Risk of Death from Pneumocystis jirovecii after Curative-intent Radiotherapy for Lung Cancer

Detection of Pneumocystis jirovecii by PCR in patients with lung cancer: A preliminary study

INTRODUCTION

Infection complications in lung cancer (LC), one of the most common cancers in the world, are still among the most important causes of death. Of them, P. jirovecii, which is as an opportunistic infection, causes a life-threatening type of pneumonia in cancer patients. This preliminary study aimed to determine the incidence and clinical status of P. jirovecii by PCR in lung cancer patients compared to the conventional method.

MATERIAL AND METHODS

Sixty-nine lung cancer patients and fSorty healthy individuals were included in the study. After sociodemographical and clinical features were recorded, sputum samples were collected from attenders. Firstly, microscopic examination was made with Gomori's methenamine silver stain and then PCR was performed.

RESULTS

P. jirovecii was detected in three of 69 lung cancer patients by PCR (4.3%), but not by microscopy. However, healthy individuals were negative for P. jirovecii by both methods. Based on clinical and radiological findings, P. jirovecii was evaluated as probable infection in one patient and colonization in the other two patients. Although PCR is more sensitive than conventional staining methods, it cannot distinguish probable and proven infections from pulmonary colonization.

DISCUSSION

It is important to evaluate the decision of infection together with laboratory, clinical and radiological findings. Moreover, PCR may enable to know the colonization and to take precautions such as prophylaxis, due to the risk of colonization turning into an infection in immunocompromised patient groups. Further studies involving larger populations and evaluating the colonization-infection relationship in patients with solid tumors are needed.

Assessment of the Implementation of Lung Cancer Consensus Statements From the Royal College of Radiologists in 2021; Progress and Barriers

BACKGROUND

Lung cancer outcomes in the UK are worse than those in many similar countries. The RCR developed a series of 43 consensus statements (CS) to facilitate improvements in care for patients treated with radiotherapy.

METHODS

We asked all 61 UK radiotherapy centres to self-assess the implementation of the CS and to describe their departmental key strengths and weaknesses in September 2021.

RESULTS

87% of centres returned their assessments. Whilst developmental activity was seen in most areas for most centres, 24 of the statements were felt to be difficult to implement within the next 2 years by at least one centre. The most frequently reported strengths were in the implementation of SABR (stereotactic body radiotherapy), concurrent chemoradiation for non-small cell lung cancer and technological aspects of treatment planning. The most frequently described departmental weaknesses were in pre-habilitation, timeliness of PET/CT scans and prophylaxis for Pneumocystis jiroveci Pneumonia (PJP). Barriers to implementation were often due to insufficient resource, a requirement for organisations to work together, and a perceived lack of evidence base. Strengths were often attributed to good team working, a local champion and being an early adopter.

CONCLUSIONS

This work confirms the commitment of lung cancer radiotherapy teams across the UK to improve outcomes for their patients. Most of the statements have been implemented at least partially. Themes have been identified to aid further progress, one of which is a requirement for significant investment.

[Pneumocystis jirovecii Pneumonia in Patients with Lung Cancer: A Review]

In recent years, with the widespread use of immunodepressant agents, Pneumocystis jirovecii pneumonia (PJP) has been significantly found in non-human immunodeficiency virus (HIV) patients, such as those with malignancies, post-transplantation and autoimmune diseases. Although the risk factors and management of PJP have been extensively studied in the hematologic tumor and post-transplant populations, the research on real tumor cases is insufficient. Lung cancer has been the most common tumor with the highest number of incidence and death worldwide, and the prognosis of lung cancer patients infected with PJP is poor in clinical practice. By reviewing the previous studies, this paper summarized the epidemiology and clinical manifestations of PJP in lung cancer patients, the risk factors and possible mechanisms of PJP infection in lung cancer patients, diagnosis and prevention, and other research progresses to provide reference for clinical application.
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Reducing the Risk of Death From Pneumocystis jirovecii Pneumonia After Radical Radiation Therapy to the Lung

AIMS

Lung cancer is the leading cause of cancer death. Radiotherapy given in the curative setting is associated with a 3% risk of death from Pneumocystis jirovecii pneumonia (PJP). Prolonged courses of high-dose steroids also increase the risk of PJP. International guidelines recommend the use of chemoprophylaxis with trimethoprim-sulfamethoxazole for patients at high risk. We assessed the effect of an intervention designed to reduce the impact of PJP.

MATERIALS AND METHODS

Prophylaxis guidelines were introduced in 2016. Case records of patients treated with radical radiotherapy were examined for the periods 2014 to 2015 (pre-intervention) and 2017 to 2018 (post-intervention). In total, 247 patients were treated pre-intervention and 334 post-intervention.

RESULTS

Freedom from PJP death at 1 year was 96% before intervention and 99% after (hazard ratio 0.3, 95% confidence interval 0.1-0.9, P = 0.029). Although the rate of use of chemoprophylaxis according to the guideline rose from 1% to 13% (P = 0.003), the use of high-dose steroids also fell from 35% to 16% (P < 0.00001).

CONCLUSIONS

Reducing radiotherapy-associated infections is an important component of radical treatment in lung cancer. Highlighting chemoprophylaxis guidelines reduced the death rate from PJP, with an associated more judicious use of steroids. Advocating prophylaxis in patients with lymphocyte count <0.6 × 109/l is the next intervention to be studied.

Radiotherapy-Related Lymphopenia Affects Overall Survival in Patients With Lung Cancer

INTRODUCTION

Lymphopenia after radiotherapy has an adverse effect on the patient's outcome. However, the relationship between radiotherapy dose delivery and lymphopenia is not fully understood. This work used image-based data mining to identify anatomical regions where the received dose is correlated with severe lymphopenia.

METHODS

A total of 901 patients with lung cancer were analyzed. A Cox model was used to assess prognostic factors of overall survival (OS). Two matched groups were defined-patients with lymphopenia of grade 3 or higher and patients without lymphopenia of grade 3-based on tumor volume, baseline lymphocytes, and prescribed dose. Then, data mining was used to identify regions where dose correlates significantly with lymphopenia of grade 3 or higher. For this, dose matrices were aligned using registration of the computed tomography images to one reference patient. Mean dose distributions were obtained for the two groups, and organs of significance were detected. Dosimetric parameters from the identified organs that had the highest correlation with lymphocytes at nadir were selected. Multivariable analysis was conducted for lymphopenia of grade 3 or higher on the full lung cohort, and the model was tested on 305 patients with esophageal cancer.

RESULTS

Adjusted Cox regression revealed that lymphopenia of grade 3 or higher is an independent factor of OS. The anatomical regions identified were the heart, lung, and thoracic vertebrae. Dosimetric parameters for lymphopenia included thoracic vertebrae V20, mean lung dose, and mean heart dose, which were further validated in the esophageal cancer cohort.

CONCLUSIONS

We report that severe lymphopenia during radiotherapy is a poor prognostic factor for OS in patients with lung cancer and could be mitigated by minimizing thoracic vertebrae V20, mean lung dose, and mean heart dose to limit the irradiation of stem cells and blood pool.

Pneumocystis jirovecii Pneumonia in a Non-small Cell Lung Cancer Patient on Chemoradiotherapy: A Case Report

Pneumocystis jirovecii pneumonia is a very uncommon complication in lung cancer patients. We report the case of a 59-year-old, Stage IIIB non-small cell lung cancer (epidermoid) patient who was receiving concurrent chemotherapy scheme (cisplatin + vinorelbine) and radiotherapy and developed fever and dyspnea not controlled with classical antibiotics. The patient developed respiratory distress. A high-resolution computed tomography showed a crazy-paving pattern, and a bronchoalveolar lavage confirmed the diagnosis of Pneumocystis jirovecii pneumonia. The patient was successfully managed with intravenous trimethoprim/sulfamethoxazole and voriconazole. Few such cases have been reported in the literature, and in most cases, the infection has been found to be associated with aggressive oncological treatments. Therefore, Pneumocystis jirovecii pneumonia should be considered in lung cancer patients with its presenting symptoms, especially if the patient is undergoing aggressive chemotherapy and/or radiotherapy.