Impaired respiratory mechanics in pulmonary emphysema: evaluation with dynamic breathing MRI

To evaluate impaired respiratory mechanics in pulmonary emphysema, dynamic breathing magnetic resonance imaging (BMRI) was acquired with fast-gradient echo pulse sequences at fixed thoracic planes over two to three slow, deep respiratory cycles in 6 controls and 28 patients with pulmonary emphysema including 9 patients undergoing lung volume reduction surgery (LVRS). Respiratory motions of the diaphragm and chest wall (D/CW) were assessed by a cine-loop view, a fusion display of maximal inspiratory and expiratory images, and the time-distance curves. By contrast with normal subjects with regular synchronous D/CW motions, the patients frequently showed reduced, irregular, or asynchronous motions, with significant decreases in the maximal amplitude of D/CW motions (MAD and MACW), and the length of apposition of the diaphragm (LAD) (P < 0.0001, P < 0.001, P < 0. 01, respectively). After LVRS, nine patients showed improvements in D/CW configuration and mobility, with significantly increased MAD, MACW, and LAD (P < 0.01, P < 0.0001, and P < 0.05, respectively). In 40 studies of 28 patients including the post-LVRS examinations, the normalized MAD and MACW significantly correlated with %FEV(1) (r = 0. 881 and r = 0.906; P < 0.0001, respectively). BMRI seems useful for noninvasively and directly assessing the impaired respiratory mechanics associated with abnormal ventilation in pulmonary emphysema, and also for monitoring the effects of LVRS. J. Magn. Reson. Imaging 1999;10:510-520.

Neurotransmitters and neuromodulators involved in laryngeal innervation

The distribution and role of neurotransmitters and neuromodulators in laryngeal innervation are reviewed, and our recent findings regarding the nitrergic innervation of the larynx are demonstrated for the better understanding of the complexity of the laryngeal innervation system. Noradrenergic innervation of the larynx was studied with fluorescence histochemistry and electron microscopy after application of 5-hydroxydopamine. These studies confirmed the existence of noradrenergic innervation for the submucosal glands and blood vessels, and the origin and course of noradrenergic nerve fibers contained in the laryngeal nerves and their destinations in the larynx. Cholinergic innervation of the larynx has not been clarified in detail. Many kinds of neuropeptides have been demonstrated to be involved in laryngeal innervation. Vasoactive intestinal polypeptide originating from intralaryngeal ganglionic neurons participates in laryngeal vasodilation and reduction of laryngeal seromucous secretion. Neuropeptide Y nerve fibers are few in the larynx, and most originate from the superior cervical ganglion. They are distributed around the large or medium-sized blood vessels, especially arteries. They are also associated with excretory structures. Substance P was the first neuropeptide found to be a sensory neurotransmitter in the laryngeal afferent system. It is also involved in regulation of laryngeal blood flow and secretion. Calcitonin gene-related peptide is associated with the sensory, autonomic, and motor innervation of the larynx. The majority of enkephalin nerve fibers are located close to excretory structures, although no information on the physiological significance of enkephalin is available. In addition to the above neuropeptides, the peptides histidine isoleucine, histidine methionine, and helospectin have been shown to exist in the larynx. The nitrergic innervation of the larynx has been recently studied with NADPH-diaphorase histochemistry and immunohistochemistry using antiserum against nitric oxide synthase. Nitric oxide originates from the neurons in the intralaryngeal ganglia and is believed to modulate blood flow and secretion of the larynx. It controls the laryngeal exocrine secretion in cooperation with intrinsic vasoactive intestinal polypeptide and/or extrinsic calcitonin gene-related peptide. Nitric oxide from the nodose ganglion may modulate nociception of the larynx. The existence of nitrergic neurons located in the intrinsic laryngeal muscles has been demonstrated. Many of them are bipolar or pseudounipolar, so they might be sensory in nature. The effect of injury of the recurrent laryngeal nerve on the induction of nitric oxide synthase in the laryngeal motoneurons is also discussed.

Effective treatment with chemotherapy and surgical resection for small cell carcinoma of the esophagus: report of a case

We report on a patient with small cell carcinoma of the esophagus treated with effective combination chemotherapy followed by surgical resection. A 69 year-old male had an ulcerated tumor in the middle part of the esophagus, which was microscopically diagnosed as small cell carcinoma of the esophagus. After combination chemotherapy, endoscopy showed that the esophageal tumor had changed into a shallow ulcer. No cancer cell was found in the biopsy specimen of the ulcer. A subtotal esophagectomy with regional lymph node dissection was performed. Histological examination showed that a few cancer cells remained in a microvessel of the submucosal layer in the removed esophagus and no cancerous lesion was found in regional lymph nodes. The patient was well and was able to remain at home. However, he eventually died 21 months after first detection of the carcinoma due to progression of multiple lung and mediastinal lymph node metastases. After complete or partial remission is achieved by the combination chemotherapy, surgical resection may be recommended as the second therapy that occasionally produces long-term remission and possibly long-term survival for patients with small cell carcinoma of the esophagus, such as the present case.

Idiopathic saccular aneurysm of the azygos vein

Idiopathic saccular aneurysm of the azygos vein is a rare condition. We report the case of a 52-year-old man with saccular aneurysm of the azygos vein who underwent surgical resection. Preoperative dynamic computed tomography revealed strong and rapid enhancement of the chest mass. Magnetic resonance imaging showed a thoracic tumor with low signal intensity on the T1-weighted image and coexistence of low and high signal intensity on the T2-weighted image. Intraoperative findings showed cystic dilatation of the azygos vein. Although an accurate preoperative diagnosis of saccular azygos vein aneurysm is difficult, especially differential diagnosis between this anomaly and mediastinal tumors, a markedly enhanced mass shown by dynamic computed tomography was useful for the preoperative diagnosis of this anomaly.

Immunoblastic lymphadenopathy-like T-cell lymphoma complicated by multiple gastrointestinal involvement

We report a rare case of immunoblastic lymphadenopathy (IBL)-like T-cell lymphoma complicated by multiple gastrointestinal involvement, which appeared to be ameliorated by chemotherapy but resulted in perforative peritonitis. A 66-year-old Japanese woman who had generalized lymphadenopathy and eruptions was admitted to our hospital because of bloody stool. Colonoscopic examination revealed hemorrhagic ulcers in the terminal ileum and a saucer-like ulcer in the cecum. Gastrointestinal endoscopy revealed several ulcerative or elevated lesions in stomach and duodenum. Biopsy specimens of these lesions and of a lymph node showed characteristic histological features of IBL-like T-cell lymphoma. The initial treatment with prednisolone (PSL) and cyclophosphamide (CPA) was effective. Six months after the treatment, however, she developed bloody stool again caused by multiple ulcerative lesions in the large intestine. The recurrence of the disease was determined histologically, and four courses of CPA, PSL, vinblastine sulfate and doxorubicin hydrochloride (CHOP) therapy were administered. One month after completing the CHOP therapy, she developed intestinal obstruction and then acute peritonitis resulting from perforation at an ulcer scar in the jejunum. Surgical treatment was successful, and histological examination demonstrated no lymphoma cells in the resected specimen. A gastrointestinal perforation should be recognized as a potential complication of IBL-like T-cell lymphoma, even during remission.

Accelerated reoxygenation of a murine fibrosarcoma after carbon-ion radiation

PURPOSE

Reoxygenation of a murine tumour after irradiation with carbon ions was investigated and compared to that after gamma-rays.

MATERIALS AND METHODS

NFSa fibrosarcoma cells were transplanted into the right hind legs of syngeneic C3H male mice. Conditioning irradiation with either 290 MeV/u carbon ions or 137-Cs gamma-rays was delivered to the tumours at 8 mm diameter. At given times after irradiation the leg tumours, either clamped or not, received test doses of photons. Differences in tumour growth delay between the clamped and non-clamped tumours were interpreted in terms of reoxygenation. A lung-colony assay was used to obtain cell-survival curves.

RESULTS

The oxygen enhancement ratio in the NFSa tumour for 74 keV microm(-1) carbon ions was 1.6 while that for gamma-rays was 3.4. The NFSa tumours reoxygenated 4 days after 30 Gy of gamma-ray irradiation, but reoxygenated as early as 1 day after 16 Gy of carbon ions. Reoxygenation after gamma-rays shortened to 1 day when the tumours were initially clamped for the conditioning irradiation.

CONCLUSIONS

The fraction of surviving oxic cells in the NFSa tumours is larger after irradiation with carbon ions than with gamma-rays, resulting in accelerated reoxygenation.

Nitric oxide synthase and NADPH-diaphorase in neurons of the rat, dog and guinea pig nodose ganglia

Localization of nitric oxide synthase (NOS) in the nodose ganglia of the dog, rat and guinea pig was investigated. A double-staining technique of NOS immunohistochemistry and NADPH-diaphorase (NADPHd) histochemistry was used; then the ratio of NADPHd-positive and NOS-positive cells to the total cells was calculated. The distribution of positive cells within the canine nodose ganglion was also investigated. NADPHd-positive neurons were detected in all the ganglia. Three intensities of reactivity to NADPHd histochemistry (strong, weak or negative) were detected in the neurons of all three species. There were more cells that stained strongly for NADPHd in the rat, but fewer in the dog and guinea pig, indicating that a species difference may exist. NADPHd-positive neurons were less abundant in the rostral third of the canine nodose ganglion than in the middle or caudal thirds. NADPHd reactivity was completely co-localized to the cells that demonstrated neuronal NOS immunoreactivity in the canine nodose ganglion. Thus, NADPHd histochemical reactivity may be a reliable marker of NOS in the nodose ganglion.

Neurochemical substances in neurons of the canine intrinsic laryngeal muscles

The localization of vasoactive intestinal polypeptide (VIP), calcitonin gene-related peptide (CGRP), catecholamines (CA) and carbon monoxide (CO) in neurons of the intrinsic laryngeal muscles of the dog was investigated using immunohistochemistry. Cells with VIP-like immunoreactivity were found between the striated muscle fibres of the cricothyroid and posterior cricoarytenoid muscles, some aggregated into a ganglion and some solitary. Neurons with immunoreactivity to haem oxygenase-2 (HO-2), an immunohistochemical marker for CO, were also seen. VIP-or HO-2-negative cells also existed in various numbers in the intramuscular ganglia. No CGRP-like immunoreactive neurons were found although CGRP-like immunoreactive varicose fibres were seen in the intramuscular ganglia. No neurons or fibres immunoreactive to tyrosine hydroxylase (TH), the key enzyme in synthesis of CA, were detected. The exact function of these intramuscular ganglia is yet to be clarified, but they may be sensory neurons.

Diagnostic pitfalls of MR cholangiopancreatography in the evaluation of the biliary tract and gallbladder

Magnetic resonance (MR) cholangiopancreatography is a noninvasive imaging technique that has proved accurate in the diagnosis of biliary obstruction. However, various diagnostic pitfalls have been reported with MR cholangiopancreatography that were not encountered previously at conventional biliary imaging. These pitfalls may simulate or mask various pathologic conditions of the extrahepatic bile duct or main pancreatic duct and may be caused by a variety of factors. Because of its postprocessing nature, maximum-intensity-projection reconstruction may mask a small gallstone if the stone is surrounded by hyperintense bile and may cause false ductal disconnection or duplication when a breath hold is not performed perfectly. Extraductal factors (e.g., metallic surgical clips, intravascular metallic coils, gas in the stomach or duodenum) can cause signal loss in the adjacent part of the extrahepatic bile duct, which may in turn lead to a false-positive diagnosis of ductal narrowing or obstruction. Normal vascular structures including the right hepatic and gastroduodenal arteries can cause pseudo-obstruction of the extrahepatic bile duct by pulsatile compression. Intraductal factors (e.g., gas, hemorrhage, debris, iodinated contrast material) reduce the signal intensity of the bile, which may result in pseudo-obstruction, false filling defects, or a nonvisualized gallbladder or bile duct. Knowledge of the existence and high prevalence of these diagnostic pitfalls should help prevent misinterpretation of MR cholangiopancreatograms.

Using helical CT to evaluate renal cell carcinoma in patients undergoing hemodialysis: value of early enhanced images

OBJECTIVE

The purpose of this study was to evaluate early and delayed enhanced helical CT for revealing renal cell carcinoma in patients undergoing hemodialysis.

MATERIALS AND METHODS

Over the course of 3 years, 630 chronic hemodialysis patients underwent early and delayed contrast-enhanced and unenhanced helical CT to detect renal cell carcinoma. Retrospective review showed that 23 of these patients later underwent either unilateral or bilateral nephrectomy. Two radiologists, unaware of the pathology results, independently reviewed these 23 examinations. The sensitivity and specificity of each early and delayed scan for revealing neoplasms were determined using pathology as the gold standard. The mean attenuation values of the neoplasms and parenchymas of end-stage kidneys on both early and delayed enhanced images were also compared.

RESULTS

Helical CT revealed 225 lesions, 24 of which were found to be renal cell carcinomas at pathology. Delayed enhanced helical CT failed to detect one papillary carcinoma in an end-stage kidney with acquired cysts. Three nonpapillary carcinomas were not detected on delayed scans, and one was missed on an early scan of a patient without acquired cysts. The sensitivity and specificity of early enhanced CT for revealing renal cell carcinoma were 96% and 95%, respectively. In contrast, delayed enhanced CT achieved a sensitivity of 83% and a specificity of 94%. A significant difference in mean attenuation values between carcinomas and renal parenchymas was observed on the images with early enhancement but not on those with delayed enhancement (p < .0001).

CONCLUSION

Early enhanced helical CT is superior to delayed enhanced helical CT for revealing renal cell carcinoma in end-stage kidneys.

[Leiomyoma of the lung: a case report]

An asymptomatic 43-year-old female was admitted to the Hospital because of an abnormal nodule in the left lung field on screening chest X-ray. Chest CT showed a tumor shadow mass (4 x 3 cm) in the left lower lobe. Bronchofiberscopy revealed an endobronchial polypoid mass obstructing the lower lobe bronchus at the orifice of left B10. Lt lower lobectomy was performed. Histopathological examination of the specimen showed the tumor (4.5 x 3.6 x 3.6 cm) developing not only within the tracheal lumen, but also in the lung tissue. Because immunohistochemical staining for desmin and alpha-smooth muscle actin was positive, we diagnosed leiomyoma. As MRI revealed multiple uterine masses after operation, we discussed the diagnostic problems in the relation to metastasizing leiomyoma of the uterus.

Acanthotic type of eccrine poroma on the arm: report of a case

A 72-year-old Japanese man with eccrine poroma on the arm is described. To the best of our knowledge, he is the fifth patient with this tumor on the arm reported from Japan. The histopathological type of the tumor of our patient was unique because it was acanthotic; those of the previous patients were all of the intradermal type.

Fan-shaped hepatic parenchymal damage after ethanol injection therapy for hepatocellular carcinoma: MRI appearances

BACKGROUND

T1- and T2-weighted magnetic resonance (MR) images frequently show fan-shaped areas of hypo- or hyperintensity in the hepatic parenchyma adjacent to a treated hepatocellular carcinoma after percutaneous ethanol injection (PEI) therapy. These areas correspond to abnormal contrast enhancement on serial dynamic MR images. The purpose of the present study was to describe the location, appearance, and frequency of these abnormalities because it is important to understand these entities for the correct assessment of therapeutic efficacy.

METHODS

MR imaging including a multisection dynamic study was performed in 20 consecutive patients with hepatocellular carcinoma treated with PEI therapy. We retrospectively evaluated the presence of fan-shaped hypointensities adjacent to treated tumors in the liver parenchyma on T1-weighted images and hyperintensities on T2-weighted images and corresponding fan-shaped contrast enhancement on both arterial-dominant and delayed-phase dynamic MR images. We review the location, appearance, and frequency of these findings, and we discuss the possible causes on the basis of pathologic examinations.

RESULTS

Seven (35%) of the 20 patients showed fan-shaped hyperintense areas adjacent to the treated tumors on T2-weighted images. These areas showed isointensity in five patients and hypointensity in two patients on T1-weighted images. Of these seven patients, one (14%) underwent the MR imaging within 1 month after the completion of PEI therapy, and six (86%) had it 2-9 months after the completion of PEI therapy (mean = 6 months). In all seven patients, fan-shaped hyperperfusion abnormalities corresponding to these areas of hyperintensity on T2-weighted images were seen on both arterial-dominant and delayed-phase dynamic MR images. Pathologically, the coagulative necrosis of the hepatocytes with sinusoidal dilatation and the restoration by the development of fibrous tissue were seen in these fan-shaped areas.

CONCLUSION

The fan-shaped areas of abnormal intensity on T1- and T2-weighted images and contrast enhancement on dynamic MR images seem to be attributable to pathologic changes in the normal liver parenchyma induced by the toxic reaction of ethanol. Awareness of the occurrence of such abnormalities in the peripheral liver parenchyma adjacent to the treated tumor is important for the correct assessment of therapeutic efficacy.

A case of Zollinger-Ellison syndrome produced by gastrinoma in the duodenum accompanied with multiple endocrine neoplasia type 1

A case of Zollinger-Ellison syndrome produced by gastrinoma in the duodenum accompanied by multiple endocrine neoplasia type-1 (MEN-1) is reported. A 46 year-old female underwent distal gastrectomy due to gastric ulcer 5 years ago. As ulceration of the residual stomach recurred, further examination was performed. Hyperprolactinemia, hypergastrinemia, primary hyperparathyroidism, pancreatic tumor, and duodenal carcinoid were evident, and the diagnoses of Zollinger-Ellison syndrome and MEN-1 were established. The origin of the gastrin secretion was suspected to be from the pancreatic tumor, so sampling of the portal blood was performed. As lesion on the gastrinoma in the pancreas could not be identified, total parathyroidectomy was performed for primary hyperparathyroidism. The level of the gastrin secretion, however, remained high. Partial resection of the duodenum for the duodenal carcinoid and a distal pancreatectomy were carried out concurrently. Immunohistochemical study of the anti-gastrin antibody revealed duodenal tumor cells. Initially, the gastrinoma was thought to be in the pancreas, however, the lesion accompanied with MEN-1 and the Zollinger-Ellison syndrome had occurred in the duodenum.

Basaloid squamous carcinoma of the esophagus with analysis by in situ nick end labeling and PCNA immunostaining

BACKGROUND/AIMS

Basaloid squamous carcinoma (BSC) of the esophagus has been associated with poor outcome after surgery. In this study, apoptosis and cell proliferation of BSC were studied to evaluate the malignant potential of this cancer.

METHODOLOGY

In tissue samples from 4 out of 5 BSC patients (1 patient with pre-operative radiotherapy was excluded) and from 30 patients with squamous cell carcinomas (SCCs) of the esophagus, apoptosis was studied by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL), and cell proliferation was evaluated by the immunostaining of proliferating cell nuclear antigen (PCNA). Two of the 5 patients with BSC died of recurrence and the remaining 2 patients are alive without recurrence.

RESULTS

TUNEL-positive cells and PCNA-positive cells were observed to exist randomly and independently in the BSC samples. In the well- and moderately differentiated SCCs, TUNEL-positive cells and PCNA-positive cells were locally observed. The apoptotic index was significantly lower in the BSC than in the SCC tissues, and the PCNA labeling index was significantly higher in BSC than in SCC.

CONCLUSIONS

These results suggest that BSC of the esophagus has great proliferative activity and weak apoptosis. These characteristics may reflect the aggressive behavior and poor prognosis of esophageal BSC. Early detection of this tumor, as in the present 2 cases, will contribute to a better prognosis.

Calcitonin gene-related peptide-like immunoreactive motoneurons innervating the canine intrinsic laryngeal muscles

The percentage of calcitonin gene-related peptide (CGRP)-immunoreactive motoneurons in the nucleus ambiguus innervating the intrinsic laryngeal muscles of colchicine-treated dogs was examined by using cholera toxin B subunit-gold (CTBG) as a retrograde tracer and by immunohistochemistry. Neurons that were labeled with CTBG from the cricothyroid muscle were located in the ventromedial division of the rostral part of the nucleus ambiguus, and the ratio of CGRP-positive neurons was 93.0%. Neurons labeled with CTBG from the thyroarytenoid muscle were located in the dorsal division of the medial part of the nucleus ambiguus, and the percentage of neurons with CGRP was 71.4%. Neurons labeled with CTBG from the posterior cricoarytenoid muscle were located in the ventral division of the medial part of the nucleus ambiguus, and the percentage of CGRP-positive neurons was 85.5%. These findings suggest that the innervation and/or the neurotrophic mechanism involving CGRP for each intrinsic laryngeal muscle is different.

[Comparative studies of breath-hold magnetic resonance cholangiopancreatography (MRCP) between different two sequences and between 1.0T and 1.5T units]

In this article, a comparative study in the diagnostic ability of a breath-hold MRCP between thin slice half-Fourier acquisition single-shot turbo spin-echo (HASTE) and thick slice rapid acquisition with relaxation enhancement (RARE), and between 1.5T and 1.0T units was made. Although thin slice HASTE sequence might be more excellent in the diagnostic ability than thick slice RARE, the ability of depiction of pancreaticobiliary system on MRCP was not statistically different between these two sequences and between 1.0T and 1.5T units. Thick slice RARE sequence was inferior to thin slice HASTE in the depiction of gallbladder stone. However, thick slice RARE sequence was useful for MRCP because a projection image of pancreaticobiliary system could be easily obtained without postprocessing and without misregistration. Thick slice RARE sequence should be used in combination with thin slice HASTE sequence for the diagnosis of pancreaticobiliary system.

[Efficacy of multidirection MRCP]

Pancreatobiliary system has complex and thin structure except for gallbladder, thereby MRCP having lower spatial resolution gives sufficient information compared with the direct cholangiopancreatography. Multidirection MRCP using HASTE sequence obtains the data in plane to compensate the lower spatial resolution, thus high detectability of all over pancreatobiliary system is performed in a few minutes. This technique overcomes the demerits pointed by former investigators and gives sufficient information to diagnose the pancreatobiliary diseases.

Evidence for mRNA expression of vascular endothelial growth factor by X-ray irradiation in a lung squamous carcinoma cell line

Vascular endothelial growth factor (VEGF) is a multipotent cytokine which plays an important role in various angiogenic conditions as well as in some tumor behaviors. Here we examined the induction of VEGF mRNA by X-ray irradiation in a lung squamous cell carcinoma cell line (RERF-LC-AI). Irradiating the cells with 15 Gy X-rays significantly increased the mRNA expression up to 2.5-fold of control at a post-irradiation time of 16-24 h. The induction of VEGF mRNA by X-ray irradiation was completely blocked by treating cells with either genistein (Src tyrosine kinase inhibitor) or H7 (protein kinase C inhibitor). This suggests that the mechanism of induction might be concerned with the pathway which triggers Src tyrosine kinase of the cell surface and the protein kinase C pathway.

Two cases of gastric involvement of esophageal cancer: intramural metastasis and intramural lymph node metastasis

Cases of esophageal cancer with intramural metastasis to the stomach and esophageal cancer with metastasis to an intramural lymph node of the stomach are herein reported. The former patient was a 52 year-old male. Squamous cell carcinoma (SCC) of the lower esophagus with an intramural metastasis located at the gastric cardia and a small leiomyoma at the fornix were resected. The latter patient was a 70 year-old female. SCC of the lower esophagus and an intramural lymph node metastasis located at the anterior wall of the gastric cardia were resected. The patient died nevertheless of multiple liver metastases. These gastric involvements were detectable by endoscopy before surgery. The clinicopathological features of these esophageal cancers were characterized; the sites were the lower part of the esophagus, and extreme lymphatic and vascular invasions were shown histologically. The gastric tumors were located in the upper third of the stomach, and the findings revealed submucosal tumors. It is therefore important to discriminate other gastric tumors, and to resect them simultaneously with esophageal cancer when a gastric tube has been used for reconstruction after esophagectomy.

Multiple carcinoids of the duodenum accompanied by type I familial multiple endocrine neoplasia

A case of multiple carcinoid tumors of the duodenum accompanied by familial multiple endocrine neoplasia is reported. A 46-year-old man with duodenal polyps discovered during a mass screening was followed up for 5 years. In August 1994, a histological examination revealed carcinoid tumors, and he was thus referred to our hospital for surgery. He underwent a parathyroidectomy and cholecystectomy for primary hyperparathyroidism and cholecystolithiasis, respectively. The patient's sister had also undergone a parathyroidectomy and distal pancreatectomy for primary hyperparathyroidism and insulinoma of the pancreas. In addition, his two children were also followed up for hypercalcemia. A serum examination of the patient revealed high levels of somatostatin and pancreatic polypeptide, but normal levels of gastrin and serotonin. In November 1994, a pancreaticoduodenectomy with a D2 lymph node dissection was performed. The macroscopic findings of the resected specimen showed multiple polypoid lesions with delles on the top, measuring 3 to 15 mm in size throughout the duodenum. A microscopic examination revealed the tumor to have infiltrated into the submucosa extensively, and an immunohistochemical analysis also demonstrated the tumor cells to be positive for somatostatin, but not for pancreatic polypeptide. After surgery, the serum level of somatostatin returned to normal but the pancreatic polypeptide remained high. The post-operative course was uneventful, and the patient remains in good health.

Mouse skin reactions following fractionated irradiation with carbon ions

PURPOSE

Skin reactions in the mouse leg following various daily doses given with 290 MeV/u carbon ions were investigated.

MATERIALS AND METHODS

Seven different LET (linear energy transfer) values ranging from 14 to 100keV/microm were selected. The fractionation schedules were 1-, 2-, 4- and 8-daily fractions. The isoeffect doses to produce moist desquamation on the dose-response curves were calculated with 95% confidence limits.

RESULTS

The isoeffect doses for carbon ions of 14 and 20 keV/microm increased with an increase in the number of fractions up to 4 fractions, but became constant when the number of fractions further increased to 8 fractions. This leveling off in isoeffect dose was more prominent for 40 keV/microm. Recovered dose per fraction was largest for 2 fractions of the 14keV/microm carbon beam. The isoeffect doses for 50, 60, 80 and 100keV/microm consistently increased with an increase in the number of fractions and did not show saturation up to 8 fractions. RBE (relative biological effectiveness) increased linearly with LET for all fractionation schedules.

CONCLUSIONS

These results suggest that daily fractionation with carbon ions could spare radiation damage in patients, and that changes the fractionation schedule affect clinical outcome.