Shared Decision Making in Oncology and Its Implementation in Cervical Cancer Management in the Philippines: A Narrative Review.

PURPOSE: Shared decision making (SDM) is an approach where clinicians and patients make decisions together using the best available evidence. Although much studied, recognized to be ethically imperative, and recommended in international health policies, it remains poorly implemented. In the Philippines, there are limited studies on patient decision making preferences and SDM. Practical guidance on the implementation of SDM or use of patient decision aids (PtDAs) is often not detailed in existing national clinical practice guidelines in oncology. METHODS: We performed a systematic search of Philippine literature on SDM in oncology and an iterative review of international literature on the philosophy and methods of SDM, the utility and effectiveness of PtDAs, and the facilitators and barriers to implementation or usage. We contextualized our review to the cervical cancer management and health service delivery in the Philippines. RESULTS: Local literature is limited to five scientific publications and two registered studies. International literature encompasses patient decisional preferences, the role of PtDAs and the standards for their development and evaluation, their effectiveness, and barriers and facilitators to their use in cancer-related decision making. We discussed the implications on the management of cervical cancer in the Philippines, challenges in health service delivery and standards, and SDM research. CONCLUSION: Local SDM research is limited. Our preliminary experience in a multicenter clinical trial in Manila on PtDA use in the framework of SDM in cervical cancer suggest good patient and clinician acceptability. Challenges to implementation such as unfavorable financial situations, urgency of clinical decisions, low patient or caregiver educational attainment, and poor integration of multidisciplinary and SDM in organizational workflows will be important when implementing SDM in different settings.

Patient Decision Aid for Chemotherapy or Exclusion in Cisplatin-Intolerant Patients With Locally Advanced Cervical Cancer: Development, Alpha Testing, and Peer Validation.

PURPOSE: In locally advanced cervical cancer (LACC), adding cisplatin to radiotherapy (RT) improves survival but increases toxicity. Among patients with cisplatin contraindications, RT compliance may be compromised by toxicity because of cisplatin or a substitute. In shared decision making, a patient decision aid (PtDA) may decrease decisional conflict and attitudinal barriers, thereby improving treatment compliance. METHODS: Following International Patient Decision Aid Standards (IPDAS) guidelines, a steering committee of two radiation oncologists, a gynecologic oncologist, an oncology nurse, a clinical psychologist, a cancer survivor, and a caregiver developed the chemotherapy or exclusion in cisplatin-intolerant patients with LACC (CECIL) prototype, a PtDA for cisplatin-intolerant patients with LACC deciding about adding chemotherapy to RT. The prototype was alpha-tested using the e-Delphi method. The patient decision aid research group Ottawa Acceptability Questionnaire was used to evaluate comprehensibility, length, amount of information, neutrality, and overall suitability for decision making. The prototype was then independently evaluated by local internal, local external, and international reviewers using the IPDAS checklist version 4, which encompasses information, probabilities, values, guidance, development, evidence, disclosure, plain language, and evaluation. RESULTS: Alpha testing showed high practitioner acceptability (all items with mean and median scores ≥4; overall mean score 4.70 of 5.00) and good patient acceptability (all items rated good to excellent). Content validation showed that the PtDA satisfied all IPDAS six qualifying and six certification criteria, with high overall mean score (3.63 of 4.00) for all 17 applicable quality criteria. CONCLUSION: The CECIL prototype shows good practitioner and patient acceptability, and content validity on peer review. Clinical testing to determine its effectiveness in reducing decisional conflict is ongoing.

Antibody response to enterotoxigenic Bacteroides fragilis of Filipino colorectal cancer patients.

Background: Several species of the gut microbiota have been implicated in colorectal cancer (CRC) development. The anaerobic bacterium enterotoxigenic Bacteroides fragilis (ETBF), has been identified to produce fragilysin, a toxin known to cleave E-cadherin, thereby leading to carcinogenesis. Objective: To determine the antibody response of CRC patients against ETBF to ascertain whether significant difference exists or whether antibody response is related to tumor grade and tumor stage. Methods: Informed consent was obtained from histologically confirmed CRC casesand their age- and sex-matched clinically healthy controls. Plasma samples from the participants were subjected to in-house enzyme-linked immunosorbent assay (ELISA) to determine their antibody levels. Results: Using ETBF total protein as coating antigen, 38/39 (97%) CRC cases and 36/39 (92%) controls showed anti-ETBF IgG above cut-off, while all (100%) CRC cases and 36/39 (92%) controls had anti-ETBF IgA levels above cut-off. With culture broth as coating antigen, all (100%) CRC cases and 37/39 (95%) controls had anti-ETBF IgG levels above cut-off. For anti-ETBF IgA, all (100%) cases and controls had levels above cut-off. Statistical analysis reveals no significant difference (P > 0.05) on the number of CRC cases and controls with IgG and IgA antibody levels above cut-off value. Also, there's no significant difference (P > 0.05) in the mean anti-ETBF antibody levels of cases who were at different tumor grade (well differentiated and moderately and poorly differentiated) and tumor stage (early and advanced). Conclusions: These results suggest that Filipino CRC cases and their clinically healthy matched controls exhibit antibody responses against ETBF.

Clinical outcomes of single application multi-fractionated CT-guided interstitial high-dose-rate brachytherapy for locally advanced cervical cancer: A multi-institution initial experience.

Purpose: The aim of the study was to evaluate the safety and clinical outcomes of single application multi-fractionated computed tomography (CT)-guided interstitial high-dose-rate brachytherapy given in four fractions in locally advanced cervical cancer. Material and methods: Patients with locally advanced cervical cancer stage IIB-IVA treated definitively with external radiation ± weekly cisplatin, followed by single application multi-fractionated CT-guided interstitial high-dose-rate brachytherapy in four fractions were included. Dosimetry data, clinical response, and toxicity records were reviewed. Results: Between January 2018 and December 2022, twenty-two patients were included. Clinical stage distribution was as follows: IIB - 13.6%, IIIB - 27.3%, IIIC - 22.7%, and IVA - 36.4%. Mean high-risk clinical target volume (HR-CTV) was 66.19 ±32.69 cm3, and HR-CTV D90 dose was 86.8 ±1.7 Gy. 2 cc doses to bladder, rectum, and sigmoid were 84.6 ±2.8 Gy, 71.5 ±2.4 Gy, and 65.6 ±4.0 Gy, respectively. Mean overall treatment time was 66 ±21 days. With a median follow-up of 11.5 months (range, 5-44 months), median survival and local control were not achieved. One-year local control rate, one-year progression-free survival, and one-year overall survival were 82%, 66%, and 78%, respectively. Univariate analysis showed overall treatment time to be the only variable associated with all oncologic outcomes. For acute toxicity, grade 3 toxicity in four patients and grade 4 toxicity of infection in one patient were observed. For late toxicity, grade 3 gastrointestinal toxicity was noted in two patients. Conclusions: Initial results suggest that single application multi-fractionated CT-guided interstitial brachytherapy given in four fractions in locally advanced cervical cancer seems to be feasible and safe, but additional evidence is needed to generate more validated conclusions.

Orbital mold brachytherapy for recurrent orbital mesenchymal chondrosarcoma: a case report.

PURPOSE: The aim of this case report is to present a case of orbital mesenchymal chondrosarcoma sarcoma with multiple recurrences, and to report technical details of a contemporary approach for orbital brachytherapy that can be used in low-resource settings. MATERIAL AND METHODS: A 46-year-old female diagnosed with recurrent orbital mesenchymal chondrosarcoma of the left orbit presented with her third local recurrence. The patient proceeded with conservative surgery with planned adjuvant high-dose-rate brachytherapy 2 weeks post-surgery. Brachytherapy mold applicator was fabricated using thermoplastic mask, ProGuide catheter needles, catheter fixation buttons, and a strip of gauze. Ideal catheter placement was done with CT simulation planning. RESULTS: High-risk clinical target volume (HR-CTV) corresponded to gross tumor residual, and intermediate-risk clinical target volume (IR-CTV) corresponded to the whole orbit. Flexitron iridium-192 high-dose-rate (HDR) brachytherapy plan was generated using Oncentra brachytherapy planning system. The treatment plan had HR-CTV total dose of 55.6 Gy and equivalent dose in 2 Gray fractions (EQD2) of 96 Gy. IR-CTV total dose was 45.5 Gy and EQD2 of 70 Gy. The plan was evaluated using dose-volume histogram and dosimetric parameters, which showed adequate irradiation of tumor volume and at-risk areas. The patient underwent orbital brachytherapy without any adverse events, except for mild skin erythema. One-year post-treatment showed no local recurrence and no soft tissue necrosis or swelling. CONCLUSIONS: In the previously irradiated orbital sarcoma patient, adjuvant brachytherapy is an effective and safe modality for the delivery of sufficient radiation dose to the target, as presented in the current case report. The materials used in the brachytherapy applicator are easily available in majority of radiation therapy centers and can be manufactured even in low-resource settings.

Clostridioides difficile antibody response of colorectal cancer patients versus clinically healthy individuals.

Dysbiosis, defined as an imbalance in the gut microbiota caused by too few beneficial bacteria and an overgrowth of bad bacteria, yeast, and/or parasites, is now being associated with several diseases, including the development of colorectal carcinoma (CRC). In this study, the potential association of Clostridioides difficile (formerly Clostridium difficile) with CRC was investigated. Plasma samples obtained from preoperative histologically confirmed CRC patients (n=39) and their age- and sex-matched clinically healthy controls (n=39) were analyzed for antibodies to toxin B of C. difficile (anti-tcdB) by enzyme-linked immunosorbent assay (ELISA). A significantly greater number (p=0.012) of CRC cases (n=26/39, 66.7%) had anti-tcdB IgG levels above the cutoff value compared with controls (n=12/39, 30.8%). Eight cases (8/39, 20.5%) and none of the controls registered anti-tcdB IgA levels above the cutoff value (p=0.0039). Anti-tcdB IgG and IgA levels were not shown to be significantly associated with tumor grade or tumor stage. Anti-tcdB IgG showed 66.7% sensitivity and 69.2% specificity. For anti-tcdB IgA, sensitivity and specificity were 20.5% and 100%, respectively. The positive predictive values for anti-tcdB IgA and IgG were 100% and 68.4%, respectively. The anti-tcdB IgA and IgG negative predictive values were 55.7% and 67.5%, respectively. The results suggest the potential association of C. difficile with CRC and anti-tcdB levels, particularly the IgA level. Hence, anti-tcdB antibodies can be candidate serologic markers for CRC.