HemOnc.org Wiki: A Free Resource to Support Oncology Pharmacists

The systemic treatment of cancer encompasses a wide range of therapies, including cytotoxic agents, biologics, immunotherapies, and antibody–drug conjugates.¹ These are frequently administered as multiagent regimens across various clinical contexts.² Oncology pharmacists are integral members of the care team in ambulatory oncology clinics and inpatient settings, and they play a critical role in ensuring that oncological regimens are delivered safely and effectively. Oncology pharmacists not only help design complex therapeutic plans that align with published literature and provider preferences, they also tailor these plans to meet the unique patient needs for individualized dosing and supportive care to prevent or mitigate adverse events.³ Oncology pharmacists also play a role in therapeutic decision-making.^4,5

The complexity of cancer treatments, combined with the demands of the pharmacist’s role, present major challenges to ensuring that cancer care is safe and state-of-the-art. The volume of updates to informational resources necessary to stay current restricts the usefulness of traditional sources of knowledge, such as textbooks and other compendia.^6,7 In addition, details such as dosing variations and sequencing, adverse events, and indications by disease subtypes or patient profiles are often buried or missing in traditional knowledge sources. Further, many internet-based resources are behind paywalls and inaccessible to clinical users in resource-constrained settings.

In response to these challenges, HemOnc.org was launched in 2011 as a free and continually updated knowledge source focused on systemic treatment regimens and supportive care across all hematology and oncology domains.^8,9 HemOnc.org aims to provide consistently structured, evidence-based, and up-to-date information that is not only clinically relevant but also immediately usable to everyone, including pharmacists, other healthcare providers, and patients.

HemOnc.org Wiki

HemOnc.org is a crowdsourced wiki built with MediaWiki, the software that powers Wikipedia. The platform is ad-free and does not require registration to access the content. To ensure the clinical rigor of HemOnc.org, editing privileges must be requested and are open only to healthcare professionals and trainees who are in clinical training programs or under the direct supervision of members of the editorial board.

The editorial board currently consists of more than 60 members, who oversee the content and enforce quality standards. The scope of the editorial board was expanded in 2024 to include clinical pharmacists, the majority of whom have attained Oncology Pharmacy Specialty Certification (BCOP).¹⁰ The editorial process is supported by a detailed style guide, an editing tutorial, and inclusion criteria, which are listed under the “How to contribute” heading among the navigation links on the left side of every page.

Site Organization

HemOnc.org presents treatment details in a structured, hierarchical format. As of June 21, 2025, the wiki contains 5513 treatment regimens across 395 pages, covering 192 distinct cancers and blood disorders.¹¹ Each cancer type has at least 1 dedicated page, with treatment regimens organized by clinical context, eg, neoadjuvant, adjuvant, or first-line metastatic settings. For treatments guided by biomarker status (eg, treatments for hormone receptor–positive breast cancer), there are dedicated subpages. Clinical practice guidelines from professional societies, such as the American Society of Clinical Oncology (ASCO), European Society for Medical Oncology, and the National Comprehensive Cancer Network (NCCN), are referenced and externally linked on the disease-specific pages.

Individual regimens follow a consistent template that includes drug components, dosing schedules, routes of administration, number and length of cycles, and links to supporting literature (Figure 1). With few exceptions, regimens are supported by prospective clinical trial evidence. Key trial details, including trial phase and primary outcomes, are presented in tables; pivotal trials supporting regulatory approval are also included. Standardized statistical language and coloring schemes are used to convey whether a trial was positive, negative, or borderline. The available regimen information also includes older treatments that may no longer be in routine use but remain accessible in the literature, offering additional context to interested users.

Pharmacist-Centered Content

HemOnc.org has several pages that are highly relevant to oncology pharmacists, many of which are among the most-visited individual pages on HemOnc.org.

Vesicant/irritant chemotherapy
This page organizes anticancer agents according to their potential to cause local tissue injury (Figure 2). It categorizes agents and drug classes as vesicants, irritants, neutrals, inflammation-producing, and exfoliants. Appropriate use of pharmacologic antidotes (eg, dexrazoxane), including relevant administration techniques and dosing protocols, are provided. Recommendations are externally linked to original sources, which enable clinicians to investigate discrepancies with local practice and to interpret evidence in context.

Antiemesis
This page categorizes anticancer agents by their emetogenic risk based on criteria from major oncology guidelines, including NCCN, ASCO, and the Multinational Association of Supportive Care in Cancer. It also provides recommended antiemetic prophylaxis for each risk level, which helps guide evidence-based prevention of chemotherapy-induced nausea and vomiting (Figure 3).

Drug pages
Each drug page provides standardized nomenclature (code, generic, and trade names), pharmacologic classification, mechanism of action, and links to cancer types for which the agent is used (Figure 4). All FDA-approved labels for systemic anticancer agents are included, and many pages include labels from additional regulators, such as the European Medicines Agency and the Pharmaceuticals and Medical Devices Agency of Japan. Links to centralized prescribing information documents are provided, and locally backed-up prescribing information documents are also made available, because the external URLs often break over time. Special considerations such as Risk Evaluation and Mitigation Strategies programs and pharmacogenomic testing recommendations (eg, for DPYD genotyping prior to starting fluoropyrimidines) are provided on the relevant pages. In practice, these pages are especially useful during regimen verification, particularly when assessing alternative dosing strategies, route modifications, or off-label use.

Global Reach and User Engagement

HemOnc.org has received more than 4 million visits since its launch in 2011, with users from more than 219 countries and territories, according to Google Analytics. At least 76 countries have had in excess of 1000 unique visitors, and 30 countries have had more than 10,000 visitors each. Current traffic averages 25,000 to 35,000 sessions per month, and approximately half of these are returning users. These numbers are likely an underestimate, because those who use tracker blocking are not included in web traffic data by Google Analytics. Due to the free and open nature of HemOnc.org, the exact characteristics of users are unknown; however, past surveys have indicated that up to 50% of users are clinical pharmacists.

HemOnc.org has partnered with major research networks and organizations, including the American Association for Cancer Research, the National Cancer Institute, the Observational Health Data Sciences and Informatics program, and eviQ (Australia). In a new 2025 initiative, weekly content updates are distributed through the HemOnc.org Google Groups mailing list. This hybrid mailing list and online group discussion board is free and available by emailing This email address is being protected from spambots. You need JavaScript enabled to view it..

Join HemOnc.org as a Contributor

As frontline experts in chemotherapeutic safety and supportive care, oncology pharmacists are not only key users but also ideal contributors to HemOnc.org, which relies on community input and contributions. The expertise of oncology pharmacists in drug preparation, administration, and adverse-event management makes them well-suited to flag errors in existing content and to contribute fresh content related to chemotherapy safety and supportive care. Because pharmacists can readily identify inconsistencies or discrepancies in treatment protocols, their insights can improve the accuracy and utility of HemOnc.org. Pharmacists who want to contribute can apply for editing privileges through a short application process on the website. Because HemOnc.org is free, open-access, and requires no subscription or institutional affiliation, all pharmacists can access the same high-quality, up-to-date information, references, and pharmacy tools regardless of institutional resource limitations. In the oncology pharmacy profession, even small errors in timing or dosage may lead to serious adverse events.¹² By participating in and promoting the efforts of HemOnc.org, pharmacists can help shape a resource that supports the needs of oncology care across many different settings. For additional information, users are encouraged to contact us via email at This email address is being protected from spambots. You need JavaScript enabled to view it..

Conclusion and Future Plans

In clinical oncology practice, accurate dosing and scheduling of chemotherapeutic drugs are essential to ensure safe and effective cancer treatment. Most regimens are multidrug combinations that need to be given in precise sequences over several cycles; thus, oncology pharmacists need up-to-date, clear, and accessible information to correctly plan regimens. Access to a reliable resource at the point of care can help ensure that complex details are followed as intended.

With the HemOnc.org foundation, some of our future goals include developing tools to introduce visual safety flags for regimens involving narrow therapeutic index drugs, informed by real-world safety data such as the FDA Adverse Event Reporting System. These alerts may help pharmacists to quickly identify therapies with a higher risk of adverse events. Another priority is to flag regimens that lack adequate representation of specific patient populations, such as older adults, racial and ethnic minorities, or patients with comorbidities. In addition, we have begun working on dedicated pages for hepatic and renal dose adjustments for oral medications, beginning with breast cancer and multiple myeloma. These additions will help pharmacists make safer and more informed treatment decisions.

Acknowledgement

The authors would like to acknowledge the valuable work of their team members in building and maintaining HemOnc.org: Angel Liu, PharmD, University of Washington, Fred Hutchinson Cancer Center, Seattle, WA, USA; Elizabeth J. Davis, MD, Vanderbilt University Medical Center, Nashville, TN, USA; Gaurav Goyal, MBBS, University of Alabama at Birmingham, Birmingham, AL, USA; Irbaz Bin Riaz, MD, PhD, MS, Mayo Clinic, Phoenix, AZ, USA; Laura Roccograndi, PharmD, BCOP, University of Washington, Fred Hutchinson Cancer Center, Seattle, WA, USA; Liang Wayne, MD, Children's Hospital of Atlanta, Atlanta, GA, USA; Rachel Feaster, PharmD, BCOP, BCPS; Samuel M. Rubinstein, MD, MS, University of North Carolina, Chapel Hill, NC, USA.

References

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11. HemOnc.org Fact Sheet. Accessed June 5, 2025. File:HemOnc.org Fact Sheet.pdf | HemOnc.org - A Hematology Oncology Wiki
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