Cancer Research, The Philippine Population-Based Cancer Registry and The Quest for Philippine Cancer Survival Information

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Corazon A Ngelangel and Rachel Marie B Rosario

In most cancer research proposals and publications, the cancer burden is emphasized at the beginning and the end—the very reason for their existence. Inside the proposals and publications are "explorations of the complexity and many facets of oncology care and cancer control from diverse perspectives."

SEER2 has defined a cancer registry as an information system specifically designed for the collection, storage, and management of data on individuals with cancer. These registries, whether population-based or hospital-based, play a pivotal role in cancer surveillance, providing crucial insights into our progress in reducing the cancer burden.

WHO-IARC3 indicated that population-based cancer registries (PBCR) “describe the extent and nature of the cancer burden in the community and assist in the establishment of public health priorities, are used as a source of material for etiological studies, and help in monitoring and assessing the effectiveness of cancer control activities." PBCRs record all new cases in a defined population (most frequently a geographical area such as Metro Manila), emphasizing epidemiology. PBCRs are designed to determine cancer patterns among various populations or sub-populations, monitor cancer trends over time, guide the planning and evaluation of cancer control efforts, help prioritize health resource allocations, and advance clinical, epidemiological, and health services research.4 Analysis of the routine data on cancers in a PBCR remains an essential component in understanding the epidemiology of cancers in a limited resource setting, and routine data of the cancer registry can be used for retrospective research (inferred from incidence, mortality, and survival rates) and exciting cases to report. New trends or findings from cancer registries would incite prospective research.

Currently, the Philippines boasts two high-quality PBCRs – the Department of Health Rizal Cancer Registry (DOH-RCR) and the Philippine Cancer Society Manila Cancer Registry (PCS-MCR), both launched in 1974 and 1983, respectively. These registries, established through the Department Circular No. 200 s. 1974 and Ministry Circular No. 126-A s.1983, play a crucial role in providing essential public health information such as cancer incidence and prevalence. They are a testament to the Philippines' commitment to cancer research and control, and their importance cannot be overstated.

Philippine PBCRs gather cancer-related data from hospitals and local civil registries through both passive and active methods. This involves visiting various hospital departments and the tumor registry for cancer-related data. However, the implementation of the Data Privacy Act in 2012 posed a challenge to this data collection process. The Act classifies health information as sensitive personal data and prohibits its processing. The National Integrated Cancer Control Act (NICCA)

and its Implementing Rules and Regulations (IRR) provide a solution by establishing a national cancer registry and monitoring system through PBCRs, thereby superseding the DPA.

Population-based survival data requires the entry of the last known status of the patient if alive, dead, lost to follow-up, or vital status unknown. The vital status information can be obtained through active or passive procedures. Active follow-up consists of regular checking of the vital status of each cancer patient by the physician, hospital, or through home visits. Passive follow-up refers to regularly checking the vital status of all registered patients from information provided by registries, herewith the Local Civil Registry (LCR) and the Philippine Statistics Authority (PSA) national registry.

The LCR is a data source with a death registry containing the certificates of those who died in the locality. DOH-RCR and PCS-MCR PBCRs utilize data collection forms for hospital case-finding and death certificates in LCRs. Cancer registry clerks collect all data and bring them back to the PBCR office for cross-checking, abstracting, coding, and encoding.

Each city and municipality in the Rizal and Manila region has its own LCR. The LCR office receives the accomplished death certificates of people who died there. Physicians in charge file death certificates and include the full name, age, sex, place of death, date of death, and probable cause. The LCR processes, files, and endorses the Certificates of Death to the PSA for certification and printing. The PBCR's official link with the PSA is essential for collecting survival status information. In the case of local migration, the death of index patients outside Manila and Rizal will not be reflected in the LCRs.

The PSA is the central statistical authority of the government, established in 2013 pursuant to Republic Act 10625, which reorganized and strengthened the Philippine statistical system. It is the national depository for the birth, marriage, and death certificates of the Philippine citizenry.

There has been no official collaboration between the PSA and the DOH-RCR and PCS-MCR PBCRs. These PBCRs’ previous population-based survival analysis utilized a combination of expensive and labor-intensive active and passive follow-up procedures. In contrast, obtaining death certificates from the PSA will reliably identify all registered cancer patients' deaths. All patients not identified as deceased would be alive.

Just last 29 November 2023, DOH Cancer Control Division, Epidemiology Bureau, Knowledge Management & Information Systems, PSA, National Data Privacy Commission, Philippine Cancer Center, DOH-RCR, PCS-MCR, and WHO came together to resolve this obstacle to the PBCRs in the country. An official process was found to already exist for requests on PSA data through a formal Data Sharing Agreement (DSA), exemplified by linkages with PhilHealth, the Philippine National Police, and other government agencies at no cost. A supporting mandate of the requesting agency is a prerequisite for the collaboration. NICCA Section 28 mandates the establishment of a National Cancer Registry and Monitoring System, which includes the PBCR. Thus, collecting relevant health information is allowed, provided it is to establish the required National Cancer Registry and complies with the NICCA and its IRR. With official data linkage to the PSA, the PBCRs would easily access target population survival data in the country.

Hospital-based cancer registries (HBCR) maintain data on all patients diagnosed and treated for cancer at a particular health facility, focusing on clinical care and hospital administration.3 More in-depth information on the clinical profile of the cancer cases, like the extent of cancer disease and initial treatment, are mainly within the purview of an HBCR rather than a PBCR; the clinical outcome of the patient, such as survival, is significantly related to the extent of cancer disease and the initial treatment. The HBCR complements the PBCR. Such HBCRs can be culled out of the hospital's medical records, capturing only those with a cancer diagnosis more quickly if the hospital has electronic medical records. It would be best if hospitals (wherein the population-based registry data are being collected) had hospital-based cancer registries to feed complete pertinent data to the population-based cancer registry.

Cancer registries are research gold mines. The re-launch of the Philippine Journal of Oncology by the Philippine Society of Oncologists in 2024 is laudable. We were much awaited to worthwhile share for a lifetime through publications our many thoughts, experiences, knowledge, practices, and processes on cancer management and control in the hospitals and the community, which indeed would “center on several viewpoints that illuminate essential facets of patient welfare, therapeutic approaches, and healthcare infrastructures, and provide distinctive perspectives on the intricacies encountered by medical professionals, patients, caregivers, and policymakers in diverse facets of cancer treatment and control”1.

REFERENCES

1. Dr. Susano Tanael, Editor-In-Chief of PJO, on Themed issue of PJO, Sept 2024.

2. A cancer registry is an information system designed for the collection, storage, management, and analysis of data on persons with cancer [Internet]. National Cancer Institute Surveillance, Epidemiology, and End Results Program. [cited 2023 Dec 1]. Available from: https://seer.cancer.gov/registries/cancer_registry/

3. Cancer registry [Internet]. International Agency for Research on Cancer. [cited 2023 Dec 1]. Available from: https://publications.iarc.fr/Advanced-Search?q=cancer+registry

4. Hospital-based registries [Internet]. National Cancer Institute Surveillance, Epidemiology, and End Results Program. [cited 2023 Dec 1]. Available from: https://training.seer.cancer.gov/registration/types/hospital.html

5. Krishnatreva M. Epidemiological research on cancers by cancer registries: A viewpoint. South Asian J Cancer. 2015 Jan-Mar;4(1):50.

CITATION

Ngelangel CA, Rosario RMB. Cancer research, the Philippine Population-Based Cancer Registry and the quest for Philippine cancer survival information. Philipp J Oncol. 2025;1(1):3–5. Available from: https://www.philsoconc.org/post/cancer-research-the-philippine-population-based-cancer-registry-and-the-quest-for-philippine-cancer