Contribution of 68 Ga-DOTA-FAPI-04 PET/CT to Prostate Cancer Imaging : Complementary Role in PSMA-Negative Cases.

PURPOSE: Prostate-specific membrane antigen (PSMA)-targeted PET/CT is a well-established imaging method in prostate cancer (PC) for both staging and restaging, and also for theranostic applications. An alternative imaging method is crucial for 15% PSMA-negative cases. We aimed to investigate the contribution of 68 Ga-DOTA-FAPI-04 PET/CT to PC imaging. PATIENTS AND METHODS: Thirty-six patients diagnosed with PC were included. Patients underwent both 68 Ga-PSMA PET/CT and 68 Ga-DOTA-FAPI-04 PET/CT imaging within 1 week. In staging group, primary tumor uptake values were compared, and also correlations were done with histopathological findings, MRI findings, and total PSA levels. In biochemical recurrence group, the uptake values in prostatic region and metastases were evaluated to define the local recurrence or metastatic disease. RESULTS: In staging group, PSMA PET showed increased uptake in the primary lesion area in 14/27 (52%) patients, whereas 20/27 (74%) patients were positive in FAPI-04 PET. FAPI-04 positivity was found to be quite high, such as 54%, in PSMA-negative patients. A significant difference was observed between ISUP grade 1-3 patients and ISUP grade 4-5 patients in FAPI-04 PET ( P = 0.03). Local recurrence was detected in 3 patients, pelvic lymph node metastasis in 1 patient, and sacrum metastasis in 1 patient in biochemical recurrence group, and all of the lesions had more intense uptake in PSMA PET than FAPI-04 PET. CONCLUSIONS: FAPI PET imaging seems to have a potential to contribute PSMA PET imaging with FAPI positivity in more than half of PSMA-negative cases. Also, FAPI-targeted radionuclide therapy may be a promising method in patients resistant to PSMA-targeted therapy.

68 Ga-FAPI-04 PET/CT In Primary Signet Ring-Like Cell Carcinoma of Prostate With Bone Metastases.

ABSTRACT: We presented a 69-year-old man with liver cirrhosis who underwent 68 Ga-fibroblast activation protein (FAPI)-04 PET/CT imaging for an ongoing study. In addition to the significant activity in liver cirrhosis on FAPI PET, a primary prostate tumor was incidentally detected with bone metastases. Further, FAPI-negative metastases were not observed on CT evaluation. In this context, we think that FAPI may be helpful with the potential theranostic aspect, especially in selected patients when current treatment options are not applicable or unresponsive. However, we should await the results of prospective studies investigating both prognostic and theranostic use of FAPI and demonstrating its effectiveness in cancer therapy.

18 F-FDG PET/CT in Urethral Metastases From Bladder Cancer.

ABSTRACT: Urethral metastasis of bladder cancer after surgery is rare. We present a 63-year-old man who had surgery for invasive bladder carcinoma and prostate adenocarcinoma 4 years ago and referred for urethral hemorrhage. 18 F-FDG PET/CT was performed for restaging and showed intense linear 18 F-FDG activity in the proximal urethra. The patient underwent urethrectomy, and histopathology determined urethral metastasis.

18F-FDG PET/CT and 68Ga-DOTATATE PET/CT Findings in a Patient With Primary Renal Well-Differentiated Neuroendocrine Tumor.

ABSTRACT: Primary renal well-differentiated neuroendocrine tumors (WDNETs), also called renal carcinoids, are extremely rare. Since first described in 1966, approximately 100 cases have been reported in the literature. However, there have been no cases shown by PET/CT to date. We presented a patient with primary renal WDNET who had undergone both 68Ga-DOTATATE PET/CT and 18F-FDG PET/CT for diagnosis and staging. This case illustrated that 68Ga-DOTATATE PET/CT scanning could play a role in the diagnosis, staging, and follow-up of primary renal WDNETs.

A clinical and histopathological comparison of saline, adrenaline and 2-mercaptoethanesulfonate (MESNA) in mucoperichondrial elevation: which is superior?

OBJECTIVE: To determine whether submucosal mesna (2-mercaptoethane sodium sulfonate) infiltration is superior to normal saline or adrenaline + lidocaine in mucoperichondrial hydrodissection. METHODS: Twenty-one rabbits were administered adrenaline + lidocaine, saline or mesna. Bilateral septal mucoperichondrial flap elevations were performed following submucosal infiltration. The intraoperative bleeding amount, operation time, accessibility of the surgical plane, field quality and degree of mucoperichondrial injury were recorded. The three groups were compared histopathologically. RESULTS: The amount of bleeding and duration of the operation were significantly higher and the accessibility of the surgical plane score was significantly lower in the saline group vs. the other groups (p < 0.05). The mucosal damage rate was significantly higher in the saline group compared with adrenaline + lidocaine (p < 0.05). The surgical field quality was significantly lower in the saline group compared with adrenaline + lidocaine (p < 0.05). The accessibility of the correct surgical plane score was significantly lower in the saline group compared with the adrenaline + lidocaine and mesna groups (p < 0.05). The amount of bleeding, duration of operation, surgical field quality and accessibility of the surgical plane did not differ significantly between the adrenaline + lidocaine and mesna groups (p > 0.05). The pericondrium thickness was significantly lower in the saline group than the other groups. Cartilage thickness was significantly higher in the saline group compared with the mesna group (p > 0.05). CONCLUSION: Use of mesna instead of normal saline or adrenaline + lidocaine in septoplasty was not more advantageous in terms of intraoperative parameters. The adrenaline + lidocaine group was superior to normal saline for all intraoperative parameters. In conclusion, the use of adrenaline may be more advantageous in facilitating septal mucoperichondrium elevation due to its widespread use, low cost and superiority to physiological saline.

Predictive Role of Ki-67 and Proliferative-Cell Nuclear Antigen (PCNA) in Recurrent Cholesteatoma.

OBJECTIVES: To investigate the potential use of Ki-67 and pronuclear cell antigen (PCNA) as indicators of recurrent cholesteatoma. MATERIAL AND METHODS: Patients who had been diagnosed with cholesteatoma and who had undergone canal wall-down mastoidectomy were included in this study. Subjects were divided into two groups: recurrent and non-recurrent (i.e., cases without recurrence for at least 2 years). Ossicular pathologies were recorded. Histopathologic specimens were stained for Ki-67 and PCNA and the percentages of stained cells were calculated. RESULTS: Neither group demonstrated a significant difference in terms of total Ki-67 per cell, Ki-67-stained cell counts, Ki-67-staining percentages, total PCNA per cell, PCNA-stained cell counts, or PCNA-staining percentages (p>0.05). No significant relationship was noted between the staining percentages for either Ki-67 or PCNA and the incudostapedial involvement (p>0.05); however, a significant relationship was noted between Ki-67 staining and malleus involvement (p<0.05). CONCLUSION: Although the recurrent and non-recurrent cholesteatoma groups showed no significant differences in terms of the percentages of stained cells for either Ki-67 or PCNA, we detected high Ki-67 staining in the malleus involvement group. We concluded that cell-proliferation markers could not be defined as indicators of recurrence of cholesteatoma, but they could be defined as indicators of destructive patterns of this disease.

Primary breast carcinomas with neuroendocrine features: Clinicopathological features and analysis of tumor growth patterns in 36 cases.

Primary breast carcinoma with neuroendocrine features (NEBC) is an uncommon tumor. In the classification of WHO 2012, these tumors were categorized as: 1- neuroendocrine tumor, well-differentiated; 2- neuroendocrine carcinoma, poorly differentiated/small cell carcinoma; and 3- invasive breast carcinoma with neuroendocrine differentiation. In this study, we reviewed NEBC except poorly differentiated/small cell carcinoma variant in order to define the morphological growth patterns and cytonuclear details of these tumors. All breast surgical excision materials between 2007 and 2016 were re-evaluated in terms of neuroendocrine differentiation. Thirty-six cases showing positive staining for synaptophysin and/or chromogranin A in ≥50% of tumor cells were included in the study. All cases were female with a mean age of 67.4. Mean tumor diameter was 26 mm. Multifocality was noted in 5 cases. Grossly, they were mostly infiltrative mass lesions. T stages, identified in 34 cases, were as follows: 13 cases with pT1; 19 pT2 and 2 pT3. We described schematically 4 types of patterns depending on predominant growth pattern, except one case: 1) Large-sized solid cohesive groups (6 cases), 2) Small- to medium-sized solid cohesive groups with trabeculae/ribbons and glandular structures (6 cases), 3) Mixed growth patterns (20 cases), 4) Invasive tumor with prominent extracellular and/or intracellular mucin (3 cases). The tumor cells were mostly polygonal-oval with eosinophilic/eosinophilic-granular cytoplasm. The nuclei of tumor cells were mostly round to oval with evenly distributed chromatin. Only 5 cases showed high grade nuclear and histological features. Molecular subtypes of the cases were as follows: 33 luminal A, 2 luminal B, and 1 triple negative. NEBC should come to mind when a tumor display one of the morphological patterns described above, composed of monotonous cells with mild to moderate nuclear pleomorphism and abundant eosinophilic/eosinophilic granular or clear cytoplasm, especially in elderly patients.