Involvement of the kisspeptin system in regulation of sexual behaviors in medaka

In mammals, kisspeptin (Kiss1) neurons are generally considered as a sex steroid-dependent key regulator of hypothalamic-pituitary-gonadal (HPG) axis. In contrast, previous studies in non-mammalian species, especially in teleosts, propose that Kiss1 is not directly involved in the HPG axis regulation, which suggests some sex-steroid-dependent functions of kisspeptin(s) other than the HPG axis regulation in non-mammals. Here, we used knockout (KO) medaka of kisspeptin receptor-coding genes (gpr54-1 and gpr54-2) and examined possible roles of kisspeptin in the regulation of sexual behaviors. We found that the KO pairs of gpr54-1, but not gpr54-2, spawned fewer eggs and exhibited delayed spawning than wild type pairs. Detailed behavior analysis suggested that the KO females are responsible for the delayed spawning and that the KO males showed hyper-motivation for courtship. Taken together, the present finding suggests that one of the reproductive-state-dependent functions of the Kiss1 may be the control of successful sexual behaviors.

Estrogen upregulates the firing activity of hypothalamic gonadotropin-releasing hormone (GnRH1) neurons in the evening in female medaka

The reproductive function of vertebrates is regulated by the hypothalamic-pituitary-gonadal axis. In sexually mature females, gonadotropin-releasing hormone (GnRH) neurons in the preoptic area (POA) are assumed to be responsible for a cyclic large increase in GnRH release, the GnRH surge, triggering a luteinizing hormone (LH) surge, which leads to ovulation. Precise temporal regulation of the preovulatory GnRH/LH surge is important for successful reproduction because ovulation should occur after follicular development. The time course of the circulating level of estrogen is correlated with the ovulatory cycle throughout vertebrates. However, the neural mechanisms underlying estrogen-induced preovulatory GnRH surge after folliculogenesis still remain unclear, especially in non-mammals. Here, we used a versatile non-mammalian model medaka for the analysis of the involvement of estrogen in the regulation of POA-GnRH (GnRH1) neurons. Electrophysiological analysis using a whole brain-pituitary in vitro preparation, which maintains the hypophysiotropic function of GnRH1 neurons intact, revealed that 17β-estradiol (E₂ ) administration recovers the ovariectomy-induced lowered GnRH1 neuronal activity in the evening, indicating the importance of E₂ for upregulation of GnRH1 neuronal activity. The importance of E₂ was also confirmed by the fact that GnRH1 neuronal activity was low in short-day photoperiod-conditioned females (low E₂ model). However, E₂ failed to upregulate the firing activity of GnRH1 neurons in the morning, suggesting the involvement of additional time-of-day signal(s) for triggering GnRH/LH surges at an appropriate timing. We also provide morphological evidence for the localization of estrogen receptor subtypes in GnRH1 neurons. In conclusion, we propose a working hypothesis in which both estrogenic and time-of-day signals act in concert to timely upregulate the firing activity of GnRH1 neurons that trigger the GnRH surge at an appropriate timing in a female-specific manner. This neuroendocrinological mechanism is suggested to be responsible for the generation of ovulatory cycles in female teleosts in general.

Neuropeptide B mediates female sexual receptivity in medaka fish, acting in a female-specific but reversible manner

Male and female animals display innate sex-specific mating behaviors. In teleost fish, altering the adult sex steroid milieu can effectively reverse sex-typical mating behaviors, suggesting remarkable sexual lability of their brains as adults. In the teleost medaka, neuropeptide B (NPB) is expressed female-specifically in the brain nuclei implicated in mating behavior. Here, we demonstrate that NPB is a direct mediator of estrogen action on female mating behavior, acting in a female-specific but reversible manner. Analysis of regulatory mechanisms revealed that the female-specific expression of NPB is dependent on direct transcriptional activation by estrogen via an estrogen-responsive element and is reversed in response to changes in the adult sex steroid milieu. Behavioral studies of NPB knockouts revealed that female-specific NBP mediates female receptivity to male courtship. The female-specific NPB signaling identified herein is presumably a critical element of the neural circuitry underlying sexual dimorphism and lability of mating behaviors in teleosts.

Sexually Dimorphic Neuropeptide B Neurons in Medaka Exhibit Activated Cellular Phenotypes Dependent on Estrogen

Brain and behavior of teleosts are highly sexually plastic throughout life, yet the underlying neural mechanisms are largely unknown. On examining brain morphology in the teleost medaka (Oryzias latipes), we identified distinctively large neurons in the magnocellular preoptic nucleus that occurred much more abundantly in females than in males. Examination of sex-reversed medaka showed that the sexually dimorphic abundance of these neurons is dependent on gonadal phenotype, but independent of sex chromosome complement. Most of these neurons in females, but none in males, produced neuropeptide B (Npb), whose expression is known to be estrogen-dependent and associated with female sexual receptivity. In phenotypic analysis, the female-specific Npb neurons had a large euchromatic nucleus with an abundant cytoplasm containing plentiful rough endoplasmic reticulum, exhibited increased overall transcriptional activity, and typically displayed a spontaneous regular firing pattern. These phenotypes, which are probably indicative of cellular activation, were attenuated by ovariectomy and restored by estrogen replacement. Furthermore, the population of Npb-expressing neurons emerged in adult males treated with estrogen, not through frequently occurring neurogenesis in the adult teleost brain, but through the activation of preexisting, quiescent male counterpart neurons. Collectively, our results demonstrate that the morphological, transcriptional, and electrophysiological phenotypes of sexually dimorphic preoptic Npb neurons are highly dependent on estrogen and can be switched between female and male patterns. These properties of the preoptic Npb neurons presumably underpin the neural mechanism for sexual differentiation and plasticity of brain and behavior in teleosts.

Evolutionally Conserved Function of Kisspeptin Neuronal System Is Nonreproductive Regulation as Revealed by Nonmammalian Study

The kisspeptin neuronal system, which consists of a neuropeptide kisspeptin and its receptor Gpr54, is considered in mammals a key factor of reproductive regulation, the so-called hypothalamic-pituitary-gonadal (HPG) axis. However, in nonmammalian vertebrates, especially in teleosts, existence of kisspeptin regulation on the HPG axis is still controversial. In this study, we applied multidisciplinary techniques to a teleost fish, medaka, and examined possible kisspeptin regulation on the HPG axis. First, we generated knockout medaka for kisspeptin-related genes and found that they show normal fertility, gonadal maturation, and expression of gonadotropins. Moreover, the firing activity of GnRH1 neurons recorded by the patch clamp technique was not altered by kisspeptin application. Furthermore, in goldfish, in vivo kisspeptin administration did not show any positive effect on HPG axis regulation. However, as kisspeptin genes are completely conserved among vertebrates except birds, we surmised that kisspeptin should have some important nonreproductive functions in vertebrates. Therefore, to discover novel functions of kisspeptin, we generated a gpr54-1:enhanced green fluorescent protein (EGFP) transgenic medaka, whose gpr54-1-expressing cells are specifically labeled by EGFP. Analysis of neuronal projection of gpr54-1:EGFP-expressing neurons showed that these neurons in the ventrolateral preoptic area project to the pituitary and are probably involved in endocrine regulation other than gonadotropin release. Furthermore, combination of deep sequencing, histological, and electrophysiological analyses revealed various novel neural systems that are under control of kisspeptin neurons-that is, those expressing neuropeptide Yb, cholecystokinin, isotocin, vasotocin, and neuropeptide B. Thus, our new strategy to genetically label receptor-expressing neurons gives insights into various kisspeptin-dependent neuronal systems that may be conserved in vertebrates.

Intravoxel Incoherent Motion in Normal Pituitary Gland: Initial Study with Turbo Spin-Echo Diffusion-Weighted Imaging

BACKGROUND AND PURPOSE

DWI with conventional single-shot EPI of the pituitary gland is hampered by strong susceptibility artifacts. Our purpose was to evaluate the feasibility of intravoxel incoherent motion assessment by using DWI based on TSE of the normal anterior pituitary lobe.

MATERIALS AND METHODS

The intravoxel incoherent motion parameters, including the true diffusion coefficient (D), the perfusion fraction (f), and the pseudo-diffusion coefficient (D*), were obtained with TSE-DWI in 5 brain regions (the pons, the WM and GM of the vermis, and the genu and splenium of the corpus callosum) in 8 healthy volunteers, and their agreement with those obtained with EPI-DWI was evaluated by using the intraclass correlation coefficient. The 3 intravoxel incoherent motion parameters in the anterior pituitary lobe were compared with those in the brain regions by using the Dunnett test.

RESULTS

The agreement between TSE-DWI and EPI-DWI was moderate (intraclass correlation coefficient = 0.571) for D, substantial (0.699) for f', but fair (0.405) for D*. D in the anterior pituitary lobe was significantly higher than in the 5 brain regions (P < .001). The f in the anterior pituitary lobe was significantly higher than in the 5 brain regions (P < .001), except for the vermian GM. The pituitary D* was not significantly different from that in the 5 brain regions.

CONCLUSIONS

Our results demonstrated the feasibility of intravoxel incoherent motion assessment of the normal anterior pituitary lobe by using TSE-DWI. High D and f values in the anterior pituitary lobe were thought to reflect its microstructural and perfusion characteristics.

Intraductal papillary mucinous tumors of the pancreas

Purpose: To compare the effectiveness of thin-section helical CT and MR imaging with gadolinium-enhanced dynamic technique and MR cholangiopancreatography (MRCP) in the examination of patients with intraductal papillary mucinous tumors.

Material and Methods: Helical CT, dynamic MR imaging, and MRCP of 25 intraductal papillary mucinous tumors were compared with ERCP and surgical findings.

Results: The duodenal papilla was identified by helical CT and dynamic MR imaging in 11 (44%) and 20 (80%) of the 25 patients, respectively ( p<0.05). The main pancreatic duct was visualized on helical CT, dynamic MR imaging, and MRCP in all patients (100%): 25 (96.2%), 24 (92.3%), and 26 (100%) cystic lesions were depicted, respectively. A communicating duct between the main pancreatic duct and the cystic lesion was visualized on helical CT, dynamic MR imaging, and MRCP in 14 (53.8%), 11 (42.3%), and 15 (55.7%) lesions, respectively. The papillary projections corresponding to 3 mm or larger papillary neoplasms were depicted on helical CT and MR imaging in 7 patients (25%).

Conclusion: MR imaging was equal or slightly superior to thin-section helical CT in the evaluation of intraductal papillary mucinous tumors.

Treatment of Hepatocellular Carcinoma by Intraarterial Injection of Adriamycin/Mitomycin C Oil Suspension (ADMOS) Alone or Combined with CIS-Diaminodichloroplatinum (CDDP)

We evaluated the effects of intraarterial injection of Adriamycin/Mitomycin C oil (Lipiodol) suspension (ADMOS) alone and ADMOS + cis-diaminodichloroplatinum (CDDP) in 135 patients with hepatocellular carcinoma (HCC). A total of 59 patients received ADMOS alone and 76 patients received ADMOS + CDDP (ADMOS/CDDP). Tumor size was reduced by over 25% in 13 (34%) of the evaluable 38 patients in the ADMOS-alone group and in 39 (51%) of the 76 evaluable patients in the ADMOS/CDDP group. Serum alpha-fetoprotein (AFP) levels decreased by more than 50% in 10 (59%) of 17 ADMOS-alone patients and in 23 (70%) of 33 ADMOS/CDDP patients whose pretreatment AFP levels were above 0.2 mg/l. The overall one- and 2-year survival rates were 68% and 41%, respectively. No severe complications and no significant changes in laboratory values were observed, except for one patient in the ADMOS/CDDP group who developed a liver abscess. Although the tumor response was significantly better in patients treated by ADMOS/CDDP than in those treated by ADMOS-alone (p < 0.05), there was no significant difference in the survival rates between the 2 groups. The intraarterial injection of ADMOS and CDDP was concluded to be effective in treating HCC judging by tumor response.

Distinguishing adrenal adenomas from non-adenomas on dynamic enhanced CT: a comparison of 5 and 10 min delays after intravenous contrast medium injection

AIM

To evaluate the usefulness of several parameters of 5 min compared to 10 min delayed contrast-enhanced CT in distinguishing adenomas from non-adenomas.

MATERIALS AND METHODS

The study population consisted of 94 patients (52 men and 42 women; mean age 62 years) with 103 adrenal lesions (75 adenomas and 28 non-adenomas). In each patient, unenhanced CT was followed by early, 5 and 10 min enhanced CT. Diagnostic parameters included delayed enhanced attenuation at 5 and 10 min, washout attenuation (WO) at 5 and 10 min, absolute percentage washout (APW) at 5 and 10 min, and relative percentage washout (RPW) at 5 and 10 min. The accuracy of each parameter for diagnosing adenomas from non-adenomas was calculated using receiver operating characteristic (ROC) analysis.

RESULTS

Upon comparison between 5 and 10 min delayed contrast-enhanced CT for differentiating total adenomas or lipid-poor adenomas from non-adenomas, there was no significant difference in the area under the binomial ROC curve (Az) values of delayed enhanced attenuation (total adenomas versus non-adenomas, p = 0.164; lipid-poor adenomas versus non-adenomas, p = 0.178), WO (total adenomas versus non-adenomas, p = 0.216; lipid-poor adenomas versus non-adenomas, p = 0.230), APW (total adenomas versus non-adenomas, p = 0.401; lipid-poor adenomas versus non-adenomas, p = 0.870), or RPW (total adenomas versus non-adenomas, p = 0.160; lipid-poor adenomas versus non-adenomas, p = 0.780).

CONCLUSION

Five minute contrast-enhanced CT was as useful as 10 min contrast-enhanced CT for differentiation of adrenal adenomas from non-adenomas.

Bone cement used as an embolic agent for active bleeding in vertebroplasty of metastatic lesions

We treated two cases of bleeding by injecting bone cement into tumor-feeding vessels of metastatic hypervascular tumors during a percutaneous vertebroplasty (PV) procedure. When the inner needle was pulled out after puncture of the metastatic vertebral tumor, active arterial bleeding from the outer needle cannula was noticed. Bleeding was not stopped by injection of Gelfoam particles through the cannula. Thus, bone cement was injected, which filled the tumor-feeding vessels, and bleeding stopped. Skin rash and high fever occurred 2-3 hours after the PV procedure, probably due to allergic reaction and massive tumor necrosis. To decrease the risk of active bleeding during PV for hypervascular bone metastases, arterial embolization of the feeding arteries should be performed 1 or 2 days prior to PV. If active bleeding occurs through the outer needle when performing PV, injection of bone cement after confirmation of bleeding from the tumor feeding vessels by vertebrography is effective.

Acceleration of primary liver tumor growth rate in embolized hepatic lobe after portal vein embolization

BACKGROUND

Portal vein embolization (PVE) is now widely accepted as a useful preoperative procedure in selected patients undergoing extended hepatectomy. However, the effect of PVE on the growth of liver tumors has not been fully elucidated.

PURPOSE

To retrospectively evaluate the effects of PVE on the growth of liver tumors in the embolized lobes.

MATERIAL AND METHODS

Eight patients with a primary liver tumor, six hepatocellular carcinomas (HCC) and two cholangiocellular carcinomas (CCC), were studied. The growth rates of the tumors in the embolized lobes and non-embolized liver parenchyma were calculated using the computed tomography (CT) volume values at the time of tumor identification, and before and after PVE.

RESULT

The median tumor growth rate was 0.59 cm(3)/day (range 0.22-6.01 cm(3)/day) before PVE and 2.37 cm(3)/day (range 0.29-13.97 cm(3)/day) after PVE (P = 0.018). The tumor growth acceleration ratios ranged from 1.50 to 7.46 (median 2.65) in the six HCCs, and were 1.00 and 1.32 in the two CCCs. There was no apparent correlation between the tumor growth rate after PVE and the growth rate of non-embolized liver parenchyma (median 6.00 cm(3)/day, range 1.24-11.0 cm(3)/day).

CONCLUSION

Liver tumor growth in an embolized lobe accelerates after PVE, in patients with HCC.

Superselective arterial embolization for patients with high-flow priapism: results of follow-up for five or more years

PURPOSE

To retrospectively evaluate the long-term results of transcatheter arterial embolization for high-flow priapism.

MATERIAL AND METHODS

The study comprised six patients with high-flow priapism treated by superselective embolization of the internal pudendal arteries at our institution. The cause of priapism was traumatic in five patients and idiopathic in one. Follow-up was > or = 5 years in all cases.

RESULTS

A total of nine embolizations were performed in the six patients. Embolization was performed once in three patients, while repeated embolizations were performed in the remaining three. Eleven arteries were altogether treated. Embolic materials used were gelatin sponge in nine arteries, gelatin sponge and microcoils in one, and microcoils alone in one. Embolization of the internal pudendal arteries on both sides in one single session was performed in one patient. In one patient, complete occlusion of the pseudoaneurysm was not achieved. However, restoration of erectile function and detumescence were noted during follow-up. Complications during the procedure were not registered. At follow-up > or = 5 years after successful embolization, all six patients experienced detumescence as well as normal erectile function.

CONCLUSION

Superselective embolization of the internal pudendal artery is the procedure of choice for treatment of high-flow priapism.

Early clinical signs and imaging findings in Gerstmann-Sträussler-Scheinker syndrome (Pro102Leu)

OBJECTIVE

To determine the clinical and radiologic features of Gerstmann-Sträussler-Scheinker syndrome caused by Pro102Leu mutation in PRNP (GSS102).

METHODS

The authors report 11 patients (nine families) with clinically and radiologically diagnosed GSS102.

RESULTS

All patients showed mild gait disturbance, dysesthesia and hyporeflexia of the lower legs, and truncal ataxia, and 9 of 11 patients showed proximal leg muscle weakness during the early stage of the disease. Dementia was not a main symptom during the early stage. Brain MRI and EEG abnormalities were not prominent initially. SPECT (N-isopropyl-p-[(123)I]iodoamphetamine) analyzed by the three-dimensional stereotactic surface projection (SSP) method detected abnormalities in five patients early during the course of the illness. SPECT findings showed diffusely decreased cerebral blood flow, demonstrated by a mosaic pattern, with the lowest perfusion noted in the occipital lobes. In contrast, blood flow to the cerebellum was preserved. These studies suggested sites of pathology in GSS102, with the main lesions probably located in the cerebrum and the spinal cord (posterior horn and spinocerebellar tract) instead of the cerebellum.

CONCLUSIONS

Key features for early diagnosis of Gerstmann-Sträussler-Scheinker syndrome caused by Pro102Leu mutation in PRNP (GSS102) are truncal ataxia, dysesthesia and hyporeflexia of the lower legs, and mild dysarthria. Normal cerebellar MRI and abnormal cerebral SPECT findings are characters of early GSS102.

Phase II study of conventional fractionated radiotherapy versus hyper-fractionated accelerated radiotherapy concomitant with low dose gemcitabine for patients with pancreatic cancer

14017

Background: Concurrent radiotherapy and chemotherapy with gemcitabine (GEM) has been reported to improve the median survival of patients with unresectable pancreatic cancer. Although hyperfractionated accelerated radiotherapy (HART) was administered to pancreatic cancer recently, the efficacy is unclear. Phase II study was conducted to evaluate the efficacy and the toxicity of HART concomitant with twice-weekly low dose GEM compared with conventionally fractionated radiotherapy (CRT) for unresectable pancreatic cancer. Methods: Between April 2001 and April 2004, 34 untreated eligible patients with histologically proven unresectable pancreatic cancer were enrolled. In CRT group (n=15), 50.4Gy was delivered in 28 fractions of 1.8Gy/day. In HART group (n=19), 50Gy was delivered in 40 fractions of 1.25Gy twice a day. All patients were treated with conformal radiation using 5mm multileaf collimeter. Concurrent chemotherapy with GEM (40mg/m2) was administered twice a week to both groups. Chemotherapy was suspended for Grade 3 toxicities or increase in temperature more than 38 °C. Response evaluations were conducted at six weeks after the treatment. Maintenance chemotherapy composed of GEM (1000mg/m2/week) for 3weeks was repeated every 4 weeks thereafter. Results: The median survival time (MST) was 11.3 months in CRT group and 12.9 months in HART group. The 1- and 2-year survival rates were 42.9% and 28.6% in CRT group, 52.9% and 17.6% in HART group. There was no significant difference in response rate between CRT and HART group (35.7% vs. HART; 35.3%). The median time to progression (TTP) was significantly prolonged in HART group (9.7months) compared with CRT group (5.9 months) (p=0.02). Overall treatment time was significantly shorter in HART group (37days) than CRT group (45days) (p=0.002). There was no significant deference in toxicity between CRT and HART group. Conclusions: HART concomitant with low dose GEM was well tolerated with acceptable toxicity and prolonged median TTP and MST with shortening of treatment time compared with conventional radio-chemotherapy. This regimen appears to be one of the crucial therapies for patients with unresectable pancreatic cancer.

No significant financial relationships to disclose.

Treatment of recurrent chordomas by percutaneous ethanol injection therapy and radiation therapy

We report a case of recurrent sacral chordomas that have been successfully controlled by the combination therapy of percutaneous ethanol injection therapy (PEIT) and radiation therapy in a 71-year-old man. PEIT may be one of the adjuvant therapies for recurrent chordomas.

Embolization of spontaneous rupture of an aneurysm of the ovarian artery supplying the uterus with fibroids

We report a case of spontaneous retroperitoneal hemorrhage caused by rupture of an aneurysm of the right ovarian artery in a 55-year-old woman. Diagnosis was achieved by computed tomography and arteriography. The ruptured aneurysm was treated by transcatheter arterial embolization using microcoils and gelatin sponge particles. This is the first case of rupture of an aneurysm of the ovarian artery not related to pregnancy, and the third case of embolization of a ruptured ovarian artery aneurysm in the literature. We illustrate the usefulness of embolization in treatment of an ovarian artery aneurysm without surgery.

Comparison of adrenal vein sampling value between aldosterone producing adrenal adenoma and non-functioning adrenal adenoma: evaluation using receiver operating characteristic analysis

PURPOSE

To evaluate adequate criteria for adrenal vein sampling values in patients with aldosterone producing adrenal adenoma (APA), retrospectively.

MATERIAL AND METHODS

Between 1988 and 2002, 59 hypertensive patients (15 M and 44 F, aged 47.58 +/- 9.45 years) were referred to our hospital and diagnosed with APA based on established criteria. During the same period, 23 patients with non-functioning adrenal adenoma (11 M and 12 F aged 53.56 +/- 11.76 years) were diagnosed based on computed tomography and laboratory data.

RESULTS

All 82 patients were enrolled in the present study. Bilateral adrenal vein sampling (AVS) for measurement of plasma aldosterone (A) and cortisol (C) was performed, and a receiver operating characteristics (ROC) analysis was conducted to establish the best criteria from the AVS-derived index in patients with APA. A (APA side)/A (contralateral side) was confirmed to provide the best diagnostic accuracy {(>2.5: right APA, sensitivity 83.3%, specificity 79.5%), (> 3: left APA, sensitivity 84.2%, specificity 76.9)}. The Az values for A (APA side)/A (contralateral side) were 0.8948 and 0.9260 for right and left APA, respectively.

CONCLUSION

The A (APA side)/A (contralateral side) value was the best compromise for sensitivity and false-positive rate for lateralization of APA.

Visualization of the internal mammary artery via the hepatic falciform artery in a patient with hepatocellular carcinoma

The hepatic falciform artery is a small vessel that arises as a terminal branch of the middle or left hepatic artery. Its anatomy and clinical importance have been described in several recent reports. During dissection of a cadaver, this artery is generally found connected with the ensiform branch of the internal mammary artery. However, to our knowledge, anastomosis has not previously been described radiologically.

Multidetector-row CT findings of colonic perforation: direct visualization of ruptured colonic wall

BACKGROUND

We examined the findings of contrast-enhanced multidetector-row computed tomography (MD-CT) in patients with colonic perforation.

METHODS

Abdominal contrast-enhanced MD-CT findings in six patients with colonic perforation were reviewed retrospectively. Patients (three men and three women) were 74 to 88 years old (mean age = 78 years). Colonic perforation was confirmed by surgery. CT findings were correlated with surgical and pathologic findings.

RESULT

The site of colonic perforation was suggested by the following combination of CT findings: free air, dirty mass, dirty fat sign, extraluminal fluid collection, bowel wall thickening, and interruption of colonic wall. The ruptured colonic wall was directly visualized in four cases (67%).

CONCLUSION

Abdominal contrast-enhanced MD-CT may improve the accuracy of diagnosis and localization of colonic perforation.

Long-term survivors of advanced esophageal cancer without surgical treatment: a multicenter questionnaire survey in Kyushu, Japan

Since the introduction of recent improvements in adjuvant therapy for esophageal cancer, some patients have demonstrated good prognosis. In the present study, we analyzed 3- and 5-year survivors of advanced esophageal cancer who did not undergo any surgical treatment. Between 1990 and 1998, 831 patients were admitted to 14 university hospitals and one cancer center associated with the membership of the Kyushu study group for adjuvant therapy of esophageal cancer. Twelve (1.4%) of the patients were 3-year survivors and 13 (1.6%) were 5-year survivors. The reasons for non-operation were refusal (eight patients), tumor-related factors (11 patients), and host-related factors (six patients). With a single exception, all patients had locally advanced tumors. Almost all long-term survivors had fewer than five lymph node metastases, in regions limited to the neck and/or mediastinum. Radiation therapy was combined with chemotherapy for 16 of the 25 patients, and chemotherapy-based cisplatin was used for 15 of these 16 patients. Fifteen of the patients remain alive; 10 died seven of them from esophageal cancer. Chemoradiation therapy was effective for some patients with locally advanced esophageal cancer, particularly in the absence of or with few lymph node metastases. To improve the prognosis of patients with advanced esophageal cancer who, for various causes, cannot undergo surgical treatment, a new protocol for adjuvant therapy is required.

Intraductal papillary mucinous tumors of the pancreas. Comparison of helical CT and MR imaging

PURPOSE

To compare the effectiveness of thin-section helical CT and MR imaging with gadolinium-enhanced dynamic technique and MR cholangiopancreatography (MRCP) in the examination of patients with intraductal papillary mucinous tumors.

MATERIAL AND METHODS

Helical CT, dynamic MR imaging, and MRCP of 25 intraductal papillary mucinous tumors were compared with ERCP and surgical findings.

RESULTS

The duodenal papilla was identified by helical CT and dynamic MR imaging in 11 (44%) and 20 (80%) of the 25 patients, respectively (p<0.05). The main pancreatic duct was visualized on helical CT, dynamic MR imaging, and MRCP in all patients (100%): 25 (96.2%), 24 (92.3%), and 26 (100%) cystic lesions were depicted, respectively. A communicating duct between the main pancreatic duct and the cystic lesion was visualized on helical CT, dynamic MR imaging, and MRCP in 14 (53.8%), 11 (42.3%), and 15 (55.7%) lesions, respectively. The papillary projections corresponding to 3 mm or larger papillary neoplasms were depicted on helical CT and MR imaging in 7 patients (25%).

CONCLUSION

MR imaging was equal or slightly superior to thin-section helical CT in the evaluation of intraductal papillary mucinous tumors.

Left renal vein aneurysm: imaging findings

A renal vein aneurysm is a rare vascular disease. To our knowledge, only six cases have been reported. We describe a 57-year-old woman with a left renal vein aneurysm diagnosed by a combination of ultrasonography, color Doppler ultrasonography, contrast-enhanced computed tomography, and magnetic resonance imaging.

Bone and Tl-201 scintigraphy in a case of hereditary multiple exostoses

A 17-year-old girl with hereditary multiple exostoses, who was thought to have malignant transformation of an exostotic lesion, was examined by bone and Tl-201 chloride scintigraphy. Scintigraphy showed markedly intense uptake by the lesion, whereas Tl-201 imaging did not. Bone scintigraphy revealed intense to moderate uptake in other exostotic lesions, but none was apparent on the Tl-201 study. The lesion was resected and the histopathologic diagnosis was osteochondroma. Negative findings of Tl-201 scintigraphy may not exclude the possibility of chondrosarcoma, and the utility of this method may be limited. However, Tl-201 scintigraphy appears to have a useful role in differentiating malignant transformation from benign osteochondroma in hereditary multiple exostoses.

[A study on the isolation period of patients with metastatic thyroid cancer treated by 131I according to a new guideline]

In Japan, a new guideline for the release of patients administered 131I was issued by the Ministry of Welfare on June, 1998: The dose rate is under 30 microSv/h at 1 m or the activity in the body is under 500 MBq. This study was designed to set the appropriate isolation period enough to satisfy these limits. A total of 28 patients with the history of total thyroidectomy and metastasis were selected for this study. In these patients, 28 patients were treated with oral administration of 3.7 GBq of Na131I (72 times), and one of 28 patients was once treated with 5.55 GBq of Na131I. Two of them were also received a total of 4 courses of a split dose therapy of 3.7 GBq of Na131I (740 MBq once a week for 5 consecutive weeks = one course). Measurements of the external exposure dose (microSv/h) at 1 m and the urinary excretory radioactivity (MBq) were performed at various times. There was a good correlation of the external exposure dose between standing (x microSv/h) and sitting (y microSv/h) postures (y = 0.99x + 0.406, r = 0.99, p < 0.0001, n = 169). The difference in the external exposure dose before and after urination (x microSv/h) had a significant correlation with the urinary excretory radioactivity (y MBq); y = 16.6x + 24.8, r = 0.96, p < 0.001, n = 41. Also, there was a significant correlation between the predicted value of residual radioactivity in the body (y' MBq) and the external exposure dose (x' microSv/h); y' = 20.8x' + 31.5, r = 0.98, p < 0.001, n = 77. In the patients treated with 3.7 GBq of Na131I, the mean and S.D. values of the external exposure dose (microSv/h) changed as follow: After 6 hr, 168 +/- 40; 24 hr, 52 +/- 23; 48 hr, 20 +/- 15; 72 hr, 10 +/- 9; and 96 hr, 8 +/- 9. The percentages of the patients satisfied the new guideline were as follow; 21.7% at 24 hr, 81.2% at 48 hr and 100% after 72 hr. Therefore the 3-day isolation is sufficient for the patients administered 3.7 GBq of Na131I.

Pericaval fat mimicking intracaval deposits on unenhanced and contrast-enhanced helical CT in patients with cirrhosis

PURPOSE

The purpose of this work was to determine whether there is a significant difference in radiographic depiction of pericaval fat mimicking intracaval deposits on CT scans in patients with cirrhosis versus those without cirrhosis.

METHOD

The incidence of radiographic pseudolesions depicted as an intracaval fat mass identified on CT scans in 62 patients with cirrhosis was compared with that in 81 patients without cirrhosis.

RESULTS

Pericaval fat depicted as an intracaval fat mass was identified more frequently in patients with cirrhosis (20/62, 32%) than in patients without cirrhosis (4/81, 5%), representing a statistically significant difference (p < 0.0001). A total of 24 lesions were seen in 20 patients with cirrhosis. Lesions were identified at the confluence of the hepatic veins (n = 19), below the confluence (n = 4), and above the confluence (n = 1). Pseudolesions appeared round (n = 5), oval (n = 15), or linear (n = 4). Locations included medial (n = 15), posteromedial (n = 4), anteromedial (n = 1), and posterior (n = 4). The average length was 1.5 cm.

CONCLUSION

The cause of pseudolesions depicted as intracaval fat masses on CT is likely secondary to morphologic changes in the liver such as cirrhosis.

Decreased perfusion of the bilateral thalami in patients with chronic pain detected by Tc-99m-ECD SPECT with statistical parametric mapping

The purpose of this study was to examine whether the Tc-99m-ECD SPECT can detect any difference between the brain perfusion in patients with chronic pain and normal controls by means of the Statistical Parametric Mapping (SPM96). The subjects were twelve patients with chronic pain (CP group) and twelve normal controls (NC group). After informed consent was obtained, 720 MBq of Tc-99m-ECD was intravenously injected as a bolus. The SPECT data were acquired once for 20 mins from 5 mins after i.v. injection of Tc-99m-ECD, with a triple-head rotating gamma camera. The SPECT data were transformed into a standard stereotactic space, and group comparisons between CP and NC groups were performed on a voxel-by-voxel basis. The subset of voxels exceeding a threshold of p < 0.001 in omnibus comparisons and remaining significant after correction for multiple comparison (p < 0.05) was displayed as a volume image rendered in three orthogonal projections. There was a significant decrease in perfusion in the bilateral thalami in the CP group, suggesting that perfusion in the thalamus generally decreases in patients with chronic pain. Tc-99m-ECD SPECT with SPM96 may be useful for studies of the mechanisms of chronic pain.

Correlations between colonic wall thickening in patients with virally induced cirrhosis on CT and clinical status

PURPOSE

The purpose of this work was to determine the frequency and CT imaging spectrum of colonic wall thickening and correlate these with the clinical severity of virally induced cirrhosis.

METHOD

Fifty-nine patients were identified with virally induced cirrhosis and no other causes of colonic wall thickening. The abdominal CT scans of these patients were retrospectively reviewed by two radiologists to determine the presence of colonic wall thickening from the ascending colon to the descending colon, to assess the segmental distribution, and to correlate these findings with the clinical status assessed by Child-Pugh classification, presence of ascites, splenic volume index, varices score, and serum albumin levels.

RESULTS

Colonic wall thickening was identified in 18 (31%) patients. The frequency of the affected distribution of colonic wall thickening was as follows: ascending colon in 17 (29%) patients, transverse colon in 11 (19%) patients, and descending colon in 7 patients (12%). The ascending colon was the most common site of colonic wall thickening (p < 0.001). Ten (17%) patients had multisegmental distributions. Colonic wall thickening had a statistically significant association with Child-Pugh grades A, B, and C (p < 0.0001), presence of ascites (p < 0.0004), splenic volume index (p = 0.0026), varices score (p < 0.0001), and serum albumin levels (p = 0.0364). The segmental distribution of wall thickening significantly correlated with Child-Pugh grades A, B, and C (p = 0.0005), presence of ascites (p < 0.001), varices score (p < 0.0001), serum albumin levels (p < 0.0001), and splenic volume index (p = 0.0135).

CONCLUSION

Colonic wall thickening occurs commonly in patients with virally induced cirrhosis. The presence and number of colonic wall thickening were correlated with the grading of the severity of cirrhosis.

Progressing features of atypical mycobacterial infection in the lung on conventional and high resolution CT (HRCT) images

PURPOSE

The aim of this study was to clarify the localization of abnormalities within secondary pulmonary lobules and the changes in follow-up studies of pulmonary atypical mycobacterial infection (AMI) by conventional and high-resolution computed tomography (HRCT).

MATERIALS AND METHODS

Forty-six patients (16 men and 30 women; 43-84 years) with pulmonary AMI (M. intracellulare 36; M. avium 10) in the lung were examined by conventional and HRCT.

RESULTS

In peripheral zones, all patients had the nodule located in the terminal or lobular bronchiole, and most of the patients also had nodules accompanied with a wedge-shaped or linear shadow connected with the pleura. In the follow-up scans, new centrilobular nodules appeared in other segments, and consolidation or ground-glass pattern appeared newly and was preceded by nodules. Bronchiectasis became more severe in five of 38 follow-up patients.

CONCLUSION

The common HRCT findings of AMI were centrilobular, peribronchovascular nodules, bronchiectasis, consolidation, and pleural thickening/adhesion. The nodules frequently connected with the pleura. The initial and follow-up studies suggest that the disease may begin in the terminal bronchiole or as preexisting bronchiectasis and spread transbronchially along the draining bronchus or towards the pleura to produce lesions such as new nodules, cavities, consolidation, pleuritis, and bronchiectasis, or more severe bronchiectasis.

Pain palliation by percutaneous acetabular osteoplasty for metastatic hepatocellular carcinoma

A 68-year-old man with hepatocellular carcinoma and known skeletal metastasis developed right hip pain and gait disturbance due to an osteolytic metastasis in the right acetabulum. This was treated initially with chemoembolization and radiation therapy. When these procedures proved unsuccessful percutaneous injection of acrylic bone cement into the acetabulum was undertaken. Immediately after this procedure, he obtained sufficient pain relief and improved walking ability, which continued for 3 months until he died of hepatic insufficiency.

Aberrant brain activation following motor skill learning in schizophrenic patients as shown by functional magnetic resonance imaging

BACKGROUND

Motor skill learning may be impaired in schizophrenia. While functional brain imaging studies have shown reduced activation during motor task performance in schizophrenic patients, brain activity changes with motor skill learning in these patients have not been studied by functional imaging.

METHODS

A sequential complex motor task involving the right hand was performed by nine medicated schizophrenic patients and 10 age-matched healthy controls. Functional magnetic resonance images were obtained using a gradient echo, echoplanar imaging (EPI) pulse sequence before and after 1 week of training in performing the task.

RESULTS

Bilaterally, patients showed significantly less blood oxygenation level-dependent (BOLD) signal response in the premotor area (PMA) before beginning motor training than controls. BOLD signal response increased in the left PMA of schizophrenic patients after 1 week of motor training; in contrast, the signal decreased in the left PMA of control subjects. Training effects concerning the number of finger movement sequences achieved did not differ between groups. Daily neuroleptic dose did not significantly affect changes with training in BOLD signal response in the PMA.

CONCLUSIONS

These preliminary results suggest that schizophrenic patients have dysfunction of neural networks in areas including the PMA that are involved in executing a complex motor task. In terms of brain activity, motor learning may be less efficient or slower in the patients than in healthy subjects.

Focal fatty infiltration in the posterior aspect of hepatic segment IV: relationship to pancreaticoduodenal venous drainage

OBJECTIVE

We aimed to investigate the relationship between fatty infiltration in the posterior aspect of hepatic segment IV and pancreaticoduodenal venous drainage.

METHODS

Pancreaticoduodenal arteriography was performed in 21 patients who had nontumorous portal perfusion defects in the posterior aspect of hepatic segment IV, as demonstrated on CT during arterial portography (CTAP).

RESULTS

In 10 patients, pancreaticoduodenal arteriography showed an aberrant nonportal vessel with flow toward the hepatic hilum in the venous phase. Four of the 10 patients with nonportal vessels from the pancreaticoduodenal arterial system had fatty infiltration in segment IV. In three of these four patients, the fatty infiltration was focal and localized to that area. On the other hand, none of the 11 patients without nonportal vessels from the pancreaticoduodenal arterial system had fatty infiltration in the regions corresponding to the nontumorous portal perfusion defects on CTAP. Moreover, three patients with diffuse fatty liver had a focal nonfatty area in segment IV.

CONCLUSIONS

Focal fatty infiltration in the posterior aspect of hepatic segment IV seems to be related to pancreaticoduodenal venous drainage.

[Nuclear medicine for general radiologists: endocrinological examinations]

We reviewed nuclear endocrinological examinations of the thyroid, parathyroid, and adrenal glands that are clinically performed in Japan as well as somatostatin receptor imaging, which is widely used in Europe, the United States, and other countries. 123I thyroid scintigraphy is especially useful in detecting ectopic goiters and differentiating between Basedow's disease and subacute thyroiditis or Plummer's disease, all of which exhibit thyrotoxicosis. 201Tl is useful to detect foci metastasized from well differentiated thyroid cancer and to differentiate malignant from benign tumors. 67Ga-citrate is an agent used for patients suspected of having malignant lymphoma or undifferentiated carcinoma of the thyroid. Radioiodinated MIBG is a specific agent for medullary thyroid carcinoma. 99mTc-MIBI is a good agent for locating hyperfunctioning parathyroid tissues. 131I-adosterol is useful to locate the lesions of primary aldosteronism, Cushing's syndrome, adrenogenital syndrome, and select adenomas among incidental tumors. Radioiodinated MIBG scintigraphy has high diagnostic accuracy in locating pheochromocytomas and neuroblastomas. 111In-labeled octreotide is useful in locating, hormone-producing gastrointestinal and pancreatic tumors including carcinoids, gastrinomas, and insulinomas. Radiolabeled somatostatin receptor analogs are used not only to locate but also to treat malignant somatostatin receptor-positive tumors. We hope that Octreoscan will be available in Japan in the near future.

Characteristic regional cerebral blood flow patterns in anorexia nervosa patients with binge/purge behavior

OBJECTIVE

The authors' goal was to investigate the effect of imagining food on the regional cerebral blood flow (rCBF) of anorexia nervosa patients with and without habitual binge/purge behavior.

METHOD

The subjects included seven female patients with purely restrictive anorexia, seven female patients with anorexia and habitual binge/purge behavior, and seven healthy women. Single photon emission computed tomography examination was performed before and after the subjects were asked to imagine food. Changes in rCBF count ratios (percent change) were then calculated and compared. The subjects were also asked to assess their degree of fear regarding their control of food intake.

RESULTS

The anorexia nervosa patients with habitual binge/purge behavior had a significantly higher percent change in the inferior, superior, prefrontal, and parietal regions of the right brain than the patients with purely restrictive anorexia and the healthy volunteers. The patients with habitual binge/purge behavior also had the highest level of apprehension in regard to food intake.

CONCLUSIONS

Specific activation in cortical regions suggests an association between habitual binge/purge behavior and the food recognition process linked to anxiety in patients with anorexia nervosa.

Cholangiolocellular carcinoma of the liver: CT and MR findings

The authors report two cases of surgically proved cholangiolocellular carcinoma of the liver. Marked contrast enhancement was observed at the periphery of the tumor on CTs and MRIs obtained during the hepatic arterial and portal venous phases, with concentric filling on the delayed images. On T1-weighted and T2-weighted MRIs, the tumor was, respectively, hypointense and hyperintense, with a central hypointense area. Therefore, helical CT and MRI features of these cholangiolocellular carcinomas were thought to be similar to those of cholangiocarcinoma.

Intrahepatic portal venous variations: demonstration by helical CT during arterial portography

PURPOSE

We assessed the prevalence and types of intrahepatic portal venous variations by helical computed tomography performed with arterial portography (CTAP).

METHODS

In 192 patients without evidence of vascular invasion or distortion, CTAP images were reviewed retrospectively to identify portal venous variations.

RESULTS

Of the 192 patients examined, 10 (5.2%) had trifurcation, 5 (2.6%) had a right posterior segmental branch arising from the main portal vein, 5 (2.6%) had an absence of the horizontal segment of the left portal vein, and 1 (0.5%) had an absence of the left lateral segmental portal branch. Of the patients without a horizontal segment, two had a right-sided ligamentum teres associated with malposition of the gallbladder, while another had complete ramification of intrahepatic portal branches from an umbilical vein-like segment. In the patient missing the left lateral segmental branches, the right portal vein segments were subcapsularly located.

CONCLUSION

Variations of the intrahepatic portal veins can be recognized on CTAP imaging. tomography-Portal vein, computed tomography.

Hepatic falciform artery. Angiographic findings in 25 patients

PURPOSE

To determine the frequency of hepatic falciform artery (HFA) occurrence on celiac or hepatic angiograms and elucidate the anatomy and clinical importance.

MATERIAL AND METHODS

Among 1,250 patients who underwent celiac or hepatic arteriography, we encountered 25 patients (2%) with a HFA. Prospectively, CT hepatic falciform arteriography (CTHA) was performed in 4 patients. Indigocarmine dye was injected into the HFA in 6 patients to evaluate whether the abdominal skin was stained. Embolization of the HFA before chemoembolization for hepatocellular carcinoma was performed in 4 patients to prevent abdominal wall injury.

RESULTS

Among 25 patients, the HFA arose as a terminal branch of the middle hepatic artery in 14 patients (56%) and of the left hepatic artery in 11 patients (44%). The vessel was single in 18 patients (72%) and double in 7 patients (28%). Two vessels ran side by side along the hepatic falciform ligament. On CTHA, the HFA ran within the hepatic falciform ligament and the branches were connected with the liver around the hepatic falciform ligament. After indigocarmine dye injection, the stain of abdominal skin was recognized in all 6 patients. No abdominal wall injury occurred in any of the 4 patients who were subjected to hepatic chemoembolization.

CONCLUSION

HFA is an extrahepatic pathway which runs to the abdominal wall. Before chemoembolization of the middle or left hepatic artery for hepatic malignancy, the HFA should be recognized.