A case of clear cell adenocarcinoma arising from the urethral diverticulum: Utility of urinary cytology and immunohistochemistry.

Carcinomas rarely arise from the urethral diverticulum. In this report, we present a case of clear cell adenocarcinoma arising from the urethral diverticulum. A 42-year-old woman complained of bloody discharge and lower back pain. Imaging studies showed a tumor involving the region surrounding the urethra and cystourethroscopy showed papillary and villous tumors in the urethral diverticula. Cytology of the urine sediment showed papillary or spherical clusters of atypical cells, some of which had clear abundant cytoplasm and formed mirror ball-like clusters, suggesting adenocarcinoma. Although histological diagnosis was indeterminate by biopsy and transurethral resection (TUR) because of absence of stromal invasion, surgically resected specimen via cysturethrectomy revealed that the tumor was clear cell carcinoma. Urinary cytological findings and immunohistochemical analysis for CD15, Ki-67, and p53 might be useful for accurate diagnosis of clear cell adenocarcinoma that arises from the urethral diverticulum when sufficient materials are not available by biopsy and TUR.

Mucinous borderline-like tumor of the gastrointestinal type arising from mature cystic teratoma of the ovary and its immunohistochemical cytokeratin and mucin phenotype.

Malignant transformation is rarely seen in the disease course of mature cystic teratoma (MCT) of the ovary. Adenocarcinoma arising from MCT is especially rare. We herein present the case of a premenopausal woman with a mucinous borderline-like tumor arising from a MCT. Based on the histological transition between the borderline-like tumor and gastrointestinal elements of the MCT, we consider that the tumor derived from teratomatous gastrointestinal epithelium. Immunohistochemistry showed that the proliferating mucinous cells were diffusely positive for cytokeratin 20 and partially positive for cytokeratin 7. MUC5AC was partially positive, whereas MUC2 and MUC6 were positive in a small number of tumor cells. The immunophenotype of cytokeratins and mucins in the present case was compatible with malignant transformation of the teratomatous gastrointestinal epithelium.

Primary extragonadal germinoma of the medulla oblongata.

Extragonadal germ cell tumors rarely arise from the brain stem. In this report, the authors present a rare case of germinoma developing in the medulla oblongata. A 31-year-old woman complained of intractable hiccups, hoarseness, and swallowing disturbance. Magnetic resonance imaging showed a tumor located on the dorsal part of the medulla oblongata without any abnormalities in the pineal body and suprasellar regions. Histological diagnosis of surgically resected tumor was germinoma. Tumor cells were positive for alkaline phosphatase, c-kit, octamer-binding transcription factor 3/4, cytokeratin, and epithelial membrane antigen in immunohistochemistry. The patient received adjuvant chemotherapy and irradiation to the residual tumor and cerebral ventricles. The patient is alive without recurrence 6 months after the surgery.

Diagnostic performance of fluorodeoxyglucose positron emission tomography/magnetic resonance imaging fusion images of gynecological malignant tumors: comparison with positron emission tomography/computed tomography.

PURPOSE: We compared the diagnostic accuracy of fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and PET/magnetic resonance imaging (MRI) fusion images for gynecological malignancies. MATERIALS AND METHODS: A total of 31 patients with gynecological malignancies were enrolled. FDG-PET images were fused to CT, T1- and T2-weighted images (T1WI, T2WI). PET-MRI fusion was performed semiautomatically. We performed three types of evaluation to demonstrate the usefulness of PET/MRI fusion images in comparison with that of inline PET/CT as follows: depiction of the uterus and the ovarian lesions on CT or MRI mapping images (first evaluation); additional information for lesion localization with PET and mapping images (second evaluation); and the image quality of fusion on interpretation (third evaluation). RESULTS: For the first evaluation, the score for T2WI (4.68 +/- 0.65) was significantly higher than that for CT (3.54 +/- 1.02) or T1WI (3.71 +/- 0.97) (P < 0.01). For the second evaluation, the scores for the localization of FDG accumulation showing that T2WI (2.74 +/- 0.57) provided significantly more additional information for the identification of anatomical sites of FDG accumulation than did CT (2.06 +/- 0.68) or T1WI (2.23 +/- 0.61) (P < 0.01). For the third evaluation, the three-point rating scale for the patient group as a whole demonstrated that PET/T2WI (2.72 +/- 0.54) localized the lesion significantly more convincingly than PET/CT (2.23 +/- 0.50) or PET/T1WI (2.29 +/- 0.53) (P < 0.01). CONCLUSION: PET/T2WI fusion images are superior for the detection and localization of gynecological malignancies.

18F-FDG-PET in patients with malignant lymphoma having long-term follow-up: staging and restaging, and evaluation of treatment response and recurrence.

OBJECTIVE: The aim of this study was to evaluate the diagnostic accuracy of positron emission tomography (PET) with 2-[18F]fluoro-2-deoxy-D-glucose (18F-FDG) for staging/restaging, evaluating the treatment response, and screening of recurrence in patients with malignant lymphoma (ML) during long-term follow-up, and to compare that with computer tomography (CT)/magnetic resonance imaging (MRI). METHODS: The study was conducted in 59 ML patients who underwent whole-body 18F-FDG-PET examinations three times or more from October 1998 to August 2006. The location of the lesions in the patients with positive findings on 18F-FDG-PET and/or the corresponding CT/MRI was classified into supradiaphragmatic (n = 10), infradiaphragmatic (n = 7), and extranodal sites (n = 20), and the findings were compared on a site basis according to the gold standard, which consisted of all clinical information available, including follow-up results. RESULTS: A total of 156 18F-FDG-PET examinations for which the corresponding CT/MRI images were also available were evaluated, and a total of 305 sites showed positive findings on 18F-FDG-PET and/or CT/MRI. Concordant positive findings were obtained in 76% for staging/restaging, 34% for evaluation of the treatment response, and 50% for screening of recurrence. The accuracy of 18F-FDG-PET versus CT/MRI was 92% versus 84% (P = 0.06) for staging/restaging, 84% versus 50% (P < 0.05) for the evaluation of the treatment response, and 83% versus 72% (P = 0.21) for the screening of recurrence. At pathologic sites with discrepant findings between 18F-FDG-PET and CT/MRI (n = 122), the frequency of accurate diagnosis by 18F-FDG-PET (76%) was higher than that by CT/MRI (24%), especially for the evaluation of the treatment response. CONCLUSIONS: 18F-FDG-PET is expected to play a significant role in the management of ML patients even after effective treatment is initiated.

Effectiveness of real-time virtual sonography-guided radiofrequency ablation treatment for patients with hepatocellular carcinomas.

AIM: Real-time virtual sonography (RVS) can synchronize B-mode ultrasound (US) images with multiplanar reconstruction (MPR)-computed tomography (CT) images on the same screen in real time. The purpose of this study was to evaluate the effectiveness of RVS for radiofrequency ablation therapy (RFA) of hepatocellular carcinomas (HCC) in which it was difficult to identify contours or margins by B-mode US. METHODS: Sixty-three consecutive patients with a solitary HCC of less than 3.5 cm in diameter were enrolled in this study. Thirty-nine patients with HCC clearly detectable by B-mode US underwent conventional RFA, while the remaining 24 with obscure tumor lesions underwent RVS-guided RFA. A follow-up study of RFA treatment was performed every 3 months using enhanced CT imaging of the arterial and portal phase (at least 24 months). The accuracy of needle insertion was confirmed by measuring the gap between the needle insertion line and the center of the tumor from MPR-CT images. RESULTS: The local recurrence rate of the RVS-guided RFA group was similar to that of the conventional RFA group (8.3% vs 7.7%), despite the difficulty of detecting tumor lesions in the former group. The mean gap between the needle insertion line and the center of the tumor was 1.6 mm (0-3.2 mm) in eight patients treated with RVS-guided RFA. CONCLUSION: RVS-guided RFA can be useful for treating HCC that are difficult to detect by B-mode US.