Abstract
Objective:
To determine the safety of semi-permanent needles alone or combined with filiform needles in patients treated within a pediatric oncology unit during antineoplastic therapy.
Methods:
A retrospective review of electronic medical records at the Pediatric Cancer Center Barcelona of Hospital Sant Joan de Déu, Spain. Data were collected from September 1, 2019, to September 30, 2021, including all oncology patients treated with semi-permanent needles at the integrative pediatric oncology unit. The primary outcome was the safety of acupuncture in pediatric cancer patients, specifically assessing infection and bleeding risks, considering sequential levels of neutropenia and thrombocytopenia.
Results:
A total of 196 patients (59.2% boys, 40.8% girls) underwent acupuncture. The median age at first treatment was 11.82 years (range: 0.2-34.0 years). The median number of treatments per patient was 4 (range: 1-44), totaling 1107 acupuncture sessions. Of these, 370 (33.4%) were performed in patients with neutropenia and 305 (27.6%) in patients with thrombocytopenia. A total of 9360 semi-permanent needles and 5125 filiform needles were used. No cases of sepsis, local infections, or skin irritation were reported within 72 hours post-removal. One self-limited adverse event—a superficial ear hematoma in a patient with grade 4 thrombocytopenia—was observed, which resolved spontaneously without complications.
Conclusion:
Semi-permanent needle therapy, alone or combined with filiform needles, is a safe acupuncture modality when used within pediatric oncology settings, including care contexts that encompass a small number of adolescents and young adults. This study supports the feasibility of incorporating semi-permanent needles into integrative oncology protocols within pediatric oncology practice.
Registration number:
ClinicalTrials.gov (NCT05585463).
Introduction
Acupuncture is a widely recognized complementary treatment modality, endorsed by the World Health Organization (WHO) since 1979 for its efficacy and safety. 1 It involves the insertion of fine, sterile stainless-steel needles at specific points on the body to achieve therapeutic effects through neuromodulation. In recent years, acupuncture has garnered significant attention in the field of oncology, with over 350 publications supporting its use in managing various cancer and cancer therapy related symptoms, including peripheral neuropathy, fatigue, nausea and vomiting, and radiation-induced xerostomia. 2
While the safety and efficacy of acupuncture using filiform needles in adult oncology patients are well established, 3 including during antineoplastic therapy and in those with thrombocytopenia, 4 its application in pediatric oncology presents unique challenges. Concerns about the risk of bleeding and infection, particularly in children with compromised immune function, have historically limited its use. 5 However, preliminary evidence suggests that acupuncture using filiform needles is generally safe for children and adolescents with cancer. It remains unclear whether these initial findings are applicable to other types of acupuncture needles, techniques, or needle depth. 6 Furthermore, alternative acupuncture techniques, such as semi-permanent needles, have not been extensively studied in children, especially in the context of cancer. 7
Semi-permanent needles (also referred to as embedding needles in some literature) offer a visually discreet and potentially less intimidating option for pediatric patients. These needles, with a shorter length and adhesive backing, are designed to remain in place for several days, providing sustained therapeutic benefit while minimizing discomfort. 8 They are particularly suited for children who may be apprehensive with traditional needle insertion. In addition, semi-permanent needles can be strategically placed in covered areas of the body, which may prevent young children from seeing or tampering with the needles. These features may improve adherence and symptom management for children who might otherwise refuse repeated needle insertions. Despite these potential advantages, the safety profile of semi-permanent needles has not been comprehensively studied, particularly in the context of pediatric oncology, where patients often have unique vulnerabilities and treatment-related risks. Importantly, real-world pediatric oncology practice often includes adolescents and young adults (AYA) treated within pediatric units. Therefore, studies conducted in these settings, such as ours, naturally reflect this broader population, while the majority of patients remain within the traditional pediatric age range. This study aims to address this critical gap in the literature.
Current literature primarily focuses on the safety of filiform acupuncture needles, with limited studies examining the safety of semi-permanent needles in pediatric populations.9,10 Studies investigating the use of semi-permanent needles in non-oncological settings have not reported significant adverse effects, suggesting that this technique may have a favorable safety profile.11,12 The absence of data specific to pediatric oncology highlights a critical need for further investigation.
This retrospective study aims to address this knowledge gap by evaluating the safety of semi-permanent needles in patients treated within a pediatric oncology unit, including a small number of adolescents and young adults. By assessing adverse events such as infection and bleeding, this study seeks to provide evidence-based guidance on the use of semi-permanent needles as a safe and effective adjunctive therapy in pediatric oncology settings.
Material and Methods
The study was approved by the Ethics Committee of Hospital Sant Joan de Déu (ACUSAFE2021 PS-14-22) and was registered at ClinicalTrials.gov (NCT05585463). In accordance with reporting guidelines, we followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. 13
Design
This was a 2 year, retrospective, single-center study conducted at the Integrative Pediatric Oncology Unit, Hospital Sant Joan de Déu, Barcelona, Spain, from September 1, 2019, to September 30, 2021.
Sample and Participants
All patients receiving antineoplastic therapy who visited the Integrative Pediatric Oncology Unit during the study period were consecutively included, without any sampling technique. This cohort primarily comprised pediatric patients but also included adolescents and young adults who are routinely managed within pediatric oncology services at our institution. Patients were eligible if they had received at least one acupuncture treatment involving semi-permanent needles. Participants could have also received other acupuncture modalities, such as filiform needles.
Exposure
A pediatrician with over 10 years of experience in both pediatric and adult acupuncture administered acupuncture treatments with semi-permanent needles following strict hygienic protocols (skin disinfection with 70% alcohol and the use of gloves). The semi-permanent needles used were Pyonex® needles, individually packaged in specially designed plastic cases that ensure aseptic insertion without direct contact with the needle or adhesive. The hypoallergenic, latex-free adhesive helped minimize the risk of skin irritation. The needles used measured 0.11 mm (diameter) × 0.3 mm (length), 0.15 mm × 0.6 mm, and 0.17 mm × 0.9 mm. The shorter needles (0.3 and 0.6 mm) were specifically selected for auricular acupuncture (Figure 1). Needle selection was individualized based on the patient’s age and skin sensitivity, with shorter needles used for children under 2 years of age or for those with increased skin sensitivity, regardless of age. Needle insertion avoided irritated skin, open wounds, primary tumor sites, and edematous areas. In children under 3 years of age, needles were inserted in covered body areas to prevent the child from seeing or tampering with them. Semi-permanent needles were removed before patients entered the post-chemotherapy aplasia period. As a precaution, semi-permanent needles were inserted only if the patient’s total neutrophil count was equal to or greater than 1000/μL on the day of placement, in accordance with institutional safety protocols. However, retrospective review revealed that in some cases, patients’ ANC values later decreased below this threshold while the needles remained in place, reflecting expected hematologic variability during chemotherapy cycles rather than protocol deviation.

Semi-permanent acupuncture needle used in pediatric oncology patients.
In some cases, semi-permanent needles were combined with filiform needle acupuncture or electroacupuncture. This decision was determined by the acupuncturist based on several factors. These included the patient’s age, whether auriculotherapy was included in the treatment, and the patient’s willingness to accept filiform needle insertion. Electroacupuncture is the preferred treatment for pain management in oncology patients when feasible. It offers effective pain relief but requires the use of filiform needles and the patient to remain still for 20 to 30 minutes. Typically, it is offered to patients over 6 years old, when appropriate. This individualized approach allowed the acupuncturist to tailor the treatment based on the patient’s specific needs and preferences
For the filiform needle acupuncture, Japanese J-type Seirin® needles were employed. These needles, crafted from surgical steel, feature a cannula that prevents direct contact with the needle, ensuring sterility and facilitating smooth, painless insertion. The depth of needle insertion varied between 3 mm and 1 cm, depending on the treatment area. Needle sizes included 0.10 mm × 15 mm, 0.12 mm × 15 mm, 0.14 mm × 15 mm, and 0.16 mm × 15 mm. No active manipulation of the needles was performed during the procedure.
Electroacupuncture was introduced during the last 6 months of the study and was performed using the ITO ES-160 Ryodoraku 6-channel stimulator. This modality was used as a second-line treatment for managing oncological pain, neuropathic pain, nausea, vomiting, constipation, diarrhea, headache, abdominal pain, pruritus, and hot flashes, in patients with refractory symptoms or partial response to filiform needle acupuncture or semi-permanent needles. To ensure safety, the electro stimulator and its accessories (cables and clamps) were thoroughly cleaned with a disinfection solution after each use. For patients with viral or bacterial infections requiring electroacupuncture, the device was covered with a non-breathable material and thoroughly cleaned after every session. Electroacupuncture was utilized only in children aged 6 years and older.
Outcomes and Data Collection
Data was extracted retrospectively by 3 researchers (CLSR, MBNA, EMG) from the electronic medical records using a standardized data extraction form created with Microsoft Excel. The collected data was pseudo-anonymized to maintain participants’ confidentiality. The following variables were extracted:
Sociodemographic data: age, sex, race, country of origin, hospital treatment area, cancer diagnosis, oncological treatment, neutrophil count, and platelet count. Neutropenia and thrombocytopenia were classified according to the Common Terminology Criteria for Adverse Events (CTCAE) Version 5.0. 14 Neutrophil and platelet counts were measured on the same day, prior to the application of acupuncture treatment. CTCAE classification was used to describe the hematologic status of patients at baseline, allowing the distribution of acupuncture sessions to be analyzed across different levels of neutropenia and thrombocytopenia.
Treatment characteristics: Number of sessions (using only semi-permanent needles or using combination with filiform), number of semi-permanent and filiform needles used, needle placement location (body, ear or combination), needle removal setting, and needle retention duration.
Adverse events: The primary safety outcome was sepsis episodes, defined as a positive blood culture for Gram-positive bacteria within 72 hours after needle removal. Secondary outcomes included local infection, bleeding and other local skin irritations, as reported in the medical record. Because this retrospective study relied on routinely documented clinical records, adverse events were recorded as described in the charts and were not prospectively graded using CTCAE criteria. Outcomes were also analyzed according to the severity of neutropenia and thrombocytopenia.
Statistical Analysis
Qualitative variables such as sex, race, cancer diagnosis, and the use of additional acupuncture modalities were summarized using absolute frequencies and percentages. Quantitative variables, including age, number of acupuncture sessions, the number of semi-permanent and filiform needles used, and duration of needle retention, were described using the median, minimum and maximum, as they followed a non-normal distribution.
The number of adverse events (sepsis, local infections, bleeding and skin irritation episodes) was stratified according to the severity of neutropenia and thrombocytopenia based on the Common Terminology Criteria for Adverse Events (CTCAE) Version 5.0, to ensure that all patient subgroups were represented and described. Given the small occurrence of adverse events, no comparative statistical tests were performed to evaluate the relationship between neutropenia or thrombocytopenia severity and the incidence of these events. Instead, the results focused on describing the safety profile of acupuncture treatment in this cohort.
All analyses were conducted using R software, version 4.4.1. 15 No imputation of missing data was necessary.
Results
Participants
A total of 196 cancer patients receiving antineoplastic regimens treated with semi-permanent needles were included in the study. The median age of participants was 11.8 years (range: 0.2-34.0 years), with 116 boys (59.2%) and 80 girls (40.8%). The most common cancer diagnoses among participants included extracranial solid tumors (n = 101), CNS tumors (n = 48), lymphoma (n = 27), and leukemia (n = 20). A detailed breakdown of the demographic and clinical characteristics is provided in Table 1.
Demographic Characteristics of the Participants.
Other tumors: calvarial histiocytosis, pancreatic myofibroblastic tumor, peritoneal mesothelioma.
Acupuncture Treatments Description
A total of 9360 semi-permanent needles and 5125 filiform needles were applied over 1107 sessions. The median number of needles used per session was 7, with a range spanning from 1 to 25 needles. Exclusive use of semi-permanent needles was recorded in 749 sessions (67.7%), while a combination of semi-permanent and filiform needles was employed in 358 sessions (32.3%). Body insertion was performed in 668 sessions (60.3%), auricular acupuncture in 23 sessions (2.1%), and a combination of body and auricular insertions in 416 sessions (37.6%).
Of the total 1107 acupuncture sessions, 86.4% of these were conducted during active cancer treatment and 13.6% during follow-up. Of the active treatment sessions, most occurred during chemotherapy (54.8%), followed by combined treatments (11.4%) and immunotherapy (2.0%).
Most of the acupuncture sessions were conducted in inpatient settings (54.8%), followed by hospital outpatient consultations (29.6%), day treatment room (13.9%), procedure areas (0.3%), the bone marrow transplantation unit (1.1%), and the intensive care unit (0.3%; Table 2).
Description of the Acupuncture Treatments.
Acupuncture Treatment According to Neutropenia and Thrombocytopenia
The number of acupuncture sessions and the type of needles used were further analyzed according to the degree of neutropenia and thrombocytopenia (Tables 3 and 4). Regarding neutropenia, 737 sessions (66.6%) were performed in patients with normal neutrophil counts, 161 sessions (14.5%) in patients with grade 1 neutropenia, 137 sessions (12.4%) in grade 2, 59 sessions (5.3%) in grade 3, and 13 sessions (1.2%) in grade 4 neutropenia. Similarly, 882 sessions (72.4%) were carried out in patients with normal platelet counts, 299 sessions (18.0%) in grade 1 thrombocytopenia, 31 sessions (2.8%) in grade 2, 57 sessions (4.2%) in grade 3, and 28 sessions (2.5%) in grade 4 thrombocytopenia.
Number of Sessions and Needles Inserted According to the Degree of Neutropenia.
Normal (≥2000/μL), Grade 1 (1500-2000/μL), Grade 2 (1000-1500/μL), Grade 3 (500-1000/μL), Grade 4 (<500/μL).
Number of Sessions and Needles Inserted According to the Degree of Thrombocytopenia.
Normal (≥150 000/μL), Grade 1 (75 000-150 000/μL), Grade 2 (50 000-75 000/μL), Grade 3 (25 000-50 000/μL), Grade 4 (<25 000/μL),
Semi-permanent needles were left in place for a median of 4 days (range: 1-4). Regarding needle removal, 47.8% of the needles were removed in the hospital, while 52.2% were removed at home.
Adverse Events
Out of 1107 acupuncture sessions, no cases of sepsis, local infection, or skin irritation were reported across all degrees of neutropenia (Table 5). Similarly, no bleeding events occurred in patients with normal platelet counts or mild to moderate thrombocytopenia (Grades 1-3). The only adverse event documented during the observation period was a small superficial auricular hematoma in 1 pediatric patient with grade 4 thrombocytopenia. The event was self-limited and resolved spontaneously without intervention, consistent with a mild bleeding event (CTCAE grade 1) and representing a rate of 3.57 events per 100 treatments in this subgroup (Table 6). No adverse events were recorded among adolescent or young adult patients.
Sepsis, Local Infection, and Skin Irritation Events Stratified by Patients’ Baseline Neutropenia Grade (CTCAE).
Normal (≥2000/μL), Grade 1 (1500-2000/μL), Grade 2 (1000-1500/μL), Grade 3 (500-1000/μL), Grade 4 (<500/μL); CTCAE grading refers to the patients’ neutropenia status at the time of acupuncture treatment, not to the severity of the adverse events.
Bleeding and Skin Irritation Events by Baseline Thrombocytopenia Grade of the Patient (CTCAE).
Normal (≥150 000/μL), Grade 1 (75 000-150 000/μL), Grade 2 (50 000-75 000/μL), Grade 3 (25 000-50 000/μL), Grade 4 (<25 000/μL); CTCAE grading refers to the patients’ thrombocytopenia status at the time of acupuncture treatment, not to the severity of the bleeding events.
Discussion
This study is the first to evaluate the safety of semi-permanent needles, both alone and in combination with filiform needles, in patients treated within a pediatric oncology unit during antineoplastic therapy. Over a 2-year period, 196 cancer patients underwent 1107 acupuncture sessions involving 9360 semi-permanent needles and 5125 filiform needles. Notably, no serious adverse events related to infection or bleeding were observed. The only adverse event documented was a superficial auricular hematoma, which was self-limited and resolved spontaneously without intervention. Based on its clinical characteristics, the event would correspond to a mild bleeding event (CTCAE grade 1), supporting the favorable safety profile of the technique even in patients with severe thrombocytopenia. Although a small number of adolescents and young adults were included, the cohort was overwhelmingly pediatric, with more than 95% of patients under 20 years of age, and the sole adverse event occurred in a pediatric patient.
The absence of significant complications in this study can likely be attributed to several key factors, including adherence to safety protocols, the use of sterile, high-quality materials, and the experience of the trained practitioner providing acupuncture within a pediatric oncology framework. First, all treatments were administered by an experienced pediatrician with over a decade of practice in both pediatric and adult acupuncture, with an average of 2500 acupuncture treatments per year. The acupuncturist’s expertise, combined with the meticulous use of high-quality needles, ensured precise and hygienic needle insertion. The semi-permanent needles’ adhesive design, along with the insertion cannula for the filiform needles, likely contributed to maintaining aseptic conditions throughout the procedures.
Another crucial aspect that likely minimized the risk of complications was the use of standardized acupuncture protocols based on current recommendations for safety practice, 16 particularly during chemotherapy cycles. These protocols involved a thorough review of patients’ laboratory results, with special attention given to neutropenia and thrombocytopenia levels. In cases where patients were entering post-chemotherapy aplasia, semi-permanent needles were removed to mitigate the risk of infection during periods of heightened vulnerability. For patients with grade 4 neutropenia, semi-permanent needles were inserted only if the patient was on antibiotic coverage, and these needles were removed within 24 hours to further minimize risk.
The vast majority of patients in this cohort were children and adolescents, with a median age of 11.8 years (range 0.2-34 years), reflecting real-world practice within pediatric oncology units, where a limited number of adolescents and young adults may continue to receive care. Importantly, no adverse events were observed among adolescent or young adult patients, and the only documented adverse event—a superficial auricular hematoma—occurred in a pediatric patient, indicating that inclusion of older patients did not influence the observed safety profile.
Currently, literature on the safety of semi-permanent needles in pediatric oncology is limited. In a recent systematic review, 7 we identified only 2 studies that explored this technique in children undergoing chemotherapy17,18(p. 2). Both studies aimed to evaluate the efficacy of semi-permanent needles in reducing chemotherapy-induced nausea. However, these studies have several limitations: their focus was on efficacy rather than safety, and adverse events such as bleeding, infection, or hematoma were not systematically assessed or reported. Therefore, the absence of adverse events in these reports should not be interpreted as evidence of confirmed safety. Also, the protocols employed differed significantly from ours; Bai et al 17 utilized a protocol with a needle retention time of only 1 minute, whereas our study involved retention times of several days. This difference in protocol could impact the safety profile and tolerability of the technique. Lastly, the sample sizes in these studies were smaller compared to ours, with 74 and 60 patients respectively, whereas our study included 196 pediatric cancer patients across 1107 acupuncture sessions, using 9360 semi-permanent needles.
This study has several limitations. First, its single-center design limits the generalizability of the findings to other institutions, professionals, and patient populations. The study reflects the specific practices of the Integrative Pediatric Oncology Unit (details omitted to preserve anonymity), which may differ from protocols, materials, and practitioner expertise at other centers, making direct comparisons challenging.
Second, the primary safety outcome was sepsis episodes, defined as a positive blood culture for Gram-positive bacteria within 72 hours after needle removal. However, not all infections may present with a positive blood culture, which complicates the interpretation of safety data related to sepsis.
Finally, the retrospective nature of the study restricts the assessment to pre-registered outcomes, such as infection and bleeding events. As a result, less severe adverse events that were not systematically recorded or anticipated may not have been evaluated. While the study provides important data on major adverse events, it does not capture the full spectrum of potential minor complications or side effects that could arise from semi-permanent needle use in a pediatric oncology setting.
Conclusions
This study provides the first comprehensive evaluation of the safety of semi-permanent needles, both alone and in combination with filiform needles, in a pediatric oncology unit. The findings indicate that semi-permanent needles are a safe and well-tolerated adjunctive therapy for symptom management in pediatric oncology practice, including care settings that encompass a small number of adolescents and young adults. Over the course of 1107 acupuncture sessions, involving the use of 9360 semi-permanent needles and 5125 filiform needles, no serious adverse events were observed. Specifically, there were no cases of sepsis, local infection, or skin irritation reported during the study period.
A single, self-limited bleeding event was documented: a superficial ear hematoma occurred in 1 patient with grade 4 thrombocytopenia and resolved spontaneously without complication. Importantly, no significant bleeding events or other safety concerns were observed, underscoring the tolerability of this intervention even in a particularly vulnerable population.
While these findings highlight the safety of semi-permanent needles as an adjunctive therapy for symptom management in pediatric oncology settings, the retrospective design and single-center nature of the study limit the generalizability of the results. Future research should address these limitations by conducting multi-center, prospective studies that evaluate a broader range of outcomes. Such studies will be critical to furthering our understanding of the safety profile and therapeutic potential of semi-permanent needles in integrative pediatric oncology care.
Footnotes
Acknowledgements
The authors extend their heartfelt gratitude to the patients and their families who have participated in the Integrative Pediatric Oncology Unit at the Pediatric Cancer Center Barcelona, Hospital Sant Joan de Déu. We are deeply grateful to the multidisciplinary team at Hospital Sant Joan de Déu, whose dedication and expertise have been vital in delivering integrative care.
Special thanks to “Obra Social SJD-fundraising”, whose unwavering and substantial support has been foundational for the establishment and continued operation of the Integrative Pediatric Oncology Unit. We also recognize the invaluable contributions of the hospital management, administrative teams, and clinical colleagues, whose collaborative efforts have been instrumental in implementing this innovative model of supportive care in pediatric oncology
Author’s Note
Sara Perez-Jaume is now affiliated with Biostatistics Unit, Department of Basic Clinical Practice, Universitat de Barcelona (UB), Barcelona, Spain.
ORCID iDs
Ethical Considerations
The study was approved by the Ethics Committee of Hospital Sant Joan de Déu (ACUSAFE2021 PS-14-22).
Consent to Participate
This observational study was deemed to involve minimal or no risk to participants, and as such, the ethics committee at Hospital Sant Joan de Déu (ACUSAFE2021 PS-14-22) approved a waiver of informed consent. The approval was granted due to several key considerations: (1) the study’s retrospective design, covering an extended timeframe, rendered it unfeasible to obtain consent from all individuals involved; (2) requiring individual consent would have compromised the feasibility of the research; (3) anonymizing the data was not a viable option for conducting the analysis; and (4) strict measures were taken to maintain the confidentiality of all personal information throughout the study.
Author Contributions
Conceptualization, EMG, CLSR and BNA; methodology, IJ, CF-J and OCM; statistical analysis, SPJ; investigation, EMG, BNA, CLSR and AMLM; writing—original draft preparation, EMG, BNA and CF-J; writing—review and editing, CF-J, SPF, IJ, AMLM and OCM; supervision, IJ, OCM and AMLM. All authors have read and agreed to the published version of the manuscript.
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was partially funded by a research grant from Societat Científica d’Acupuntura de Catalunya i Balears (SCACB).
The Integrative Pediatric Oncology Unit (UOPI) at the Pediatric Cancer Center Barcelona was made possible through substantial support from Xocolatada Solidària, our primary source of funding. We also acknowledge generous contributions from corporate donors, including VERITAS, TE Connectivity, COFIDIS, KPMG, Informatica Medico Farmaceutica SL, Planeta Corporación, CaixaBank, and DocSave. These contributions, along with those of countless community associations and solidarity initiatives, including “Una pizca de magia,” Asociación Pulseras Candela, Fundación Inocente Inocente, and Fundación Xana have played an essential role in sustaining the unit and advancing our integrative approach to pediatric oncology care.
Declaration of Conflicting Interest
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
