In 2011, the Spanish Society of Medical Oncology (SEOM) first published a clinical guideline of venous thromboembolism (VTE) and cancer. This guideline was updated in 2014, and since then, multiple studies and clinical trials have changed the landscape of the treatment and prophylaxis of VTE in cancer patients. To incorporate the most recent evidence, including data from direct oral anticoagulants (DOACs) randomized clinical trials, SEOM presents a new update of the guideline.

Soft-tissue sarcomas constitute an uncommon and heterogeneous group of tumors of mesenchymal origin. Diagnosis, treatment, and management should be performed by an expert multidisciplinary team. MRI/CT of the primary tumor and biopsy is mandatory before any treatment. Wide surgical resection with tumor-free tissue margin is the mainstay for localized disease. Radiotherapy is indicated in large, deep, high-grade tumors, or after marginal resection not suitable for re-excision. Perioperative chemotherapy should be discussed for high-risk sarcomas of the extremities and trunk-wall. In the case of oligometastatic disease, patients should be considered for local therapies. First-line treatment with anthracyclines (or in combination with ifosfamide) is the treatment of choice. Other drugs have shown activity in second-line therapy and in specific histological subtypes but options are limited and thus, a clinical trial should always be discussed.

Gastrointestinal stromal tumor (GIST) is the most common malignant neoplasm of mesenchymal origin, and a paradigmatic model for a successful rational development of targeted therapies in cancer. The introduction of tyrosine kinase inhibitors with activity against KIT/PDGFRA in both localized and advanced stages has remarkably improved the survival in a disease formerly deemed resistant to all systemic therapies. These guidelines are elaborated by the conjoint effort of the Spanish Society of Medical Oncology (SEOM) and the Spanish Sarcoma Research Group (GEIS) and provide a multidisciplinary and updated consensus for the diagnosis and treatment of GIST patients. We strongly encourage that the managing of these patients should be performed within multidisciplinary teams in reference centers.

Background: The prospective phase IV AVAMET study was undertaken to correlate response evaluation criteria in solid tumors (RECIST)-defined response rates with computed tomography-based morphological criteria (CTMC) and pathological response after liver resection of colorectal cancer metastases. Methods: Eligible patients were aged ≥18 years, with Eastern Cooperative Oncology Group (ECOG) performance status 0/1 and histologically-confirmed colon or rectal adenocarcinoma with measurable liver metastases. Preoperative treatment was bevacizumab (7.5 mg on day 1) + XELOX (oxaliplatin 130 mg/m², capecitabine 1000 mg/m² bid on days 1–14 q3w). After three cycles, response was evaluated by a multidisciplinary team. Patients who were progression-free and metastasectomy candidates received one cycle of XELOX before undergoing surgery 3–5 weeks later, followed by four cycles of bevacizumab + XELOX. Results: A total of 83 patients entered the study; 68 were eligible for RECIST, 67 for CTMC, and 51 for pathological response evaluation. Of these patients, 49% had a complete or partial RECIST response, 91% had an optimal or incomplete CTMC response, and 81% had a complete or major pathological response. CTMC response predicted 37 of 41 pathological responses versus 23 of 41 responses predicted using RECIST (p = 0.008). Kappa coefficients indicated a lack of correlation between the results of RECIST and morphological responses and between morphological and pathological response rates. Conclusion: CTMC may represent a better marker of pathological response to bevacizumab + XELOX than RECIST in patients with potentially-resectable CRC liver metastases.

Trastuzumab therapy has dramatically changed breast cancer prognosis. Consensus documents recommend a close monitoring during therapy, not always feasible, especially in metastatic breast cancer. The purpose of this study is to describe trastuzumab cardiotoxicity in metastatic breast cancer patients to understand how to improve cardiovascular monitoring. We retrospectively studied metastatic breast cancer patients scheduled for trastuzumab therapy (2001-2018). All patients underwent a baseline evaluation and monitoring during therapy. Cardiotoxicity was defined as symptomatic heart failure or asymptomatic decrease in left ventricular ejection fraction > 10% from baseline and < 53%. Ninety-two women were included, mean age 61 years (±14.43), median follow-up 42.5 months (IQR 26-74). Fourteen percent developed cardiotoxicity: two heart failure with preserved left ventricular ejection fraction, three heart failure with reduced left ventricular ejection fraction, and eight asymptomatic decreased in left ventricular ejection fraction. Eighty-one percent of cardiac dysfunction cases occurred within the first 4 years and on median of 31 months from trastuzumab initiation. Thus, in metastatic breast cancer patients, trastuzumab-mediated cardiotoxicity occurred more frequently during the first 4 years. These data should be considered to optimize follow-up protocols.