Comparison of patient characteristics and long‐term mortality between transferred and non‐transferred COVID‐19 patients in Dutch Intensive Care Units; A national cohort study

Background

COVID‐19 patients were often transferred to other intensive care units (ICUs) to prevent that ICUs would reach their maximum capacity. However, transferring ICU patients is not free of risk. We aim to compare the characteristics and outcomes of transferred versus non‐transferred COVID‐19 ICU patients in the Netherlands.

Methods

We included adult COVID‐19 patients admitted to Dutch ICUs between March 1, 2020 and July 1, 2021. We compared the patient characteristics and outcomes of non‐transferred and transferred patients and used a Directed Acyclic Graph to identify potential confounders in the relationship between transfer and mortality. We used these confounders in a Cox regression model with left truncation at the day of transfer to analyze the effect of transfers on mortality during the 180 days after ICU admission.

Results

We included 10,209 patients: 7395 non‐transferred and 2814 (27.6%) transferred patients. In both groups, the median age was 64 years. Transferred patients were mostly ventilated at ICU admission (83.7% vs. 56.2%) and included a larger proportion of low‐risk patients (70.3% vs. 66.5% with mortality risk <30%). After adjusting for age, APACHE IV mortality probability, BMI, mechanical ventilation, and vasoactive medication use, the hazard of mortality during the first 180 days was similar for transferred patients compared to non‐transferred patients (HR [95% CI] = 0.99 [0.91–1.08]).

Conclusions

Transferred COVID‐19 patients are more often mechanically ventilated and are less severely ill compared to non‐transferred patients. Furthermore, transferring critically ill COVID‐19 patients in the Netherlands is not associated with mortality during the first 180 days after ICU admission.

Gallium-67 as a Tumor-seeking Agent in Lymphomas - a Review

Background

At present 67Ga can be considered one of the most widely used viability radiotracers. There is general consensus in the literature that 67Ga has the highest clinical value in the management of lymphoma patients.

Methods

We critically discuss the role of gallium scintigraphy in lymphoma patients on the basis of the experience of the Nuclear Medicine Division at the National Cancer Institute of Milan.

Results and Conclusions

The sensitivity of gallium scan is very high (80-90%) in the staging and follow-up of Hodgkin's disease, and the method is also of great importance in the follow-up of lymphoma patients. We recommend scintigraphy to study the residual mediastinal mass after treatment. Our experiences during the follow-up of 189 lymphoma patients clearly showed the superior performance of gallium scan compared to MRI in the study of the mediastinal region after treatment. Sensitivity and specificity were both very high (90% and 96.9% vs 88.7% and 89.2%, respectively). Gallium scintigraphy can also be used to study the disease-free interval, posttreatment survival, early signs of recurrence and treatment response times. Comparison of the survival curves of 33 patients with diffuse large cell Non-Hodgkin's lymphoma examined at the National Cancer Institute showed a statistically significant difference (logrank test, P=0.0125) between patients with positive and those with negative gallium scan after 4-6 cycles of chemotherapy.

Positron emission tomography with 2-[18F]-fluoro-2-deoxy-D-glucose in oncology. Part IIIb: Therapy response monitoring in colorectal and lung tumours, head and neck cancer, hepatocellular carcinoma and sarcoma

Positron emission tomography (PET) using 18F-fluorodeoxyglucose (FDG) is considered to be a very useful adjunct to anatomic imaging techniques and is now primarily used for oncological indications. These indications include diagnosis, staging, and therapy monitoring. In this review, we discuss the articles in which FDG-PET is clinically used for monitoring therapy in lung and colorectal tumours, head and neck cancer, sarcoma, and hepatocellular carcinoma. It is found that the amount of FDG uptake strongly correlates with response to therapy: a decrease in FDG uptake after therapy indicates a positive response to therapy. However, this conclusion is based on small numbers of patients, whereas the exact response mechanism is still unknown. Moreover, in these case series, the interval between tumour therapy and FDG-PET, as well as the method of quantification, SUV or tumour-to-non-tumour ratios, differ per study. Finally, dynamic imaging is a recommended technique by some authors, but it is not a standard technique in clinical practice to evaluate tumour therapy. Therefore, further study is required which has to deal with these major issues before it is possible to draw definite conclusions.

Nuclear medicine approaches for detection of axillary lymph node metastases

In breast cancer patients the detection of axillary lymph node involvement is a very critical issue, in view of the earlier diagnosis of the disease in recent years, and the increased frequency of very small tumors at first presentation. The size of cancer is related to the risk of axillary metastases, and this may affect the prognosis and the therapeutic strategies. Axillary lymph node involvement is generally recognized as an index of distant microdiffusion, and as it affects overall and disease-free survival, represents the basis for adoption of adjuvant chemotherapy. Routine axillary lymph node dissection (ALND) is expensive, and does not benefit about 70% of early breast cancer patients which are node negative (pN-). Today most of these patients have to sustain the potential morbidity and the economic costs of ALND. The clinical approach is known to be an unreliable diagnostic tool, and for the detection of axillary metastases, conventional X-ray techniques are also unable to solve the problem. By contrast, nuclear medicine procedures have revealed a very interesting diagnostic potential in recent years. This paper analyzes the numerous studies conducted in the field of lymph node visualization and the heterogeneity of the published experiences, taking into account the different approaches proposed in the literature: a) imaging with gamma-emitting tumor seeking agents; b) radioimmunoscintigraphy intravenous (i.v.) or by the interstitial route; c) lymphoscintigraphy with colloids and gamma probe sentinel biopsy; d) positron emission tomography (PET). Although it is very difficult to make a definitive statement about the clinical efficacy of all these methods, this paper reports the most important series of patients examined in the literature as well as the author's own experiences. This can serve as the basis for a better understanding of the potential of nuclear medicine procedures, and gives the reader the opportunity to weigh advantages and drawbacks of each method. At present, lymphoscintigraphy with gamma probe sentinel biopsy and FDG-PET are the nuclear medicine approaches with the best diagnostic performance. However, a correct comparison of the methods will not be possible, until their careful assessment in the same patients is performed. In addition, a final statement today should consider also the increasing need to carry out an economic analysis by evaluating the cost-effectiveness of the examinations.