Usefulness of PET/CT 18-FDG for the diagnosis and follow-up of urological, urothelial and kidney tumours. / Utilidad de la PET/TC 18-FDG en diagnóstico y seguimiento de tumores urológicos uroteliales y renales.

INTRODUCTION: New imaging studies have appeared in recent years for the diagnosis and follow-up of metastatic urological tumours. MATERIAL AND METHODS: A total of 41 patients were reviewed with suspected recurrence of a urothelial or kidney tumour, analysing the diagnostic performance of PET-CT scans undertaken between 2013 and 2016. RESULTS: We collected 17 urothelial tumours and 24 renal tumours, with a median follow-up of 30 months. A total of 39.3% of the urothelial tumours were high grade and 29.3% of the kidney tumours were clear cell Fuhrman II. As a whole, the imaging studies detected recurrences in 34 patients. CT was positive in 83% of the patients, while the PET scan was positive in 75.6%, CT/PET coincidence was 50%. The PET scan detected further disease in 41% of the cases compared to 5% by CT. This resulted in a change of therapeutic strategy in 40% of the patients. Sensitivity, specificity, positive predictive value and negative predictive value for the CT and the PET scans were 92% and 92%, 57% and 100%, 92% and 100%, and 57% and 70% respectively. CONCLUSION: The PET scan showed similar sensitivity for urological tumours to the standard imaging techniques but with higher specificity, positive predictive value and negative predictive value. This led to a change in treatment strategy for 40% of the patients in our series. The PET scan will probably become the standard test in the extension and follow-up studies of most urological tumours.

Ultimate Clinical Outcomes of Appendiceal Mucinous Neoplasm of Uncertain Malignant Potential.

BACKGROUND: The clinical outcome of appendiceal mucinous neoplasm (AMN) is not well understood. This study aimed to compare the long-term outcome for the uncertain malignant potential (UMP) subtype of AMNs with those of the mucinous adenoma (MA) and mucinous adenocarcinoma (MAC) subtypes. METHODS: In this study, AMNs were classified into three groups (MA, UMP, and MAC), and clinical characteristics, overall survival (OS), and progression-free survival (PFS) were compared among the three groups. RESULTS: The study included 65 AMN patients (26 MA, 20 UMP, and 19 MAC patients). The median follow-up period was 87 months (range 0.3-311.0) months. The symptoms at diagnosis and the presence of pseudomyxoma peritonei were more common in the MAC group than in the MA group (P = 0.012) or the UMP group (P < 0.001). The 5-year OS rates were 95.5% for the MA group, 93.8% for the UMP group, and 78.3% for the MAC group (P < 0.001), and the 5-year PFS rates were 95.2% for the MA group, 95% for the UMP group, and 36.8% for the MAC group (P < 0.001). Thus, OS and PFS did not differ significantly in the MA and UMP groups (P = 0.884 and 0.345, respectively). In contrast, the OS and PFS of the MAC group were worse than in the MA group (P = 0.017 and <0.001, respectively) or the UMP group (P < 0.001 and 0.001, respectively). CONCLUSIONS: The long-term outcome for UMP tumors is similar to that for MA tumors and significantly better than for MAC tumors.

Multicenter study of serous cystic neoplasm of the Japan pancreas society.

OBJECTIVES: There have been only a few reports on follow-up results of serous cystic neoplasm (SCN) of the pancreas. The frequency of malignancy and surgical indication of SCN are not determined yet. METHODS: In this multi-institutional study of the Japan Pancreas Society, a total of 172 patients with SCN were enrolled. The mean follow-up period was 4.5 years. Surgical resection was performed in 90 patients, whereas the remaining 82 were simply observed. RESULTS: Of all patients, 20% were symptomatic. The tumor was located in the pancreatic head (39%), body (35%), and tail (22%). The mean diameter of the tumor was 4.1 cm. None of the patients showed distant or lymph node metastasis except for liver metastasis found in 2 patients (1.2%). No patient died during the follow-up. The preoperative diagnosis did not correctly identify SCN in 57 (63%) of 90 resected cases. A honeycomb appearance, which is one of the most characteristic findings of SCN, could be diagnosed better by endoscopic ultrasonography than by other imaging diagnostic modalities. CONCLUSIONS: Surgical resection should be considered only when clear distinction from other surgical diseases is difficult, when symptoms or mass effects are present, and when the tumor size is large.

Guanylyl cyclase C is a specific marker for differentiating primary and metastatic ovarian mucinous neoplasms.

AIMS: The aim was to assess the value of GCC in distinguishing primary ovarian mucinous neoplasms from metastatic mucinous adenocarcinomas with ovarian involvement. Guanylyl cyclase C (GCC) is a brush border membrane receptor for the endogenous peptides guanylin and uroguanylin, and the homologous diarrhoeagenic bacterial heat-stable enterotoxins that is selectively expressed by epithelial cells from the duodenum to the rectum, but not by normal epithelia of the stomach or oesophagus, or normal extramucosal cells in humans. METHODS AND RESULTS: Fifty ovarian tumours: 27 primary ovarian mucinous neoplasms (seven cystadenomas, 10 borderline tumours and 10 cystadenocarcinomas) and 23 metastatic mucinous adenocarcinomas with ovarian involvement [13 colorectal adenocarcinomas, four gastric adenocarcinomas, six appendiceal mucinous tumours (four adenocarcinomas, one with neuroendocrine features, and two appendiceal mucinous cystadenomas)] were studied. For primary ovarian mucinous neoplasms, 25 of 27 were negative for GCC. Twelve of 13 cases of colorectal adenocarcinoma (except for one neuroendocrine adenocarcinoma) were positive for GCC. Three of four appendiceal mucinous adenocarcinomas were positive for GCC in both the primary and metastatic tumours (except for one neuroendocrine adenocarcinoma). Two of two appendiceal mucinous cystadenomas were positive for GCC. Of four cases of gastric adenocarcinoma with ovarian involvement, only one (primary tumour) exhibited focal GCC staining. CONCLUSIONS: GCC is a useful marker for differentiating between primary and secondary ovarian mucinous neoplasms.

COX-2 expression in pseudomyxoma peritonei.

COX-2 expression was studied using an immunohistochemical method in 75 patients with pseudomyxoma peritonei (PMP). Twenty-five patients presented with disseminated peritoneal adenomucinosis (DPAM) and 50 with peritoneal mucinous carcinomatosis (PMCA). COX-2 was expressed in neoplastic mucinous epithelium of 30 cases (40%): 20 in PMCA (40%), 10 in DPAM (40%). Weak COX-2 expression was also noted in four of five patients with appendiceal mucinous neoplasms without peritoneal dissemination. In addition, COX-2 was detected in stromal, endothelial, inflammatory cells and reactive mesothelium. This preliminary information indicates a potential for the use of COX-2 inhibitors in patients with PMP.

Metastasis of small cell carcinoma of lung into an ovarian mucinous neoplasm: immunohistochemistry as a useful ancillary technique for diagnosis and classification of rare tumors.

The authors report the first case of ovarian mucinous adenocarcinoma with metastasis from a synchronous small cell neuroendocrine carcinoma of the lung. A 62-year-old white woman presented with weight loss and increased abdominal girth. She was found to have a large, complex cystic mass in the pelvis, and during the staging evaluation, a large, right pulmonary hilar mass was detected. Bronchial brushing as well as transbronchial fine-needle aspiration was diagnostic of small cell carcinoma. The patient received 3 cycles of chemotherapy with carboplatin and subsequently underwent a supracervical hysterectomy and bilateral salpingo-oophorectomy. A large, multiloculated cystic mass was found arising from the right ovary. Microscopic examination disclosed a mucinous neoplasm with both mucinous cystadenoma and mucinous papillary adenocarcinoma components. A microscopic focus of cells with "atypical" cytomorphologic features was detected within the mucinous neoplasm. Immunohistochemistry showed that group of cells to be positive for thyroid transcription factor 1 and chromogranin, confirming them to be metastasis from the pulmonary small cell neuroendocrine carcinoma. This case, in addition to being the first reported case of such metastasis, also highlights the diagnostic utility of immunohistochemistry as a reliable and very useful ancillary technique for the diagnosis of neoplasms with unusual clinical and/or histomorphologic presentations. The clinical and prognostic implications are also discussed.

[Lymphatic metastasis and VEGF-C expression in ovarian epithelial tumors].

The aim of the present study was to explore the role of vascular endothelial growth factor-C (VEGF-C) in the process of angiogenesis, lymphangiogenesis and lymphatic metastasis in epithelial ovarian tumors. In situ hybridization and immunohistochemical staining for VEGF-C were performed in 30 epithelial ovarian carcinomas, 9 borderline tumors and 26 benign cystadenomas. Endothelial cells were immunostained with anti-VEGFR-3 pAb and anti-CD31 mAb, and VEGFR-3 positive vessels and microvessel density (MVD) were assessed by image analysis. VEGF-C mRNA and protein expression in ovarian epithelial carcinomas were significantly higher than that in borderline tumors and benign cystadenomas (p < 0.05 or p < 0.01). In ovarian epithelial carcinomas, VEGF-C protein expression, VEGFR-3 positive vessels and MVD were significantly higher in the cases of clinical stage III-IV and with lymphatic metastasis than those of clinical stage I-II and without lymphatic metastasis respectively (p < 0.05 or p < 0.01), VEGFR-3 positive vessels and MVD was significantly higher in the VEGF-C protein positive tumors than negative tumors (p < 0.05), VEGFR-3 positive vessels was significantly correlated with MVD(p < 0.01). These data suggest that VEGF-C might play a role in lymphatic metastasis via lymphangiogenesis and angiogenesis in epithelial ovarian carcinomas, and VEGF-C could be used as a biologic marker of metastasis in ovarian epithelial carcinomas.