This qualitative content analysis is based on a nonparticipant observational study of 5 French online discussion forums over a 10-year period (2015‐2025). It represents the first phase of a broader project, titled HORMONO+, examining the information needs, expectations, and lived experiences of women undergoing extended AET, with the aim of identifying strategies to improve follow-up care. In this initial phase, we adopted a netnographic approach, a qualitative method pioneered by Kozinets [40] derived from ethnography, which is particularly well suited for exploratory research as it allows nonintrusive observation of users’ online social interactions and experiences, offering rich insights into shared information and a deeper understanding of behaviors in digital contexts [41]. We used the SRQR (Standards for Reporting Qualitative Research) checklist to ensure completeness and transparency in reporting our qualitative findings.

In February 2025, we conducted a search on Google to identify online discussion threads related to extended AET, which led to the identification of 5 French-speaking, France-based forums. In line with current best ethical practices in internet forum–based research, we chose not to disclose the names of the forums [42-44] and, instead, assigned each forum a letter of the alphabet. These forums were hosted on general health-related websites (forum A), platforms dedicated to chronic diseases and cancer (forums B and C), or were specifically focused on breast cancer (forums D and E).

The structure of discussion threads varied across forums. In some (A and C), users could freely create discussions and post messages on a wide range of breast cancer–related topics without strict categorization. Other forums (B, D, and E) featured a more organized layout, especially forums D and E, where discussions were divided into predefined thematic categories (eg, chemotherapy, radiotherapy, and complementary treatments). In forum E, each thematic category contained multiple discussion threads, each addressing a specific topic. In forum D, however, all messages related to a given theme (eg, hormone therapy) were grouped into a single, often very large, discussion thread which could contain thousands of posts. For simplicity, we referred to each thematic category as a “discussion thread” (Figure 1).

Some forums were moderated by a qualified health care professional (C) or by nonprofessional moderators (B), some of whom had personal experience with breast cancer (D and E). Moderator involvement varied from proactive engagement to retrospective oversight. Forum guidelines included recommendations regarding personal responsibility, confidentiality, and security (eg, avoiding disclosure of personal information), as all messages were publicly accessible, except in forum B, where registration was required to access the full content of all messages.

Although some websites reported high traffic (more than 4 million unique visitors per month in 2025 for the website hosting forum A) and gathered thousands of members (more than 3000 for forum B), traffic volume was not the primary selection criterion. Instead, the decision to include different types of forums was driven by the aim to ensure greater diversity and capture a variety of user profiles and experiences. While users’ geographical locations were not always specified, the majority appeared to be based in France, although posts from French women living abroad were also identified.

For each forum studied, we first conducted nonparticipant observations to better understand forum dynamics and identify discussion threads relevant to our research topic. Data were collected in March 2025, from discussion threads in forums A-E addressing AET, by either directly mentioning the term or referring to specific treatments (TAM, anastrozole, and letrozole) using either their generic or brand names, over a period spanning a decade (2015-2025). A total of 191 discussion threads were identified based on these keywords, comprising 6064 messages during the specified period. Forty-one threads specifically discussing extended AET were retained (Figure 2).

We then included posts from women, either pre- or postmenopausal, undergoing AET for ER+ breast cancer, with TAM or an AI, meeting the following inclusion criteria: (1) having received AET for at least 5 years, (2) meeting medical criteria for extending AET beyond 5 years, (3) eager to continue AET beyond 5 years even in the absence of medical indication, and (4) discussing AET extension regardless of treatment duration. Posts from family members discussing treatment extension for a relative were also included. We excluded posts from patients with metastatic breast cancer and men diagnosed with breast cancer. A total of 188 relevant messages posted by 105 women were included in the analysis.

All relevant posts were copied and pasted into an Excel spreadsheet and organized thematically to provide an overview of key discussion areas. For each message, the forum identifier (A, B, C, D, or E), the thread title, the message URL, and the publication date were systematically recorded. All relevant posts were copied and thematically organized to provide an overview of key discussion areas with the forum identifiers (A-E), the thread title, URL, and publication date.

Some elements of the thematic analysis derived from netnography [41], including the identification and selection of online communities, data collection, analysis, and interpretation, were integrated with Braun and Clarke’s approach [45] whose six steps were implemented as follows: (1) identification of discussion threads, reading of posts, and note-taking (GC); (2) development of initial codes using both inductive (narrative-based) and deductive (literature-informed) approaches on 20% of the dataset (GC and SDM); (3) generation of potential themes and subthemes through team discussion (GC, SDM, and JM); (4) refinement and revision of themes and subthemes (GC); (5) consensus on the final thematic framework (GC, SDM, and JM); and (6) independent coding and analysis by 1 researcher (GC).

The research project titled “HORMONO+” was approved by the ethics committee of Aix-Marseille University at its meeting on February 27, 2025 (IRB00014113, reference no.: 2025-02-27-012). No informed consent was sought, as the messages posted by forum users were publicly available and there was no direct interaction with users in this nonparticipant observational study. To preserve anonymity, forum pseudonyms were replaced with generic female first names, and any identifying details were removed. Forum posts were reworded for publication to maintain their meaning while preventing traceability to individual users. No financial compensation was provided.

Women’s reactions to extended AET vary depending on when they received the information. Some expressed surprise when the duration was revised midcourse, while others were informed from the outset that it could last up to 10 years and had already factored in this possibility.

Among women on the forums who do not medically require AET extension beyond 5 years, stopping treatment brings ambivalent feelings. Joy and relief are mixed with a sense of unease, expressed in their discourse through phrases such as: “I’m walking without a safety net,” “I won’t feel protected anymore,” or “We’re never truly reassured or at peace” or even referring to their treatment as “an old friend.”

Some women and their families report experiencing or observing physical and psychological symptoms following treatment discontinuation. Emotional distress is described with expressions such as “a fear that only leaves me when I sleep,” “completely shaken and destabilized,” and “sleep problems, anxiety.” A potential link between these feelings and the perceived loss of therapeutic protection deserves further investigation.

In addition to concerns about these symptoms, the distress caused by the lack of medical follow-up or guidance is also highlighted.

Several women express a sense of regret at not being able to continue AET, varying in intensity, and sometimes even conveyed with a touch of humor.

Beneath the regret, deeper introspection sometimes emerges, focused on managing future regrets and perceived responsibilities.

Occasionally, the medical decision to limit treatment to 5 years sparks genuine confusion, accompanied by feelings of injustice and a sense of lost therapeutic opportunity. This is the sentiment expressed by Marie, who has made extending treatment her cause (Textbox 1).

The decision to accept or refuse extended AET appears to be influenced by a combination of interrelated factors, including fear of recurrence, beliefs and attitudes toward AET, the patient-HCP relationship, and side effects.

Our study provides novel, comprehensive insights into how women in France engage with online forums to share information, expectations, and experiences regarding extended AET. While extensive quantitative and qualitative research has examined determinants of adherence during the first 5 years of treatment [7], qualitative studies focusing on women undergoing extended AET remain limited. This study addresses this gap by exploring women’s information needs regarding extended AET, the factors influencing their decision-making, and how they share experiences and manage side effects over time, an issue of growing importance as an increasing number of women are now prescribed extended therapy, highlighting the value of online forums as a rich source of information for a deeper understanding of these dynamics.

Our findings suggest a proactive approach to gathering knowledge from both biomedical and nonexpert sources. However, difficulties in interpreting information perceived as complex or inconsistent may lead to misconceptions, underscoring the critical need for clear, reliable, and accessible information, especially regarding the risk-benefit balance of extending AET.

Women’s reception of information about extended AET appeared closely linked to the timing of its disclosure. Those who were initially prescribed a 5-year protocol occasionally expressed surprise or disappointment, while women informed from the outset about potential treatment extension seemed more likely to have integrated this possibility. Regardless of when the information was conveyed, 3 patterns of decision-making typically emerged among forum participants: acceptance, hesitation, or refusal. Interestingly, for women not medically required to continue AET beyond 5 years, discontinuation was sometimes accompanied by ambivalent feelings—relief mixed with a sense of lost protection. Some even reported feelings of injustice or the perception of being denied a potential therapeutic opportunity.

The time frame of our data collection (2015‐2025) showed that reasons for continuing, discontinuing, or being undecided about extended AET may evolve over time, influenced by individual circumstances and various factors. These include fear of cancer recurrence and prioritizing survival over immediate quality of life, experience and management of side effects, and trust in medication effectiveness. These factors have also been identified in previous research on persistence with AET over both a 10-year period [39,46] and within the standard 5-year treatment regimen [25]. Regarding side effects, our data indicate that their presence alone did not necessarily result in treatment discontinuation [39]. Instead, this seemed linked to women’s self-efficacy to manage symptoms [47], along with the use of both pharmacological interventions (eg, antidepressants) and nonpharmacological approaches (acupuncture, yoga, meditation, and physical activity), some of which are supported by the best available evidence [48].

The feeling of being insufficiently informed by HCPs about the benefits and risks of extended AET, especially regarding side effects, or receiving conflicting information from physicians was another important factor influencing both decision-making and the overall experience of extended AET. This aligns with findings from research on extended AET [39,46] and the standard 5-year regimen [7,25]. As shown in our study, even among women who have been on treatment for several years, the perceived lack of clear, specific, and personalized information about extended AET may lead some to seek information independently [49] or turn to online discussion forums for guidance [26,39], including in their decision-making process. Exploring data from online health discussions is thus particularly valuable for capturing patient perspectives —especially as patients with breast cancer tend to engage more actively in online forums than those with other cancer types [50,51].

Our study confirms that these spaces are relevant for sharing knowledge about extended AET, reflecting on interactions with HCPs, and exchanging advice and coping strategies—consistent with previous research [52]. The importance of online communities in sharing information and improving the emotional well-being of patients with breast cancer has been demonstrated [53,54]. These platforms provide effective means of identifying factors that influence patients’ adherence to AET [55]. A qualitative evidence synthesis further highlighted how informal support, both within online cancer communities and from fellow patients, can help women self-manage side effects and maintain adherence [26].

This underscores the significance of engaging with e-patients [52], who can both generate medical information for one another and comprehend complex information, sharing it effectively [56]. However, seeking information from other patients and forums also carries the risk of misunderstanding the clinical rationale for extending AET, as demonstrated in our study, or coming across inaccurate information about the treatment [57] and how to manage side effects.

Greater attention from HCPs to the role of online forums is warranted as these platforms help identify patients’ needs and concerns [35], including the questions and uncertainties women face when considering extended AET. Our findings suggest that a positive relationship with HCPs, based on trust in clinical advice, effective communication, and ongoing support, can encourage women to accept and continue extended treatment, especially when they are actively involved in decision-making [25]. In the context of treatment extension, tailored communication tools at key stages of the care pathway may facilitate more effective conversations between patients and HCPs about medication and side effects to monitor [25]. This is particularly important for side effects linked with extended AET, including the risks of endometrial cancer, thromboembolic events, and osteoporosis. Patient decision aids have proven to support shared decision-making and improve outcomes in breast cancer treatment, including AET [58-60].

Our study found that decision-making around extended AET may evolve over time, as shown in research on both 5-year [61,62] and 10-year regimens [39]. Concerns about extended AET can arise at any point in the treatment journey, causing uncertainty and reassessment of treatment decisions [57]. It is therefore crucial for clinicians to reengage with shared decision-making principles, using key points along the care pathway to review patients’ views. This would enable a reassessment of whether the potential benefits of extended treatment outweigh side effects by, for example, focusing on absolute rather than relative risk reduction and considering the impact on quality of life during treatment [55]. With the growing number of women undergoing extended AET, greater involvement of GPs and other trained HCPs (gynecologists, psychologists, and physiotherapists), as recommended by health authorities [29,30], and improved coordination between primary care (including pharmacists) and cancer centers could enhance treatment adherence and support comprehensive follow-up throughout the care pathway. It would also help tailor care to women’s personal circumstances and life plans (eg, desire for pregnancy) [63] and may reassure those for whom continuation of AET beyond 5 years is not medically necessary. Finally, it may also help address the emotional ambivalence experienced by some women at the end of extended AET and support a smoother transition out of treatment.

This qualitative netnographic study has several limitations. First, the representativeness of women posting on breast cancer–related discussions is uncertain. Our findings are based on self-reported perceptions shared in an online environment by internet users, which may not fully reflect broader experiences of all women undergoing extended AET. Second, women who use online forums to express negative sentiments, including those related to treatment side effects, could be overrepresented as patients experiencing difficulties may be more likely to seek support in such communities as noted in the literature [64] and by some forum users themselves through their posts. Finally, the analysis was limited to data from 5 online forums, representing a limitation in terms of scope and generalizability of the findings.

Despite the limitations, the diversity of women’s profiles, the richness of the data, and the consistency of emerging themes support the robustness of the results and their relevance for informing recommendations around extended AET. A key strength of this study lies in a use of a variety of online discussion forums, with differing levels of activity and interaction styles. Some women engage in high-traffic, generalist forums where topics may extend beyond breast cancer, while others seem to favor close-knit communities focused on the disease or use these platforms primarily to seek factual medical information. The tone and content of forums range from informal personal narratives and emotional support to more formal, technical discussions, especially on platforms moderated by health care professionals. Posts also vary in length from brief comments to more detailed contributions. Although these differences do not permit definitive conclusions, it is noteworthy that a consistent set of themes was identified across platforms.

Given its netnographic nature and the researcher’s nonparticipant stance, this study does not interfere with forum interactions, thereby preserving spontaneity and authenticity [41]. Such interactions are less susceptible to social desirability bias than those in individual interviews, group discussions, or traditional ethnographic settings. Another key strength lies in longitudinal follow-up of some women across several years and different stages of their care trajectories. This provides insights into how treatment decisions evolve over time, in response to changing personal circumstances, updates in clinical guidelines, and, occasionally, interactions with other peers potentially influencing perspectives. Such dynamics are more challenging to capture through data collection methods where participants typically express themselves within a specific context and at a single point in time.

Our study demonstrates that online forums are a valuable resource for understanding how women navigate extended AET, providing new insights into their proactive information-seeking from both medical and nonexpert sources. Understanding and acceptance of extended therapy were influenced by the timing and manner of information delivery. Decision-making patterns—ranging from acceptance to hesitation or refusal—may evolve throughout the treatment journey. These findings underscore the importance of providing clear, accessible information and personalized communication tools at the prescription and at key stages of the care pathway to support informed choices, foster adherence, and preserve quality of life. With the increasing number of women in long-term treatment pathways, strengthening coordination between primary care and hospital services, including follow-up by trained GPs and other HCPs, in collaboration with cancer centers, may help ensure continuity of care and comprehensive support.

This analysis of online forums will inform a follow-up study aimed at optimizing the communication about extended AET by integrating patients’ and HCPs’ perspectives and exploring the lived experience of long-term treatment.