Misdiagnosis of severe and atypical oxaliplatin­related hypersensitivity reaction following chemotherapy combined with PD­1 inhibitor: A case report and literature review.

Although the efficacy of treatment strategies for cancer have been improving steadily over the past decade, the adverse event profile following such treatments has also become increasingly complex. The present report described the case of a 67-year-old male patient with gastric stump carcinoma with liver invasion. The patient was treated with oxaliplatin and capecitabine (CAPEOX regimen) chemotherapy, combined with the programmed cell death protein-1 (PD-1) inhibitor tislelizumab. Following treatment, the patient suffered from chills, high fever and facial flushing, followed by shock. Relevant examination results revealed severe multiple organ damage, as well as a significant elevation in IL-6 and procalcitonin (PCT) levels. Initially, the patient was diagnosed with either immune-related adverse events (irAEs) associated with cytokine release syndrome caused by tislelizumab or severe bacterial infection. However, when tislelizumab treatment was stopped and the CAPEOX chemotherapy regimen was reapplied, similar symptoms recurred. Following screening, it was finally determined that severe hypersensitivity reaction (HSR) caused by oxaliplatin was the cause underlying these symptoms. A literature review was then performed, which found that severe oxaliplatin-related HSR is rare, rendering the present case atypical. The present case exhibited no common HSR symptoms, such as cutaneous and respiratory symptoms. However, the patient suffered from serious multiple organ damage, which was misdiagnosed as irAE when oxaliplatin chemotherapy combined with the PD-1 inhibitor was administered. In addition, this apparent severe oxaliplatin-related HSR caused a significant increase in PCT levels, which was misdiagnosed as severe bacterial infection and prevented the use of glucocorticoids. This, in turn, aggravated the damage in this patient.

Trastuzumab, leuprorelin, letrozole, and palbociclib as first-line therapy in HER2-positive and hormone receptor-positive metastatic breast cancer: A case report.

RATIONALE: Cyclin-dependent kinase 4/6 inhibitors are promising candidates for patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer. However, current international guidelines recommend endocrine therapy alone or with HER2-targeted therapy to treat HER2-positive and hormone receptor (HR)-positive metastatic breast cancer in patients who cannot tolerate first-line chemotherapy. Moreover, data on the effectiveness and safety of cyclin-dependent kinase 4/6 inhibitors combined with trastuzumab and endocrine therapy as a first-line treatment for HER2-positive and HR-positive metastatic breast cancer are limited. PATIENT CONCERNS: A 50-year-old premenopausal woman was with epigastric pain for more than 20 days. Ten years ago, she was diagnosed with left breast cancer and underwent surgical treatment, chemotherapy, and endocrine therapy. DIAGNOSES: After relevant examination, the patient was diagnosed with liver, lung, and left cervical lymph node metastatic HER2-positive and HR-positive carcinoma from the left breast after systemic therapy. INTERVENTIONS: The laboratory investigations showed that the patient's liver function was seriously damaged due to the liver metastases, and the patient was assessed as unable to tolerate chemotherapy. She was treated with trastuzumab, leuprorelin, letrozole, and piperacillin combined with percutaneous transhepatic cholangic drainage. OUTCOMES: The patient's symptoms were relieved, her liver function returned to normal, and the tumor showed partial response. Neutropenia (Grade 3) and thrombocytopenia (Grade 2) occurred during treatment but improved after symptomatic treatment. To date, the progression-free survival of the patient is over 14 months. LESSONS: We believe that trastuzumab, leuprorelin, letrozole, and palbociclib is a feasible and effective treatment for HER2-positive and HR-positive metastatic breast cancer in premenopausal patients who cannot tolerate first-line chemotherapy.

Effect of total body X-ray irradiation on lymph node in Tibet minipig.

The purpose of this study was to determine the time-dose-effect of total body X-ray irradiation on lymphocytes in lymph nodes and peripheral blood in Tibet minipigs. Forty-eight Tibet minipigs were assigned into 6 groups including 5 experimental groups with 9 and the control group with 3. The minipigs in experimental groups were subjected to a total body X-ray irradiation of 2, 5, 8, 11, and 14 Gy respectively. Lymph nodes and peripheral blood samples were collected at 6, 24, and 72 hours after X-ray exposure and received histological microscopy examination and apoptosis analysis. Histology observation showed that the number of lymphocytes decreased within the lymph nodes with the increase of radiation doses and exposure time. The observation of transmission electron microscopy (TEM) showed typical apoptotic cells below 11 Gy while at 14 Gy necrotic cells were dominant. The apoptotic rate of lymphocytes in the lymph nodes was positively correlated with radiation dose in the range of 2-11 Gy, and reached the maximal level (39.4 ± 2.8) at 24 hours after 11 Gy irradiation, followed by a decrease in the apoptotic rate, but still higher than that of the control group. The number of lymphocytes in the peripheral blood samples was decreased significantly by increasing of the radiation dose and exposure time. We conclude that early damage of lymphocytes by total body X-ray irradiation is dose and time dependent below 11 Gy and before 24 hours post irradiation, and that the dosage of irradiation less than 11 Gy induced apoptosis, whereas the dose at 14 Gy resulted in necrosis in lymphocytes of the lymph nodes.