A rare case of Takotsubo cardiomyopathy.

BACKGROUND: The recent advent of the cyclin-dependent kinase (CDK) 4/6 inhibitors has considerably evolved hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer treatment. Palbociclib, an orally administered pyridopyrimidine derivative, was the first CDK4/6 inhibitor to be introduced into daily clinical practice in combination with classic endocrine backbone, based on progression-free survival (PFS) benefit assessed in the pivotal PALOMA series of randomized clinical trials. Regarding its safety profile, neutropenia and leukopenia are the most common and well-defined adverse effects, while cardiac complications are rather scarce. CASE REPORT: We present the rare case of a middle-aged female patient with HR+/HER2- metastatic breast cancer, without prior exposure to cardiotoxic antineoplastic agents, who developed Takotsubo cardiomyopathy (TTC) in the context of systemic therapy with palbociclib plus letrozole combination. CONCLUSIONS: Pharmacovigilance and experimental studies are warranted to confirm any causative relationship and to explore the underlying pathophysiology, respectively.

Tinzaparin Safety in Patients With Cancer and Renal Impairment: A Systematic Review.

Low-molecular-weight heparins are approved for primary and secondary venous thromboembolism prevention. Tinzaparin is the low-molecular-weight heparin with the highest average molecular weight. The purpose of this systematic review is to provide an update regarding the safety profile of tinzaparin, prescribed either as a prophylactic or as a therapeutic regimen for venous thromboembolism in special populations, including cancer patients and patients with renal impairment. We identified prospective studies up to August 2020 reporting safety outcomes for cancer patients and patients with renal impairment on tinzaparin regimens. In patients with cancer major bleeding rates fluctuated between 0.8% and 7%. Patients on tinzaparin exhibited significantly lower rates of clinically relevant nonmajor bleeding events in comparison with those on vitamin K antagonists. Bioaccumulation of tinzaparin was not correlated with age, body weight or creatinine clearance. Periodic administration of either prophylactic or therapeutic doses of tinzaparin did not result in bioaccumulation, even in patients with severe renal impairment and creatinine clearance < 20 ml/min. Major bleeding rates for non-cancer patients with renal impairment on prophylactic tinzaparin regimens were 0%. Non-cancer patients with renal impairment on therapeutic tinzaparin regimens exhibited major bleeding in 0 to 3.4% of cases; major bleeding rates were higher for cancer patients with renal impairment on therapeutic tinzaparin regimens (4.3 to 10%). Tinzaparin can be used without dose adjustment in patients with severe renal impairment and creatinine clearance > 20 ml/min. Tinzaparin represents a safe choice for special populations at increased risk for thrombosis and bleeding.