18F-FDG-PET/CT findings of retroperitoneal tumors: a pictorial essay

A variety of different tumors can arise from any of the tissues present in the retroperitoneum, and they exhibit a wide range of pathologic types. Although computed tomography (CT) and magnetic resonance imaging (MRI) can demonstrate important characteristics of these tumors, diagnosis is often challenging for radiologists. The purpose of this pictorial essay is to review ¹⁸F-fluorodeoxyglucose positron emission tomography/CT (FDG-PET/CT) features of different kinds of benign and malignant retroperitoneal tumors in comparison with CT or MRI findings alone and to become familiar with the wide variety of imaging characteristics.     

Outcome of patients with reactive amyloidosis associated with rheumatoid arthritis in dialysis treatment

The aim was to analyze the clinical outcome of a group of 51 patients diagnosed with systemic amyloidosis associated with rheumatoid arthritis who received hemodialysis (HD) as renal replacement therapy. We monitored the clinical course of the disease and factors that could influence survival. Determination of the onset of the underlying disorder was made retrospectively by reviewing the patient’s chart when a diagnosis of amyloid was confirmed. During a 96.9 person-year follow-up, 42 patients died. Survival of these 51 patients from the initiation of HD at 251 days was 50%. Poor prognosis in amyloid patients was mainly due to a large number of sudden deaths immediately following HD therapy. Out of 51 patients 21 needed unplanned initiation of HD. The unplanned initiation was significantly associated with poor survival. Seventy-five percentile of creatinine clearance (Ccr) was 9.7 ml/min, and 75% of these patients who initiated HD had highly impaired renal functional states. These data indicated that amyloidotic patients with HD showed a high mortality rate; therefore, planned initiation of HD was highly recommended to improve the patient’s survival. Particular attention was given to the Ccr levels, because the levels of serum creatinine may not be a useful marker for some patients with amyloidosis.     

An essential dose of cisplatin for super-selective intra-arterial infusion concomitant with radiotherapy in patient with maxillary squamous cell carcinoma

The present study investigated the efficacy and safety of using a lower dose of cisplatin (CDDP) in super-selective intra-arterial concurrent chemoradiotherapy (SSIACRT) to treat maxillary squamous cell carcinoma. 10 patients with maxillary squamous cell carcinoma (T3 n?=?6, T4a n?=?4) without regional or distant metastasis were treated by SSIACRT. The CDDP dose per course was 100?mg/body, i.e. 50–80?mg/m². 6–9?weeks after SSIACRT, partial maxillectomy was performed on all patients. Clinical and histological responses, survival rates, and adverse events were investigated. 10 (100%) of 10 patients achieved both clinical and pathological complete or partial remission. The 3-year overall and disease-free survival rates were 100 and 90%, respectively. Grade 3 toxicity was experienced by two patients. In conclusion, the SSIACRT regimen with a lower dose of CDDP (100?mg/body) had an equivalent therapeutic outcome and lower toxic outcome compared to a higher dose of CDDP. This regimen could be an effective and safe therapeutic modality for maxillary squamous cell carcinoma except T4b and N1/2 disease.     

Overexpression of the orotate phosphoribosyl-transferase gene enhances the effect of 5-fluorouracil on gastric cancer cell lines

OBJECTIVE: Orotate phosphoribosyl-transferase (OPRT) is the initial enzyme of the 5-fluorouracil (5-FU) metabolic pathway, converting 5-FU into 5-fluorouridinemonophosphate, which is the most important mechanism of 5-FU activation. We therefore investigated whether overexpression of the OPRT gene enhances sensitivity to 5-FU. METHODS: An expression vector of the OPRT gene (pTARGET-OPRT) was transfected into two gastric cancer cell lines, TMK-1 and MKN-45, with low baseline expression levels of OPRT. The sensitivity to and anti-tumor activity of 5-FU were then investigated in vitro and in vivo in these two transfected clones (TMK-OPRT and MKN-OPRT). RESULTS: Although cell growth was unaltered compared to parent cells, overexpression of the OPRT gene was confirmed by Western blotting in both the TMK-OPRT and MKN-OPRT cells. OPRT enzyme activity increased 38-fold in TMK-OPRT cells and 8.0 fold in MKN-OPRT cells compared to their parent cells. Interestingly, although the sensitivity to Adriamycin, cis-platinum, mitomycin C and paclitaxel was unaltered in the transfected clones, the sensitivity to 5-FU was increased 14.2- and 6.0-fold in TMK-OPRT and MKN-OPRT cells, respectively, compared to their parent cells. Moreover, enhanced sensitivity was also confirmed in the in vivo study. CONCLUSION: The results indicate that overexpression of the OPRT gene plays an important role in the antiproliferative effect of 5-FU and might therefore be a predictive factor of response to 5-FU in gastric cancer patients.     

Mechanisms for sickle red blood cell retention in choroid

PURPOSE: Although sickle (SS) red cell-mediated vaso-occlusion in retina and resultant retinopathy is well documented, the effects of SS red cells on choroidal vasculature are poorly understood. The intent of this study was to determine, using a rat model, the conditions under which retention of sickle erythrocytes in choroid occur and if that retention can be inhibited. METHODS: Sickle red cells were density separated into high density (SS4) or normal density, reticulocyte-enriched fractions (SS2). Red cells were labeled with FITC and administered IV to anesthetized Sprague Dawley rats. Rats were made either hypoxic or were given TNF-alpha intraperitoneally 5 hours before intravenous administration of red cells. Five minutes after administration of red cells, rats were exsanguinated, the retinas removed, and choroids prepared as flatmounts. The number of red cells retained in five high power fields of choroid was then determined. In other experiments, SS red cells were preincubated with the cyclic peptide TBC772 [inhibits binding of alpha4beta1 (VLA-4) and alpha4beta7 to their ligands], a control peptide TBC1194, or a VLA-4 neutralizing antibody before administration to the rat or antibodies against VLA-4 ligands were delivered IV before administration of SS red cells. RESULTS: Hypoxic conditions before administration of SS red cells significantly stimulated retention of SS4 cells (P = 0.0003), but did not significantly increase retention of SS2 cells. Administration of TNF-alpha significantly increased retention of all types of SS red cells (P < 0.001). Preincubation of cells with anti-VLA-4 or TBC 772 inhibited retention of SS red cells in choriocapillaris of TNF-alpha-treated rats (P < 0.0001). Complete inhibition of cytokine-stimulated retention was also accomplished by IV administration of monoclonal antibodies against fibronectin or its CS-1 domain, a ligand for VLA-4. CONCLUSIONS: The mechanisms for retention of SS red cells in retina and choroid appear identical: hypoxia-mediated retention of dense red cells and adherence of red cells in reticulocyte-rich fractions after cytokine stimulation. TNF-alpha-stimulated retention of SS red cells in choroid appears to be mediated by VLA-4, presumably on the surface of some reticulocytes. This increased retention was inhibited by a VLA-4 antagonist (TBC772), a VLA-4 neutralizing antibody or by blocking one of VLA-4's ligands, the CS-1 portion of fibronectin.     

Combination of intravascular surgery and surgical operation for occipital subcutaneous arteriovenous fistula in a patient with neurofibromatosis type I

We presented a case of neurofibromatosis type I (NF-1) associated with an extracranial arteriovenous fistula (AVF) fed by the occipital and vertebral artery. A 20-year-old man was referred to our hospital because of an occipital subcutaneous pulsatile mass. A CT scan showed a huge subcutaneous enhanced mass. Angiography revealed that the occipital AVF was fed by bilateral occipital arteries, the left ascending pharyngeal artery, the left middle cerebral artery, and the left vertebral artery with-abundant communication with the subcutaneous veins. Endovascular treatment by using both coil and glue (Eudragid) embolization via the occipital artery successfully obliterated the AVF. Subsequently surgical operation was performed. Postoperative angiography showed the disappearance of the AVF. Combination of intravascular surgery and surgical operation should be considered as an effective treatment for NF-1 associated with AVF.     

Medulloblastomas in childhood: histological factors influencing patients' outcome

Sixty-five medulloblastomas in infancy and childhood treated from 1965 through 1981 were reviewed, and the correlation between histological findings of medulloblastomas and clinical course of the patients was studied. Thirty-five patients died but the remaining 30 are alive and without clinical evidence of recurrence 5 years or more after surgery. Certain histological features on light microscopic examinations (e.g., pleomorphism of tumor cells, nuclear-cytoplasmic ratio, mitotic index, degree of vascularity and endothelial proliferation) do influence patient outcome with statistical significance (P<0.05). Thirty out of 65 medulloblastomas were examined further, using immunohistochemical methods with glial fibrillary acidic protein (GFAP), neuron specific enolase (NSE), and factor VIII/vW factor (F VIII/vWF). GFAP stain was negative in 20%, NSE stain in 13.3% and F VIII/vWF stain in 16.7% of the medulloblastomas studied. Desmoplastic medulloblastomas showed a strong tendency toward positive NSE and GFAP staining in the glomerular portion. There was no correlation between patient outcome and the results of applied immunohistochemical studies. Our data indicate that certain histological features may influence patient outcome, but the degree and pattern of cellular differentiation do not predict outcome.     

Giant carotid-ophthalmic artery aneurysms: direct clipping utilizing the "trapping-evacuation" technique

The authors have devised a "trapping-evacuation" technique to facilitate direct clipping of giant aneurysms in the paraophthalmic region of the internal carotid artery (ICA). The giant aneurysm is collapsed by first trapping the aneurysm by temporary occlusion of the cervical common carotid and external carotid arteries, along with temporary clipping of the intracranial ICA distal to the aneurysm. Thereafter, intra-aneurysmal blood is simultaneously aspirated through a catheter placed in the cervical ICA. Exposure of the proximal end of the aneurysm neck is mandatory for successful clipping. This is accomplished by extensive unroofing of the optic canal, removal of the anterior clinoid process, opening of the anterior part of the cavernous sinus, and exposure of the most proximal intradural (C2) and genu (C3) portions of the ICA. Four cases of giant aneurysms of the paraophthalmic ICA were successfully treated by this technique and the postoperative outcome was good in all cases. Preoperative magnetic resonance imaging for evaluation of the anatomical details, balloon occlusion test of the ICA, and intraoperative measurement of cortical blood flow were important to the success of the operation. Intraoperative digital subtraction angiography via the catheter placed in the cervical ICA was useful in confirming successful clipping.     

Transient renal dysfunction due to rhabdomyolysis after robot-assisted radical prostatectomy

International Urology and Nephrology - The aim of the present study was to investigate whether renal dysfunction following rhabdomyolysis occurs after robot-assisted radical prostatectomy (RARP),...