Epithelial-to-mesenchymal transition (EMT) represents conversion of an epithelial cell in an elongated cell with mesenchymal phenotype, which can occur in physiologic and pathologic processes such as embryogenesis (type 1 EMT), wound healing and/or fibrosis (type 2 EMT) and malignant tumors (type 3 EMT). The proliferation rate, metastasizing and recurrence capacity, as also the individualized response at chemotherapics, in both epithelial and mesenchymal malignant tumors is known to be influenced by reversible switch between EMT and mesenchymal-to-epithelial transition (MET). Although much research work has already been done in these fields, the specific molecular pathways of EMT, relating to the tumor type and tumor localization, are yet to be elucidated. In this paper, based on the literature and personal experience of the authors, an update in the field of EMT vs MET in epithelial and mesenchymal tumors is presented. The authors tried to present the latest data about the particularities of these processes, and also of the so-called endothelial-to-mesenchymal transition, based on tumor location. The EMT-angiogenesis link is discussed as a possible valuable parameter for clinical follow-up and targeted therapeutic oncologic management. The paper begins with presentation of the basic aspects of EMT, its classification and assessment possibilities, and concludes with prognostic and therapeutic perspectives. The particularities of EMT and MET in gastric and colorectal carcinomas, pancreatic cancer, hepatocellular and cholangiocarcinomas, and lung, breast and prostate cancers, respectively in sarcomas and gastrointestinal stromal tumors are presented in detail.

A 65-year-old previously healthy male heavy smoker was hospitalized with a 2-week history of progressive muscle weakness in the lower and upper extremities. After 10 days of hospitalization, urinary sphincter incompetence and fecal incontinence were added and tetraparesis was established. The computer-tomography scan examination revealed a massive right hydrothorax and multifocal solid acinar structures with peripheral localization in the left lung, which suggested pulmonary cancer. Bone marrow metastases were also suspected. Based on the examination results, the final diagnosis was acute paraneoplastic axonal Guillain-Barre-like syndrome. The patient died 3 weeks after hospitalization. At autopsy, bronchopneumonia and a right hydrothorax were confirmed. Several 4 to 5-mm-sized round peripherally located white nodules were identified in the left lung, without any central tumor mass. Under microscope, a coin-shaped peripheral/subpleural small cell carcinoma was diagnosed, with generalized bone metastases. A huge thrombus in the abdominal aorta and acute pancreatitis was also seen at autopsy. This case highlights the difficulty of diagnosis of lung carcinomas and the necessity of a complex differential diagnosis of severe progressive ascending neuropathies. This is the 6th reported case of small cell lung cancer-associated acute Guillain-Barre-like syndrome and the first report about an association with a coin-like peripheral pattern.

Intestinal tuberculosis (TB) is an uncommon lesion for which differential diagnosis can be difficult. We present a case of a 53-year-old male and a systematic review of the literature, from clinical symptoms to differential diagnosis, unusual complications and therapy. The patient was admitted to the hospital with signs of acute abdomen as a result of a perforated terminal ileitis. Based on the skip lesions of the terminal ileum and cecum, Crohn’s disease (CD) was clinically suspected. An emergency laparotomy and right colectomy with terminal ileum resection was performed and systematic antibiotherapy was prescribed. The patient’s status deteriorated and he died 4 d after the surgical intervention. At the autopsy, TB ileotyphlitis was discovered. The clinical criteria of the differential diagnosis between intestinal TB and CD are not very well established. Despite the large amount of published articles on this subject, only 50 papers present new data regarding intestinal TB. Based on these studies and our experience, we present an update focused on the differential diagnosis and therapy of intestinal TB. We highlight the importance of considering intestinal TB as a differential diagnosis for inflammatory bowel disease. Despite the modern techniques of diagnosis and therapy, the fulminant evolution of TB can still lead to a patient’s death.

Atypical hepatocellular neoplasm (AHN) is an adenoma-like hepatic tumor that even occurs in noncirrhotic liver of males (any age) or females ≥50 years old, or associates focal atypical features.In this article, 2 unusual cases diagnosed in elderly cirrhotic patients, unrelated to steroids, are presented.The first case was incidentally diagnosed in an 83-year-old female. During laparoscopic surgery for cholecystectomy, hemoperitoneum was installed and laparotomy was necessary to remove a 70-mm nodular encapsulated hepatic tumor that was microscopically composed by hepatocyte-like cells with clear cytoplasm, arranged in 1- to 2-cell-thick plates and intermingled with areas of peliosis, negative for alpha fetoprotein (αFP), p53, and keratin 7, with low Ki67 index and intact reticulin framework. The second case was incidentally diagnosed at ultrasound examination in a 66-year-old male. The surgical specimen was a 50-mm solid multinodular tumor that microscopically consisted of 3-cell-thick plates of hepatocyte-like cells with acinar, pseudoglandular, and trabecular architecture, intermingled with peliotic areas, without nuclear atypia and disintegrated reticulin framework. Both of the cases occurred in cirrhotic liver. The tumor cells were marked by AE1/AE3 keratin, displayed a Ki67 index < 5% and were negative for αFP, p53, and keratin 7. No recurrences or any other disorder occurred 6 months after surgery.In cirrhotic liver, adenomas with peliosis that do not satisfy all the diagnosis criteria synthesized in the article should be considered AHNs and differential diagnosis includes hepatocellular carcinoma but also focal nodular hyperplasia, regenerative nodules, and dysplastic nodules. This histological entity is not yet included in the WHO Classification list.