Radiotherapy resources in the Philippines: A 2022 update.

BACKGROUND: Cancer is the third leading cause of death in the Philippines. Radiotherapy (RT) is integral to the treatment and palliation of cancer. Therefore, RT resources across the country must be surveyed and optimized. METHODS: Online surveys were sent to the heads of all 50 RT facilities in the Philippines. The survey included items regarding the facility itself, personnel, and available services. FINDINGS: The survey had a 98% response rate. 76% of RT facilities in the Philippines are privately owned; 12 are government/public institutions and 8 are academic centers. Over a third are in the National Capital Region; three regions are without a single RT facility. For a population of >110 million, the Philippines has 53 linear accelerators, 125 radiation oncologists, 56 residents, 114 medical physicists, 113 radiation oncology nurses, and 343 radiation therapists. Nine radiation oncology residency programs are active. All facilities are capable of 3D conformal radiotherapy, and 96% are capable of intensity modulated radiotherapy. <30% offer stereotactic radiotherapy, and <50% offer HDR brachytherapy. CONCLUSION: While there has been significant expansion of RT resources over the years, RT remains inaccessible for many in the Philippines. Urgent investment in training and retaining RT personnel is needed as well. Policy summary: With its current cancer burden, the Philippines needs at least 170 linear accelerators, 300 radiation oncologists, and 150 medical physicists. Public/government cancer centers must be built, with priority given to regions without RT facilities. HDR brachytherapy and stereotactic radiotherapy services must also be expanded. A national RT task force must be created to ensure the quality, availability, and accessibility of RT in the Philippines. Further work exploring payment schemes that improve access to RT and mitigate financial toxicity is needed, as well as integration of radiation oncology providers and health policy experts into national health system decision making.

Unplanned Excision of Soft Tissue Sarcomas of the Extremities in a Low-to-Middle-Income Country.

BACKGROUND: Outcomes of unplanned excisions of extremity soft tissue sarcomas (STSE) range from poor to even superior compared with planned excisions in developed countries. However, little is known regarding outcomes in low-to-middle-income countries. This study aimed to determine whether definitively treated STSE patients with a previous unplanned excision have poorer oncologic outcomes compared with those with planned excisions. PATIENTS AND METHODS: Using the database of a single sarcoma practice, we reviewed 148 patients with STSE managed with definitive surgery-78 with previous unplanned excisions (UE) and 70 with planned excisions (PE). RESULTS: Median follow-up was 4.4 years. UE patients had more surgeries overall and plastic reconstructions (P < 0.001). On multivariate analysis, overall survival (OS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) were not worse among UE patients compared with PE patients. Negative predictors for LRFS were high tumor grade (P = 0.031) and an R1 surgical margin (P < 0.001). High grade (P <0.001), local recurrence (P = 0.001), and planned excisions (P = 0.009) predicted poorer DMFS, while age over 65 years (P = 0.011) and distant metastasis predicted poorer OS (P < 0.001). CONCLUSIONS: We recommend systematic re-excision for patients with unplanned excisions. Our study shows that STSE patients with UE, when subjected to re-excision with appropriate surgical margins, can achieve oncologic results similar to those for PE patients. However, there is an associated increased number of surgeries and plastic reconstruction for UE patients. This underscores the need, especially in a resource-limited setting, for education and collaborative policies to raise awareness about STSE among patients and physicians.

Geographic Distribution of Cancer Care Providers in the Philippines.

PURPOSE: In the Philippines, a lower middle-income country in Southeast Asia, 6 of 10 Filipinos die without seeing a doctor. To ensure universal access to cancer care, providers must be equitably distributed. Therefore, we evaluated the distribution of oncologists across all 17 regions in the Philippines. METHODS: We gathered data from the official websites of national medical societies on their members' regional area of practice: Philippine Society of Medical Oncology, Philippine Radiation Oncology Society, Surgical Oncology Society of the Philippines, Society of Gynecologic Oncologists of the Philippines, and Philippine Society of Hospice and Palliative Medicine. We compared this with the regional census to determine the number of board-certified oncologists per 100,000 Filipinos. RESULTS: For a population of almost 110 million, the Philippines has a total of 348 medical oncologists, 164 surgical oncologists, 99 radiation oncologists, 142 gynecologic oncologists, and 35 hospice and palliative medicine (HPM) specialists. This translates to 0.32 medical oncologists, 0.15 surgical oncologists, 0.09 radiation oncologists, 0.13 gynecologic oncologists, and 0.03 HPM specialists for every 100,000 Filipinos. The number of oncologists is highest in the National Capital Region in Luzon and lowest in the Bangsamoro Autonomous Region in Muslim Mindanao. All regions have at least one medical and gynecologic oncologist. Two regions (12%) have no surgical oncologists, five regions (29%) have no radiation oncologists, and eight regions (47%) have no HPM specialists. CONCLUSION: Efforts are needed to increase the number of oncologists and improve equity in their distribution to ensure universal access to cancer care in the Philippines.

Automatic segmentation of nasopharyngeal carcinoma on CT images using efficient UNet-2.5D ensemble with semi-supervised pretext task pretraining.

Nasopharyngeal carcinoma (NPC) is primarily treated with radiation therapy. Accurate delineation of target volumes and organs at risk is important. However, manual delineation is time-consuming, variable, and subjective depending on the experience of the radiation oncologist. This work explores the use of deep learning methods to automate the segmentation of NPC primary gross tumor volume (GTVp) in planning computer tomography (CT) images. A total of sixty-three (63) patients diagnosed with NPC were included in this study. Although a number of studies applied have shown the effectiveness of deep learning methods in medical imaging, their high performance has mainly been due to the wide availability of data. In contrast, the data for NPC is scarce and inaccessible. To tackle this problem, we propose two sequential approaches. First we propose a much simpler architecture which follows the UNet design but using 2D convolutional network for 3D segmentation. We find that this specific architecture is much more effective in the segmentation of GTV in NPC. We highlight its efficacy over other more popular and modern architecture by achieving significantly higher performance. Moreover to further improve performance, we trained the model using multi-scale dataset to create an ensemble of models. However, the performance of the model is ultimately dependent on the availability of labelled data. Hence building on top of this proposed architecture, we employ the use of semi-supervised learning by proposing the use of a combined pre-text tasks. Specifically we use the combination of 3D rotation and 3D relative-patch location pre-texts tasks to pretrain the feature extractor. We use an additional 50 CT images of healthy patients which have no annotation or labels. By semi-supervised pretraining the feature extractor can be frozen after pretraining which essentially makes it much more efficient in terms of the number of parameters since only the decoder is trained. Finally it is not only efficient in terms of parameters but also data, which is shown when the pretrained model with only portion of the labelled training data was able to achieve very close performance to the model trained with the full labelled data.

Predictors of mortality among inpatients with COVID-19 infection in a tertiary referral center in the Philippines.

Objectives: The aim of this study was to determine the predictors of mortality and describe laboratory trends among adults with confirmed COVID-19. Methods: The medical records of adult patients admitted to a referral hospital with COVID-19 were retrospectively reviewed. Demographic and clinical characteristics, and laboratory parameters, were compared between survivors and non-survivors. Predictors of mortality were determined by multivariate analysis. Mean laboratory values were plotted across illness duration. Results: Of 1215 patients, 203 (16.7%) had mild, 488 (40.2%) moderate, 183 (15.1%) severe, and 341 (28.1%) critical COVID-19 on admission. In-hospital mortality was 18.2% (0% mild, 6.1% moderate, 15.8% severe, 47.5% critical). Predictors of mortality were age ≥ 60 years, COPD, qSOFA score ≥ 2, WBC > 10 × 109/L, absolute lymphocyte count < 1000, neutrophil ≥ 70%, PaO2/FiO2 ratio ≤ 200, eGFR < 90 mL/min/1.73 m2, LDH > 600 U/L, and CRP > 12 mg/L. Non-survivors exhibited an increase in LDH and decreases in PaO2/FiO2 ratio and eGFR during the 2nd-3rd week of illness. Conclusion: The overall mortality rate was high. Predictors of mortality were similar to those of other reports globally. Marked inflammation and worsening pulmonary and renal function were evident among non-survivors by the 2nd-3rd week of illness.

Clinical characteristics of patients with asymptomatic and symptomatic COVID-19 admitted to a tertiary referral centre in the Philippines.

Objectives: To describe the clinical profile and outcomes of hospitalized patients with coronavirus disease 2019 (COVID-19) across the spectrum of disease severity. Methods: This retrospective study included adult patients with confirmed COVID-19 infection admitted to a referral hospital. Descriptive statistics, tests for trend, Kaplan-Meier curve and log-rank test were used to compare characteristics and outcomes across disease severity categories. Results: Of 1500 patients with COVID-19, 14.8% were asymptomatic, 13.5% had mild disease, 36.6% had moderate disease, 12.3% had severe disease and 22.7% had critical disease. Asymptomatic patients were admitted for a concurrent condition or for isolation. Patients aged >60 years, male gender and with co-morbidities had more severe disease. Fever, cough, shortness of breath, malaise, gastrointestinal symptoms and decreased sensorium were more common in patients with severe disease. Bilateral pulmonary infiltrates were common (51.1%), with sicker patients having more abnormal findings. The overall mortality rate was 15.1%. Adopting a symptom-based strategy reduced the length of hospitalization from a median of 13 [interquartile range (IQR) 7-21] days to 9 (IQR 5-14) days. Conclusion: The clinical profile and outcomes for this cohort of patients with COVID-19 was consistent with published reports. Asymptomatic infection was common, and universal testing may be a valuable strategy in the correct context, given the implications for infection control. A symptom-based strategy was found to reduce the length of hospitalization considerably.

Systematic review of intraoperative radiation therapy for head and neck cancer.

Multidisciplinary treatments with surgery, radiation therapy, and chemotherapy are the cornerstones in the management of locally advanced head and neck malignancies. In most cases, radiation is delivered via external beam radiation therapy (EBRT). Intraoperative radiation therapy (IORT), on the other hand, is the delivery of precise doses of radiation to selected target volumes within the exposed surgical field while at the operating room. Most studies on its use on head and neck cancers are limited to single-institutional retrospective case series. We performed a systematic review to consolidate the existing literature on IORT for head and neck malignancies. Fifty-two studies representing a mixed population of 2,389 patients were included in this review. IORT via electrons (intraoperative electron radiation therapy), brachytherapy (intraoperative high dose-rate brachytherapy) or photons was administered in numerous settings, but most commonly as part of a reirradiation regimen following salvage surgery for recurrent tumours. Often, additional EBRT was also planned postoperatively. This review illustrates that IORT is a promising treatment modality in head and neck cancer. Multiple single-institutional studies spanning several decades have demonstrated benefit in terms of local control with reasonable toxicity. However, randomised trials comparing it with current standards of care are still needed.