Appendiceal mucinous neoplasms have been classified differently over time causing confusion when comparing results between working groups in this field and establishing a prognosis of the disease. A historical perspective of the different classification systems of these tumors is essential for the understanding of the evolution of concepts and histopathological definitions that have led up to the present moment. We carried out a systematic review of the pathological classifications of appendiceal mucinous tumors and how they have included the new criteria resulting from clinical and pathological research. The latest classifications by PSOGI and AJCC 8th edition Cancer Staging have made a great effort to incorporate the new pathological descriptions and develop prognostic groups. The introduction of these new classification systems has posed the challenge of verifying how they adapt to our casuistry and which one defines best the prognosis of our patients. We reclassified our series of patients treated for mucinous appendiceal tumors with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy following the PSOGI and the AJCC 8th edition criteria and concluded that both classifications correspond well with the OS and DFS of these patients, with some advantage relative to the PSOGI classification due to a better histopathological description of the different groups.

Cisplatin is one of the most widely used chemotherapeutic agents in oncology, although its nephrotoxicity limits application and dosage. We present the results of a clinical study on prophylaxis of cisplatin-induced nephrotoxicity in patients with peritoneal carcinomatosis undergoing cytoreduction and hyperthermic intraperitoneal intraoperative chemotherapy (HIPEC-cisplatin). Prophylaxis was with imipenem/cilastatin. Cilastatin is a selective inhibitor of renal dehydropeptidase I in the proximal renal tubule cells that can reduce the nephrotoxicity of cisplatin. Unfortunately, cilastatin is not currently marketed alone, and can only be administered in combination with imipenem. The study has a retrospective part that serves as a control (n = 99 patients receiving standard surgical prophylaxis) and a prospective part with imipenem/cilastatin prophylaxis corresponding to the study group (n = 85 patients). In both groups, we collected specific data on preoperative risk factors of renal damage, fluid management, hemodynamic control, and urine volume during surgery (including the hyperthermic chemotherapy perfusion), as well as data on hemodynamic and renal function during the first seven days after surgery. The main finding of the study is that cilastatin may exert a nephroprotective effect in patients with peritoneal carcinomatosis undergoing cytoreduction and hyperthermic intraperitoneal cisplatin perfusion. Creatinine values remained lower than in the control group (ANOVA test, p = 0.037). This translates into easier management of these patients in the postoperative period, with significantly shorter intensive care unit (ICU) and hospital stay.

Soft tissue sarcomas (STS) are an uncommon and biologically heterogeneous group of tumors arising from mesenchymal cells. The incidence is estimated at five cases per 100,000 people per year. Retroperitoneal sarcomas (RPS) account for 10–15% of all STS, and their management depends on their anatomical characteristics and histotype. Due to their very low incidence, it is recommended that RPS be treated in reference centers and evaluated by an experienced multidisciplinary team (MDT). In Spain, the Spanish Group for Research in Sarcomas (GEIS) brings together experts from various specialties to promote research on sarcomas and improve treatment results. This paper summarizes the GEIS recommendations for the diagnosis, treatment, and follow-up of patients with RPS.

Alvaro Gregorio Morales Taboada, Pablo Lozano Lominchar, Lorena Martin Roman, Pilar García-Alfonso, Andres Jesús Muñoz Martin, Jose Antonio Blanco Rodriguez, and Jose Manuel Asencio Pascual. Ann Hepatobiliary Pancreat Surg 2021;25:179-91. https://doi.org/10.14701/ahbps.2021.25.2.179

Background/Objectives: To review the problem of diagnostic delay in soft tissue sarcomas with the aim of identifying its causes and consequences, understanding how to clinically suspect and refer them, and evaluating the main limitations of the referral guidelines already in use. Methods: A systematic review of the available literature was performed, focusing on the theoretical framework, the elements and time intervals to be considered, causes and consequences, “red flag” symptoms/signs, the main referral guidelines in use, their results, and the methods used to avoid excessive referrals. Results: Diagnostic delay in soft tissue sarcomas is a frequent event that is poorly characterized and has important consequences, including prognostic, medico-legal and psycho-social effects. The common denominator is the lack of knowledge and awareness. Several referral guidelines have been described, and most of them are based on clinical data. Their results have been disappointing. Thus, it is necessary to implement new methods to improve their results and avoid the overload of pre-referral imaging systems, sarcoma diagnostic triage meetings, and telemedicine systems. Conclusions: Sarcoma units and health system leaders need to study this issue to determine the extent of the problem and its causes. Without this information, it is almost impossible to properly address the problem and take corrective actions. Early referral of suspected soft tissue sarcoma lesions, although desirable, is a complex issue due to the non-specificity of the symptoms. Existing clinical referral guidelines need to be modified to improve detection and conversion rates.