Cervix cases since 2021.
  
  NOTE: There is no single "stage group" variable currently available in the Cancer Registry for data from 2018 forward (using the AJCC 8th and 9th edition guidelines). SAS® code was developed by CancerCare Manitoba that provides an algorithm to determine the most definitive stage group value from the PATH_STAGE or CLINICAL_STAGE variables presented above. Please see the SAS code and formats section below (internal access only) for an example of the TNM cancer staging system algorithm that follows the AJCC 8th and 9th edition guidelines, including the SAS formats and SAS code to calculate the stage group value.

IMPORTANT NOTE: The different cancer staging systems / editions are not directly comparable, so please take this into consideration if your research plans are to use cancer stage as a predictor in a statistical model.

It is also important to understand that not all cancers in the Cancer Registry data contain stage information. The reasons for this include:


• the tumour is not accessible for biopsy;
  
• some cancers, by their nature, cannot be staged; and
  
• data prior to January 1, 2004 did not record cancer stage information.

Additional information


• For information on the percent of cancer stage information by cancer site in the Manitoba Cancer Registry from Lix et al. (2016), see Appendix Table 2.3 (2004-2009) and Table 2.4 (2010-2011) in the deliverable.
  
• For information on the summary cancer stage (%) by cancer site in the Manitoba Cancer Registry (2004-2011) from Lix et al. (2016), see Appendix Table 2.5 in the deliverable.

2. The Cancer Treatment Dataset

The Cancer Treatment dataset contains information on the cancer treatment provided to patients in the Cancer Registry database. Treatment data is "linked" to the Cancer Registry data using a scrambled Personal Health Identification Number (PHIN) and tumour ID. Each new cancer instance has a unique tumour ID. There can be multiple records for each cancer instance, indicating various types of treatment. Each treatment record has a date, treatment date status (i.e.: complete, day unknown, day and month unknown, and date unknown) and a procedure/intervention code. Treatments are coded using either procedure codes from the International Classification of Diseases, 9th Revision, with Clinical Modifications (ICD-9-CM) for the time period 1984-2004, or intervention codes from the Canadian Classification of Health Interventions (CCI) for the time period January 1, 2005 forward.

For a list of variables contained in the Cancer Treatment dataset and the data quality aspects investigated in Lix et al. (2016), please see Appendix Table 2.6: Valid, Invalid, Missing, and Outlier (VIMO) Table for Manitoba Cancer Treatment Data, 1984-2011 in the deliverable.

For more information about the data quality aspects of the Cancer Registry, see the Cancer Registry Data Quality section below.

Types of Cancer Treatment

Treatments for specific types of cancer (bladder, breast, chronic lymphocytic leukemia, colorectal, lung and prostate) were investigated in Lix et al. (2016). Treatments were divided into the following four broad categories: surgical intervention, chemotherapy, hormone therapy and radiation therapy. In August 2024, an additional treatment category, Immunotherapy, was added to this list. Each category is listed below, with links provided to a glossary term definition, and a list of the ICD-9-CM and/or CCI codes used to identify each type of cancer treatment:


1. Surgical Intervention
   
   
   • ICD-9-CM codes: - any intervention in 0.1.xx–86.xx, excluding:
     
     • 34.92 - injection into thoracic cavity;
       
     • 38.00 - incision of vessel at unspecified site;
       
     • 38.99 - other puncture of vein;
       
     • 57.33 - closed [transurethral] biopsy of bladder;
       
     • 85.12 - open biopsy of breast
       
     • 85.6 - mastopexy
     
     
   • CCI codes: - any physical/physiological therapeutic intervention in 1.xx.xx.^^, excluding:
     
     • 1.xx.00.^^ –1.xx.58.^^
       
     • 1.xx.70.^^ –1.xx.86.^^
       
     • 1.FU.59.HA-V1 - destruction, thyroid gland, using percutaneous (needle) approach and radioactive pharmaceutical agent [e.g. I-131, radioiodine]
   
   
2. Chemotherapy
   
   
   • ICD-9-CM codes:
     
     • 99.25 - injection or infusion of cancer chemotherapeutic substance
     
     
   • CCI codes:
     
     • 1.ZZ.35.CA-M0 - pharmacotherapy, total body, per orifice (oral) approach, using antineoplastic agent NOS
       
     • 1.ZZ.35.CA-M9 - pharmacotherapy, total body, per orifice (oral) approach, using combination [multiple] antineoplastic agents
       
     • 1.ZZ.35.HA-M0 - pharmacotherapy, total body, percutaneous approach [intradermal, intramuscular, intravenous, subcutaneous], using antineoplastic agent NOS
       
     • 1.ZZ.35.HA-M9 - pharmacotherapy, total body, percutaneous approach [intradermal, intramuscular, intravenous, subcutaneous], using combination [multiple] antineoplastic agents
       
     • 1.ZZ.35.YA-M0 - pharmacotherapy, total body, route NEC [transdermal, etc.], using antineoplastic agent NOS
       
     • 1.ZZ.35.YA-M9 - pharmacotherapy, total body, route NEC [transdermal, etc.], using combination [multiple] antineoplastic agents
   
   
3. Immunotherapy
   
   
   Note: In Lix et al. (2016), the following CCI codes were listed under Chemotherapy treatment, but since January 1, 2013 are now coded as Immunotherapy treatment.
   
   
   • CCI codes:
     
     • 1.ZZ.35.CA-M5 - pharmacotherapy, total body, per orifice (oral) approach, using other antineoplastic agents
       
     • 1.ZZ.35.HA-M5 - pharmacotherapy, total body, percutaneous approach [intradermal, intramuscular, intravenous, subcutaneous], using other antineoplastic agents
       
     • 1.ZZ.35.YA-M5 - pharmacotherapy, total body, route NEC [transdermal, etc.], using other antineoplastic agents
   
   
4. Hormone Therapy
   
   
   • ICD-9-CM codes:
     
     • 99.24 - injection of other hormone
     
     
   • CCI codes:
     
     • 1.ZZ.35.CA-M6 - pharmacotherapy, total body, per orifice (oral) approach, using endocrine therapy
       
     • 1.ZZ.35.HA-M6 - pharmacotherapy, total body, percutaneous approach [intradermal, intramuscular, intravenous, subcutaneous], using endocrine therapy
       
     • 1.ZZ.35.YA-M6 - pharmacotherapy, total body, route NEC [transdermal, etc.], using endocrine therapy
   
   
5. Radiation Therapy
   
   
   • ICD-9-CM codes:
     
     • 92.2–92.29 - therapeutic radiology and nuclear medicine
     
     
   • CCI codes:
     
     • 1.FU.59.CA-V1 - destruction, thyroid gland, using oral approach radioactive pharmaceutical agent [e.g. I 131, radioiodine]
       
     • 1.FU.59.HA-V1 - destruction, thyroid gland, using percutaneous (needle) approach and radioactive pharmaceutical agent [e.g. I-131, radioiodine]
       
     • 1.OA.59.DA-AW - destruction, liver, endoscopic [abdominal] approach, using radiofrequency
       
     • 1.ZZ.35.HA-V1 - pharmacotherapy, total body, percutaneous approach [intradermal, intramuscular, intravenous, subcutaneous], using radioactive pharmaceutical agent
       
     • x.xx.26.^^ - brachytherapy on any section of the body
       
     • x.xx.27.^^ - radiation on any section of the body

For information on the demographics, diagnosis and treatment characteristics of the cancer cohort used in Lix et al. (2016), see Table 4.1: Demographic, Diagnosis, and Treatment Characteristics of Cancer Cohort in the deliverable.

Treatment Dates

The treatment date that is recorded in the Cancer Treatment data varies by the type of treatment, including:


• for surgical interventions, the date of surgery is recorded as the treatment date;
  
• for chemotherapy, immunotherapy and hormone therapy, the start date of treatment is recorded for that calendar year. If the chemotherapy, immunotherapy or hormone therapy extends over the calendar year, then another treatment record is generated with January 1st as the treatment date; and
  
• for radiation therapy, the start date of each course of radiation therapy is recorded as the treatment date.

Cancer Registry Data Quality

As part of the research completed by Lix et al. (2016), they investigated the data quality of the Manitoba Cancer Registry data using the MCHP Data Quality Framework. This involves measures of data quality at the time of data acquisition and project-specific data quality measures. For more information on the MCHP Data Quality Framework, please see the MCHP Data Quality Framework glossary term and read the related links.

A summary of the findings of the Manitoba Cancer Registry data quality assessment from this research includes:


• application of the MCHP Data Quality Framework to the Manitoba Cancer Registry data revealed a high degree of completeness of the data; there were very few data fields with missing or invalid observations, indicating that the data are thoroughly checked prior to release. The research found that not all treatment data was entered for 2005 due to a change in coding from ICD-9-CM to CCI.
  
• there was 100% linkage of patient–specific identification variables between the Manitoba Cancer Registry data and the Manitoba Health Insurance Registry, indicating linkage between these data sources is excellent; and
  
• the Manitoba Cancer Registry data undergo systematic quality evaluations prior to their integration into the Canadian Cancer Registry and in order to achieve certification from the North American Association of Central Cancer Registries. Thus, the data are of very high quality.

For more detailed information on the data quality assessment of the Manitoba Cancer Registry database found in this research, please see:


• Chapter 2: Applying MCHP's Data Quality Framework to the Manitoba Cancer Registry; and
  
• Appendix 2: Data Quality Report for Manitoba Cancer Registry Data in the MCHP Population Health Research Data Repository

Additional project-specific data quality aspects were investigated in this research. Please read the following concepts for additional information:


• Cancer Diagnoses Validity / Agreement In Administrative Health Data; and
  
• Location of Residence (Postal Code) Agreement in Administrative Data