SEOM-GEIS clinical guideline for gastrointestinal stromal tumors (2022).

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.

A randomized phase II study to compare oxaliplatin plus 5-fluorouracil and leucovorin (FOLFOX4) versus oxaliplatin plus raltitrexed (TOMOX) as first-line chemotherapy for advanced colorectal cancer.

INTRODUCTION: The aim of this study was to compare TOMOX versus FOLFOX4 as first-line treatment of advanced colorectal cancer (CRC). MATERIALS AND METHODS: 191 chemotherapy-naïve patients were randomized to receive TOMOX or FOLFOX4. Patients were evaluated every 3 months and chemotherapy was continued until disease progression or unacceptable toxicity. Overall response rate was the primary endpoint. RESULTS: 183 patients were included in the intent-to-treat analysis (92 TOMOX and 91 FOLFOX4). Overall response rate was 45.6 and 36.3 % (p = 0.003) for TOMOX and FOLFOX4, respectively. No statistically significant differences were observed in overall survival (15.6 and 17.2 months; p = 0.475); progression-free survival (7.7 and 8.7 months; p = 0.292), and response duration (6.4 and 7.6 months; p = 0.372) for TOMOX and FOLFOX4, respectively. Grades 3 and 4 neutropenia (p < 0.0001) and leukopenia (p = 0.028) were more common with the FOLFOX4 regimen, while hepatic disorders and asthenia were higher in TOMOX group (p = ns). There were two treatment-related deaths in the FOLFOX4 arm and one in the TOMOX arm. Quality of life analysis based on the SF-36 revealed differences between the two regimens for physical and mental composite scores after 6 weeks, and for body pain and emotional role functioning after 6 and 12 weeks; all of these favored the FOLFOX4 arm (p ≤ 0.05). CONCLUSIONS: TOMOX and FOLFOX4 seem to have similar efficacy and are well tolerated in the first-line treatment for advanced CRC with different profiles of toxicity. The convenient TOMOX regimen may offer an alternative to fluoropyrimidine-based regimens.

SEOM clinical guidelines for the diagnosis and treatment of gastroenteropancreatic neuroendocrine tumours (GEP NETS).

Gastroenteropancreatic neuroendocrine tumours (GEP NETs) represent a heterogenous family of tumours with growing incidence and challenging clinical management. Unlike other solid tumours, they have the ability to secrete different peptides and neuramines that cause distinct clinical syndromes. However, many are clinically silent until advanced disease. This guideline aims to provide practical recommendations for the diagnosis and treatment of GEP NETs. Most recent histological and staging classifications, as well as available therapeutic approaches, such as surgery, locoregional therapy, peptide receptor radionuclide therapy (PRRT) and hormonal or systemic therapy, are discussed in this manuscript, including some recent relevant achievements with novel targeted agents. Clinical presentation (with or without hormonal syndrome), histological tumour features (including proliferation index (Ki-67) and the presence or not of somatostatin receptors), tumour stage, and location of primary tumour and distant metastasis are all key issues that shall be taken into consideration to properly design and integrate the most adequate therapeutic strategy.

Multimodal treatment of desmoid tumours: the significance of local control.

INTRODUCTION: Desmoid tumours are a rare group of tumours arising in the deep musculoaponeurotic structures and although they have no metastatic potential they can be locally aggressive with relapse rates of between 23-40%. Three sub-sites are reported: extra-abdominal, abdominal wall and intra-abdominal. The purpose of this study was to analyze patients with these tumours treated and followed at our institution and to determine factors influencing disease free survival. MATERIAL AND METHODS: We conducted a retrospective study of 20 patients treated between 1997 and 2009. Data was compiled to include age, gender, surgical history, familial adenomatous polyposis (FAP), contraceptives, tumour site, first-line treatment, positive margins and adjuvant radiotherapy. A descriptive and survival statistical analysis was also performed. RESULTS: Most patients were women, with a median age of 36 years, with abdominal wall involvement and treated with complete surgery without adjuvant radiotherapy. With a median follow-up of 35 months (range 0-188), local control at 5 years for any kind of treatment was 80%. Overall survival (OS) and 5-year progression-free survival (PFS) were 100% and 86%, respectively. CONCLUSION: Desmoid tumours are group of rare tumours. Although complete surgical resection remains the cornerstone of treatment for resectable lesions, there is still substantial risk of recurrence. Our outcomes are comparable to those reported in the few series published to date.