Possible abscopal effect after discontinuation of nivolumab in metastatic renal cell carcinoma

Immune checkpoint inhibitor-related adverse events: Real-world experience from a single veterans' affairs medical center

BACKGROUND

Immune checkpoint inhibitors (ICIs) are antineoplastic agents associated with a multitude of immune-related adverse events (irAEs). Available data from clinical trials include highly selective patient populations which may limit their applicability to real-world clinical practice.

METHODS

We present a retrospective cohort study of cancer patients treated with ICI therapy at the Zablocki VA Medical Center between 2014 and 2021. Information on demographics, cancer diagnosis, type of therapy, treatment duration, comorbidities, irAE type, and overall survival were collected.

RESULTS

We identified 187 patients who received at least one dose of ICI. About half the patients experienced at least one irAE, the most common categories being fatigue, pulmonary, and endocrine irAEs. Approximately half of the irAEs were diagnosed within the first three months of starting ICI therapy, and 60.38% of those who experienced irAEs discontinued ICI therapy. Patients who experienced endocrine or intestinal irAEs had a significantly longer overall survival.

CONCLUSION

Immune-related complications due to ICI therapy are common and can frequently lead to treatment discontinuation in the real-world setting. Endocrine and intestinal irAEs may correlate with improved survival. The ICI-treated patients who received palliative radiation therapy to the bone had less irAEs, possibly due to immunogenic cell death.

Abscopal effect with fever of unknown cause during radiotherapy: Two case reports and review of the literature

The abscopal effect is a rare phenomenon that is defined as regression of tumor lesions distant from irradiation targets. At our department, two cases with an abscopal effect with fever of unknown cause (FUC) and an inflammatory response during radiotherapy were encountered. Radiotherapy is a local treatment; therefore, it rarely causes systemic side effects during radiotherapy, and if a patient develops a fever during radiotherapy, it is frequently considered tumor fever. We experienced 2 cases of FUC during irradiation followed by abscopal effect. The obvious relationship between the abscopal effect and the fever remains to be clarified. However, FUC during radiotherapy may be a hint to the abscopal effect, considering that immune response and cytokines are closely related to the abscopal effect.

Abscopal Effects in Metastatic Cancer: Is a Predictive Approach Possible to Improve Individual Outcomes?

Patients with metastatic cancers often require radiotherapy (RT) as a palliative therapy for cancer pain. RT can, however, also induce systemic antitumor effects outside of the irradiated field (abscopal effects) in various cancer entities. The occurrence of the abscopal effect is associated with a specific immunological activation in response to RT-induced cell death, which is mainly seen under concomitant immune checkpoint blockade. Even if the number of reported apscopal effects has increased since the introduction of immune checkpoint inhibition, its occurrence is still considered rare and unpredictable. The cases reported so far may nevertheless allow for identifying first biomarkers and clinical patterns. We here review biomarkers that may be helpful to predict the occurrence of abscopal effects and hence to optimize therapy for patients with metastatic cancers.

[ONE COURSE OF PEMBROLIZUMAB AFTER RADIATION THERAPY WAS VERY EFFECTIVE AGAINST METASTATIC BLADDER CANCER AND CR WAS CONFIRMED: A CASE REPORT]

A 78-year-old man was referred to our institution for the evaluation of macroscopic hematuria and a bladder tumor for which we initially performed a transurethral resection of the bladder tumor. Pathological examination revealed that the tumor was a high-grade invasive urothelial carcinoma that was at least stage T2. Computed tomography scan showed a bladder carcinoma with no nodal or distant metastases. Assuming radical cystectomy, we administered two courses of neoadjuvant chemotherapy (i.e., gemcitabine and cisplatin chemotherapy). Unfortunately, the bladder tumor metastasized to the right internal iliac lymph node. We performed consolidative radiotherapy (54 Gy/ 27 fractions to the bladder area containing the right internal iliac lymph node). One month later, bilateral lung metastases and local penile infiltration appeared; thus, second-line chemotherapy (pembrolizumab) was added to the regimen. The patient rejected further chemotherapy after the first course of pembrolizumab. A computed tomography scan performed four months after one course of pembrolizumab therapy showed complete resolution of the metastatic lesions. As of this writing, 20 months after the first course of pembrolizumab, the patient continues to be in complete remission.