Disease volume can be estimated by preoperative imaging, although there are limitations for small lesions

Disease volume can be estimated by preoperative imaging, although there are limitations for small lesions. always obvious. This paradigm somewhat changed with the introduction of immunohistochemical demonstration of BAP1 (BRCA-1 associated protein 1). Loss of BAP1 expression supports a diagnosis of malignancy. The gold standard in treatment remains cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC). Targetable molecular pathways in MPM are being identified. An exciting obtaining was the demonstration of ALK rearrangements in a small subset of patients with MPM and it is hoped for that at least this small subgroup of patients could benefit from treatment with ALK inhibitors. First-generation tyrosine kinase inhibitors against epidermal growth factor receptor (EGFR) did not show any significant activity in MPM. In contrast, nintedanib, an angiokinase inhibitor, improved progression-free survival and bevacizumab, a humanized anti-VEGF antibody increased overall survival in patients with MPM, when administered in combination with cisplatin and pemetrexed. Ongoing immunotherapy trials will offer a possible new treatment. 71 years). Pleural mesothelioma is usually more frequent in males, while MPM is usually more frequent in females. MPM in female patients also often occurs at a younger age than MPM in male patients. The incidence of cases of MPM not related to asbestosis exposure is ORY-1001(trans) usually higher. Furthermore, the latency period between asbestos exposure and the development of mesothelioma is usually shorter in MPN (20 years), compared to pleural mesothelioma (30C40 years). The link with asbestos exposure is ORY-1001(trans) usually weaker than in pleural mesothelioma (33C50% 80%), but it does not mean that asbestos exposure is negligible: it is still the best-defined risk factor (3). Clinical findings MPM spreads predominantly expansive more than infiltrative. Symptoms are related to the extent of tumor spread within the abdominal cavity. The most frequently reported symptoms, occurring in more than 30C50% of patients, are abdominal pain and distention, partially due to ascetic fluid. Intestinal obstruction also can occur. Other symptoms include weight loss, abdominal mass, anorexia and a new onset abdominal wall hernia (4,5). Often, mesothelioma is encountered incidentally, either on cross-sectional imaging or during abdominal laparoscopy or laparotomy. The nonspecific character of the symptoms can lead to a diagnosis of MPM at a higher stage. Diagnostic imaging When a patient presents with abdominal pain and distention, computed tomography (CT) scan is usually widely accepted as a first line modality in diagnostic imaging (6). On CT scan, MPM appears as a solid, heterogeneous soft tissue mass with irregular margins, enhanced using intravenous contrast. Since MPM spreads rather expansively than infiltratively, a diffuse distribution throughout the abdominal cavity should raise suspicion of MPM. On the other hand, when no primary tumor site is found, no ORY-1001(trans) significantly enlarged lymph nodes are present and no organ metastases (e.g., liver) are seen, a diagnosis of MPM still must be considered. Most patients present with ascetic fluid. Other findings include caking, thickening or masses in the omentum or the mesenterium (6). Although MRI can be used for more accurate estimation of disease burden, the usefulness for diagnostic purposes is not yet well defined (7). Also, the role of a PET or PET/CT is usually unclear (8). A scoring system for small bowel and mesenteric involvement has been developed based on assessment by contrast enhanced CT (9). Diagnostic histopathology MPM currently presents some challenges in histopathologic diagnosis (10). At first, adequate clinical information is of utmost importance for the pathologist to at least consider the possibility of the diagnosis of MPM. Morphologically, CXCR4 there are mainly three subtypes, namely epithelioid, sarcomatoid or biphasic subtype, but a bewildering number of variants exists. Pleomorphic, deciduoid, small, vacuolated and clear cell variants have also been described. Since MPM tumor cells stain almost always with pan-cytokeratin markers, it is tempting for a pathologist to make a diagnosis of metastatic carcinoma. In a study of 244 cases of MPM, Tandon found that the most sensitive.