Interpretable deep learning insights: Unveiling the role of 1 Gy volume on lymphopenia after radiotherapy in breast cancer.

BACKGROUND: Lymphopenia is known for its significance on poor survivals in breast cancer (BC) patients. Considering full dosimetric data, this study aimed to develop and validate predictive models for lymphopenia after radiotherapy (RT) in BC. MATERIAL AND METHODS: BC patients treated with adjuvant RT were eligible in this multicenter study. The study endpoint was lympopenia, defined as the reduction in absolute lymphocytes and graded lymphopenia after RT. The dose-volume histogram (DVH) data of related critical structures and clinical factors were taken into account for the development of dense neural network (DNN) predictive models. The developed DNN models were validated using external patient cohorts. RESULTS: Totally 918 consecutive patients with invasive BC enrolled. The training, testing, and external validating datasets consisted of 589, 203, and 126 patients, respectively. Treatment volumes at nearly all dose levels of the DVH were significant predictors for lymphopenia following RT, including volumes at very low-dose 1 Gy (V1) of organs at risk (OARs) including lung, heart and body, especially ipsilateral-lung V1. A final DNN model, combining full DVH dosimetric parameters of OARs and three key clinical factors, achieved a predictive accuracy of 75 % or higher. CONCLUSION: This study demonstrated and externally validated the significance of full dosimetric data, particularly the volume of low dose at as low as 1 Gy of critical structures on lymphopenia after radiation in BC patients. The significance of V1 deserves special attention, as modern VMAT RT technology often has a relatively high value of this parameter. Further study warranted for RT plan optimization.

Dosimetric Effect of Thymus and Thoracic Duct on Radiation-Induced Lymphopenia in Patients With Primary Lung Cancer Who Received Thoracic Radiation.

Purpose: Radiation-induced lymphopenia is a well-recognized factor for tumor control and survival in patients with cancer. This study aimed to determine the role of radiation dose to the thymus and thoracic duct on radiation-induced lymphopenia. Methods and Materials: Patients with primary lung cancer treated with thoracic radiation therapy between May 2015 and February 2020 with whole blood count data were eligible. Clinical characteristics, including age, gender, histology, stage, chemotherapy regimen, radiation dosimetry, and absolute lymphocyte count (ALC) were collected. The thymus and thoracic duct were contoured by one investigator for consistency and checked by one senior physician. The primary endpoint was radiation-induced decrease in lymphocytes, defined as the difference in ALC (DALC) before and after radiation therapy. Results: The data of a total of 116 consecutive patients were retrospectively retrieved. Significant correlations were found between DALC and several clinical factors. These factors include stage, chemotherapy or concurrent chemoradiation, biologically effective dose (BED), mean lung dose, mean body dose, effective dose to immune cells (EDIC), mean thymus dose (MTD), and mean thoracic duct dose (MTDD) (all P < .05). Ridge regression showed that DALC = 0.0063 × BED + 0.0172 × EDIC + 0.0002 × MTD + 0.0147 × MTDD + 0.2510 (overall P = .00025 and F = 5.85). The combination model has the highest area under the curve of 0.77 (P < .001) when fitting the logistic regression model on DALC categorized as binary endpoint. The sensitivity and specificity of the combined model were 89% and 58%, respectively. Conclusions: This study demonstrated for the first time that radiation doses to the thymus and thoracic duct are strongly associated with radiation-induced lymphopenia patients with lung cancer. Further validation studies are needed to implement thymus and thoracic duct as organs at risk.

Real-World Practice of Hypofractionated Radiotherapy in Patients With Invasive Breast Cancer.

PURPOSE: Application of hypofractionated radiotherapy (HFRT) is growing in patients with breast cancer (BC). This study aimed to explore a real-world practice of HFRT in early and locally advanced BC. METHODS: Patients with invasive BC between 2015 and 2019 were retrospectively reviewed. Radiotherapy (RT) was delivered by HFRT and conventionally fractionated radiotherapy (CFRT). Locoregional recurrence-free survival (LRRFS) and disease-free survival (DFS) were calculated by Kaplan-Meier curve and compared by Log-rank test. The effect of treatment modality on DFS was estimated by univariate and multivariable analyses. RESULTS: A total of 1,010 patients were included in this study, and 903 (89.4%) were treated with HFRT. At a median follow-up of 49.5 months, there was no significant difference in a 4-year cumulative incidence of LRRFS in HFRT group (1.5%) and in CFRT group (3.8%) (p = 0.23), neither in different nodal stages nor in N2-3 patients with different molecular subtypes. The 4-year DFS was 93.5% in HFRT group compared with 89.9% in CFRT group with no significant difference either (p = 0.17). Univariate and multivariable analyses also showed no significant difference in DFS between HFRT and CFRT group. However, DFS of HFRT group tended to be lower in N2-3 patients with triple negative BC compared with that of CFRT group (76.2% versus 100%). CONCLUSION: HFRT can achieve similar cumulative incidence of LRRFS and DFS in patients with BC after lumpectomy or mastectomy, and also in different nodal stage, and in locally advanced stage with different molecular subtypes.

Immune globulin-responsive thrombocytopenia in acute post-streptococcal glomerulonephritis: report of a case in Hawai'i.

A 9-year-old boy in Hawai'i presented with bleeding and thrombocytopenia and was subsequently found to have post-streptococcal glomerulonephritis. He recovered completely with intravenous immune globulin, antibiotics, short-term antihypertensive therapy, and supportive management. This case was similar to the 5 cases previously reported in the literature, with the exception that steroids were not used as the primary immune-modulating therapy.

Reasons for homelessness among Micronesians at a transitional shelter in Hawai'i.

BACKGROUND: Over 6,000 people are homeless in the State of Hawai'i and a growing number are of Micronesian descent. This study looks at reasons for homelessness in the Micronesian population. METHODS: The authors conducted a retrospective chart review of 145 patients who were seen in a free student-run medical clinic at a transitional shelter in Hawai'i. Demographics and reasons for homelessness were compiled for the patients of Micronesian ancestry. RESULTS: Of the 56% of patients that were found to be of Micronesian ancestry, overcrowded housing was the most common reason leading to homelessness. CONCLUSION: Overcrowded housing, probably caused by poverty, along with social and cultural differences, likely play a significant role in the reasons for homelessness in Micronesian migrants. More research needs to be done to discern the reasons for, attitudes towards, and solutions for homelessness in this population.

Health problems of Micronesian patients at a student-run free homeless clinic.

BACKGROUND: As of November 2006, 41.3% of the residents at a newly established transitional homeless shelter in Hawai'i were of Micronesian descent. A student-run medical clinic operates at this shelter every week. This study examines the medical problems found in the Micronesian patients at this clinic. METHODS: A retrospective chart review of 213 patients was conducted. Data was compiled from registration forms, intake forms, and progress notes. RESULTS: The most common medical conditions that patients reported having were musculoskeletal problems, hypertension, and diabetes. For actual patient encounters, health maintenance visits and acute conditions, such as upper respiratory infections, were the most frequent. CONCLUSIONS: Homeless Micronesian patients seen at this shelter presented with problems more similar to the general homeless population than for chronic conditions commonly cared for by providers of care to Micronesians in the community. More information about the health and other needs of homeless Micronesians in Hawai'i is warranted.

The cockroach as a host for Trichinella and Enterobius vermicularis: implications for public health.

Cockroaches are known carriers of bacteria and fungi that produce disease in humans. However, the link between pathogenic helminths and cockroaches has not been fully explored. This preliminary study demonstrates Trichinella and Enterobius (also known as human "pinworm") infestation in cockroaches obtained from a grade school and hospitals in Hawaii. This is the first report of Trichinella and Enterobius infestation in naturally occurring cockroaches. These results suggest that roachs are an unappreciated hosts for these human pathogens and are potential reservoirs for these nematodes, supporting their persistence and transmissibility in the environment. Given the ubiquitous nature of the cockroach and the human-occupied settings in which the infested roaches were found, public health concerns are apparent. Furthermore, this information may have diagnostic value when examining Trichinella and Enterobius-infected individuals.