Lymphoscintigraphy in tumors of the head and neck using double tracer technique

Knowledge of possible lymphatic drainage may facilitate planning of surgery for patients with head and neck tumors. Therefore, the aim of this study was to present a method of lymphoscintigraphy with special attention to an accurate correlation of lymphatic drainage to anatomic regions.

METHODS

Lymphoscintigraphy was performed using a double tracer technique before surgery in a total of 75 patients with squamous cell carcinoma of the head and neck. All patients received 100 MBq 99mTc-colloid at three to four peritumoral sites. A perchlorate solution (2 mL) was given orally to block salivary glands and the thyroid gland. Patients received 50 MBq 99mTc-pertechnetate intravenously for body contouring 20 min postinjection. Planar images were obtained over 5 min each, at 30 min and 4 h postinjection from anterior, right lateral and left lateral views with a large-field-of-view gamma camera. Lymphatic drainage was assessed by visual inspection and assigned to six cervical compartments.

RESULTS

Neither the salivary glands nor the thyroid gland were seen in any of the patients. In 22 of 75 patients (29.3%), the injection site was the only focal tracer uptake seen. In contrast, lymphatic drainage was identified in the remaining 53 patients (70.7%), and lymph nodes could be assigned easily to the six cervical compartments. Of 75 patients, 36 (48%) exhibited ipsilateral lymphatic drainage. In addition, 17 patients (22.7%) with unilateral tumor showed bilateral (n = 12), contralateral (n = 2) or retropharyngeal (n = 3) lymphatic drainage. In 3 of these 17 patients, bilateral lymph node metastases were proven. A subgroup of 12 patients (16%) exhibited N2c nodal status, despite a unilateral localized primary tumor. In 3 of these 12 patients, surgery was extended as a result of scintigraphic findings from unilateral toward bilateral neck dissection, and histology confirmed nodal involvement in these patients.

CONCLUSION

Lymphoscintigraphy using the double tracer technique allows an accurate correlation of lymphatic drainage to the six cervical compartments. This may provide the basis for a re-evaluation of its impact in treatment planning of patients with head and neck tumors.

Prognostic significance of serum S100B detection compared with routine blood parameters in advanced metastatic melanoma patients

Recent reports on the use of a quantitative measurement of S100B protein for the detection of metastatic melanoma have yielded promising results. In this study we evaluated 489 serum samples from 64 patients suffering from advanced melanoma (UICC/AJCC stage IV) to compare the sensitivity of a S100B immunoradiometric assay (IRMA) with that of conventional blood parameters as well as other known clinical prognostic factors. In a univariate statistical analysis, gender, bone metastasis, and lactate dehydrogenase and S100B levels in serum samples were found to be significant prognostic markers (P<0.05). The S100B level represented the only relevant independent prognostic marker that was sustained in a multivariate analysis (P = 0.016). Furthermore, we were able to demonstrate that S100B is of relevance irrespective of the specific sites of metastatic involvement. The other laboratory parameters could not match the sensitivity rate of S100B. Overall survival rate was strongly associated with serum S100B values. The results of our study suggest that S100B might be a useful tool as a melanoma marker and an independent prognostic factor in advanced metastatic melanoma. S100B serum detection is likely to be of great interest for the pretreatment stratification and/or monitoring of patients enrolled in clinical studies.

Angiotensin type 2 receptor is important in the normal development of the ureter

In humans, the actions of angiotensin II are transduced through the AT1 and AT2 receptors which have recently been implicated in renal organogenesis. Polymorphisms in the human angiotensin II receptor genes have been linked to cardiovascular and nephrological disorders. In this study we evaluated 35 patients with either primary obstructive megaureter or posterior urethral valves. Each was genotyped for the A1166 AT1 polymorphism and the recently described A-1332G AT2 transition. The incidence of these genetic variants was also evaluated in normal controls without any ultrasonographic urological abnormalities. Similar to our previous findings in congenital urological abnormalities, the AT1 receptor genotype distribution did not differ between patients with either primary obstructive megaureter or posterior urethral valves versus controls. In contrast, compared with normal controls, there was a dramatic increase in the occurrence of the AT2 A-1332G transition in patients with primary obstructive megaureter (75.0% vs. 41.9% in controls, P<0.025). In patients with posterior urethral valves, there was no difference in the occurrence of the transition versus controls (36.9%, P=NS). Thus, there is no correlation between the AT1 receptor gene polymorphism and urological abnormalities. However there is an increased incidence in the AT2 genetic variant in patients with primary obstructive megaureter.

Quantitative salivary gland scintigraphy

OBJECTIVE

Uptake of 99mTc-pertechnetate in salivary glands reflects intact salivary gland parenchyma. However, no standardized protocol for an accurate quantification of parenchymal function has been established so far.

METHODS

In this paper we report on a validated acquisition protocol supplying a normal database for standardized quantitative salivary gland scintigraphy.

RESULTS

The major advantage of salivary gland scintigraphy, as compared to other imaging modalities, is that both parenchymal function and excretion fraction of all four major salivary glands (i.e., parotid and submandibular glands) can be simultaneously quantified with a single intravenous injection.

CONCLUSION

Quantitative salivary gland scintigraphy is demonstrated to be a suitable imaging modality for research applications in evaluating the effects of radioprotective drugs on salivary glands. Salivary gland scintigraphy is easy to perform, reproducible and well-tolerated by the patient.

Beta 1 integrin expression in adenocarcinoma of Barrett's esophagus

BACKGROUND/AIMS

In vitro and in vivo studies did not show that beta 1 integrin expression is associated with malignant transformation or that it is of prognostic value in some malignant tumors. There are no data on the expression or prognostic value of beta 1 integrins in adenocarcinoma of Barrett's esophagus.

METHODOLOGY

We assessed the expression pattern and the prognostic impact of beta 1 integrins in paraffin-embedded specimens of 41 patients with adenocarcinoma of Barrett's esophagus by immunochemistry. At the time of investigation, neither histomorphological parameters nor the survival time were known.

RESULTS

There was no correlation between histomorphological parameters and the expression of beta 1 integrins. The expression of beta 1 integrins had no influence on long- term survival. There was a relationship between the prognosis and the following histopathological parameters: pT, pN and pM category, the UICC stage, the presence of lymphangiosis, and the DNA content of the tumor cells.

CONCLUSIONS

The preliminary results obtained in this study did not show that the expression of beta 1 integrins was of prognostic value in patients with adenocarcinoma of Barrett's esophagus. Further studies in a larger number of patients are required to confirm the results obtained in this investigation.

Salivary gland protection by amifostine in high-dose radioiodine therapy of differentiated thyroid cancer

BACKGROUND

Salivary gland impairment following high-dose radioiodine treatment is a well-recognized side effect, in general caused by free radicals. Therefore, it seemed promising to evaluate the radioprotective effect of the radical scavenger amifostine in patients receiving high-dose radioiodine therapy.

PATIENTS AND METHOD

Quantitative salivary gland scintigraphy using 100 to 120 MBq Tc-99m-pertechnetate was performed in 17 patients with differentiated thyroid cancer prior to and 3 months after radioiodine treatment with 6 GBq I-131. Eight patients were treated with 500 mg/m2 amifostine prior to high-dose radioiodine treatment and compared retrospectively with 9 control patients. Xerostomia was graded according to WHO criteria.

RESULTS

In 9 control patients high-dose radioiodine treatment significantly (p < 0.01) reduced Tc-99m-pertechnetate uptake by 35.4 +/- 22.0% and 31.7 +/- 21.1% in parotid and submandibular glands, respectively. Of these 9 patients, 3 exhibited xerostomia Grade I (WHO). In contrast, in 8 amifostine-treated patients, there was no significant (p = 0.878) decrease in parenchymal function following high-dose radioiodine treatment, and xerostomia did not occur in any of them.

CONCLUSION

Parenchymal damage in salivary glands induced by high-dose radioiodine treatment can be reduced significantly by amifostine. This may help to increase patients' quality of life in differentiated thyroid cancer.

Somatostatin receptor scintigraphy in postsurgical follow-up examinations of meningioma

Surgery is the treatment of choice in patients with meningioma. However, the risk of postoperative, local recurrence is well-known since total resection is not always feasible. Moreover, in these patients MRI may fail to differentiate between tumor remnants, recurrent meningioma or nonspecific hyperperfusion. In this study, the value of functional imaging using somatostatin receptor scintigraphy (SRS) was evaluated in postsurgical follow-up.

METHODS

Before and 2-3 mo after surgery, 27 patients with meningioma received MRI as well as SRS after intravenous injection of 200 MBq 111In-octreotide. Planar whole-body images were obtained at 10 min, 1, 4 and 24 hr postinjection, and SPECT was performed at 4 and 24 hr postinjection. The final diagnosis was proven histologically in all patients.

RESULTS

Before surgery, MRI showed focal contrast enhancement in all patients, and SRS revealed focal accumulation of 111In-octreotide. Thus, MRI and SRS yielded comparable results in all 27 patients. After surgery, MRI showed diffuse contrast enhancement in the area of the primary tumor site in all patients. Thus, MRI did not allow a differentiation between tumor and nonspecific hyperperfusion. In contrast, SRS revealed focal accumulation of 111In-octreotide in 16 of 27 patients indicating remaining tumor tissue or relapse of meningioma. This resulted either in an operative revision or in more frequent postsurgical follow-up examinations. In 11 of 27 patients, SRS was negative. Thus, total resection of meningioma was assumed, and no further interventions were performed.

CONCLUSION

Functional imaging using SRS is a highly specific imaging modality and has a significant impact in postsurgical follow-up in patients with meningioma.

Salivary gland protection by amifostine in high-dose radioiodine treatment: results of a double-blind placebo-controlled study

PURPOSE

Salivary gland impairment is a well-recognized side effect following high-dose radioiodine treatment (HD-RIT). Since differentiated thyroid cancer has a good prognosis, reduction of long-term side effects is important. Therefore, the effect of amifostine was studied in HD-RIT.

PATIENTS AND METHODS

Parenchymal function was assessed by quantitative salivary gland scintigraphy performed prospectively in 50 patients with differentiated thyroid cancer before and 3 months after HD-RIT with either 3 GBq iodine ((131)I) (n=21) or 6 GBq (131)I (n=29) in a double-blind, placebo-controlled study. Twenty-five patients were treated with 500 mg/m2 amifostine intravenously before HD-RIT and 25 patients served as controls, who received physiologic saline solution. Xerostomia was graded according to World Health Organization (WHO) criteria.

RESULTS

Before HD-RIT in 25 control patients, uptake of technetium-99m (99mTc)-pertechnetate was 0.45%+/-0.16% and 0.42%+/-0.16% in parotid and submandibular glands, respectively. Three months after HD-RIT, parenchymal function was significantly (P < .001) reduced by 40.2%+/-14.1% and 39.9%+/-15.3% in parotid and submandibular glands, respectively. Nine control patients developed grade I and two grade II xerostomia. In 25 amifostine-treated patients, uptake of 99mTc-pertechnetate was 0.46%+/-0.16% and 0.43%+/-0.17% in parotid and submandibular glands, respectively. Three months after HD-RIT, parenchymal function of salivary glands was not significantly altered (P=.691) and xerostomia did not occur in any of these patients.

CONCLUSION

Parenchymal damage in salivary glands caused by HD-RIT can significantly be reduced by amifostine, which may improve the quality of life of patients with differentiated thyroid cancer.

[Expression of CD44 and isoforms v4, v5, v6, v7, v10--new prognostic parameters in ductal pancreatic carcinoma?]

Prognostically relevant factors based on the histological assessment of the resected pancreas are known. However, additional parameters, such as biological staging of the intrinsic malignant potentiality of the tumor, would be useful. There has been no uniform finding of a relationship between CD44 variant expression and tumor progression.

METHOD

We assessed the expression pattern and prognostic impact of CD44 standard and CD44 isoforms v4, v5, v6, v7 and v10 in 40 ductal pancreatic carcinomas by immunochemistry on paraffin-embedded tumor material in patients after tumor resection. At the time of the investigation neither histomorphological parameters nor the survival time were known.

RESULTS

There was no correlation between the histomorphological parameter and the expression of CD44 splice variants. CD44 splice variants v4-v10 were almost only expressed in tumor tissue. In ductal pancreatic carcinoma, patients with an overexpression of CD44 splice variants had a worse prognosis. However, because of the small number of cases this was statistically not significant.

CONCLUSION

CD44 splice variants may have an influence on prognosis in ductal pancreatic carcinoma. However, further investigation on a larger number of patients is necessary to confirm these results.

Expression of CD44 variant proteins in adenocarcinoma of Barrett's esophagus and its relation to prognosis

BACKGROUND

None of the commonly used staging criteria accurately determine the prognosis of a patient with adenocarcinoma of Barrett's esophagus. The authors therefore assessed the expression pattern and prognostic impact of CD44 standard and CD44 isoforms CD44v4, v5,v6,v7, and v10 in adenocarcinoma of Barrett's esophagus.

METHODS

Specimens from 41 patients with adenocarcinoma of Barrett's esophagus who underwent esophageal resection were embedded in paraffin and studied immunohistochemically to determine the expression of CD44 splice variants. Histomorphologic parameters and survival time were not known at the time of the investigation.

RESULTS

Correlations between favorable clinical or histomorphologic parameters and CD44s or any of the split variants could not be established. Down-regulation of CD44s and the split variant v10 was significantly correlated with pT classification. Furthermore, down-regulation of CD44v10 and up-regulation of CD44v7 were significantly correlated with ploidy. There was a significant correlation between CD44s and split variants in tumorous and nontumorous tissue from the same patient. Down-regulation of CD44s and CD44v4 had a significant influence on prognosis in that it was associated with shortened life expectancy. Multivariate analysis revealed that the expression of CD44v4 was an independent factor in prognosis.

CONCLUSIONS

The results obtained for this small patient sample suggest that CD44v4 is a new independent prognostic parameter for adenocarcinoma of Barrett's esophagus that can be determined preoperatively by biopsy. It may therefore be helpful in planning therapy by allowing the identification of patients who may benefit from esophageal resection as well as those who are at high risk for morbidity and mortality even when the tumor is otherwise resectable. Further studies of larger patient samples are required to validate the results of the current study.

Radioprotection of salivary glands by amifostine in high-dose radioiodine therapy

Salivary gland impairment after high-dose radioiodine treatment is well recognized. Because differentiated thyroid cancer has a good prognosis, reduction of long-term side effects is important. This study investigated the radioprotective effects of amifostine in animals and humans receiving high-dose radioiodine therapy.

METHODS

Quantitative salivary gland scintigraphy was performed in five rabbits before and up to 3 mo after high-dose radioiodine therapy applying 1 GBq 131I. Three animals received 200 mg/kg amifostine before high-dose radioiodine therapy, and two served as controls. All animals were examined histopathologically. Quantitative salivary gland scintigraphy also was performed in 17 patients with differentiated thyroid cancer before and 3 mo after high-dose radioiodine therapy with 6 GBq 131I. Eight patients were treated with 500 mg/m2 amifostine before high-dose radioiodine therapy, and nine served as controls.

RESULTS

In two control rabbits, high-dose radioiodine therapy significantly reduced parenchymal function by 63% and 46% in parotid and submandibular glands, respectively. In contrast, there was no significant decrease in parenchymal function in amifostine-treated animals. Histopathologically, lipomatosis was observed in control animals but was negligible in amifostine-treated animals. Similar findings were observed in differentiated thyroid cancer patients. In nine control patients, high-dose radioiodine therapy significantly (p < 0.01) reduced parenchymal function by 37% and 31% in parotid and submandibular glands, respectively. Three patients exhibited Grade I (World Health Organization) xerostomia. In contrast, there was no significant decrease in parenchymal function in amifostine-treated patients and no incidence of xerostomia.

CONCLUSION

Parenchymal damage in salivary glands induced by high-dose radioiodine therapy can be reduced significantly by amifostine. This may increase the quality of life of patients with differentiated thyroid cancer.

Somatostatin receptor scintigraphy in small-cell lung cancer: results of a multicenter study

The aims of this study were to determine the accuracy of somatostatin receptor scintigraphy in the detection of the primary tumor and its metastases in small-cell lung cancer (SCLC) in a large patient population, and to investigate the course of somatostatin uptake in primary tumors during therapy.

METHODS

In a total of 100 patients, 134 examinations were performed. Twenty-seven of the patients were examined before and after chemotherapy. Planar whole-body images were acquired 4 hr and 24 hr after injection of approximately 200 MBq (111)In-pentetreotide. SPECT of the thorax was performed after 24 hr. Tumor-to-background (T/B) ratios for the primary tumor were averaged from anterior and posterior projections.

RESULTS

Compared to conventional investigations, somatostatin receptor scintigraphy (SRS) visualized the primary tumor with varying degrees of uptake in 96% of the examinations. Regional metastases and distant metastases were detected in 60% and 45% of the examinations, respectively. The uptake of the somatostatin analog by the primary tumor was significantly lower in the patients examined during chemotherapy as compared to those examined before treatment (T/B ratio = 1.94+/-0.79 versus 2.35+/-0.9, p < 0.005). A decrease in T/B ratio was noted in patients with remission at the time of SRS (from 2.40+/-1.56 to 1.63+/-0.72, p < 0.05). No difference in the pretreatment uptake of octreotide by the primary tumor was identified between patients with tumor progression and those with partial or complete remission.

CONCLUSION

Somatostatin receptor scintigraphy has a high sensitivity in the detection of the primary tumor in SCLC but fails in the detection of metastases. Thus, SRS does not provide useful information for staging of SCLC. Since somatostatin uptake by the primary tumor is affected by chemotherapy, it may be used to follow up on the course of SCLC.

[Lymphoscintigraphy with double tracer technique in carcinomas of the head-neck region]

BACKGROUND

Lymphoscintigraphy has been used since the early 1960s to demonstrate lymphatic drainage of head and neck tumors, but did not prove satisfactory. With the increasing importance of highly sophisticated neck dissection procedures, lymphoscintigraphy may have greater diagnostic impact. This assumes that lymphoscintigraphy will allow an accurate correlation of lymphatic drainage with anatomic structures. In this paper, we report on a method of lymphoscintigraphy with simultaneous body contouring.

METHODS

Double-tracer lymphoscintigraphy was performed in 78 patients with squamous cell carcinoma. Patients received 100 MBq 99mTc-colloid in 0.1-0.2 ml in 3-4 peritumoral localizations. Ten patients were injected during surgery. Two milliliters of perchlorate solution were given orally in order to block the thyroid. Twenty minutes later patients received 50 MBq 99mTc-pertechnetate i.v. for body contouring. Planar images were obtained over 5 min each at 30 min and 4-6 h after injection from anterior, right lateral and left lateral using a LFOV-gamma camera.

RESULTS

The thyroid was not visualized in any of the patients. In 28 of 78 patients (36%), the injection site was the only focal activity seen. In 50 of 78 patients (64%), lymph drainage was observed. Thirty-six of 78 patients (46%) showed unilateral lymphatic drainage, and 14 of 78 (18%) showed bilateral drainage. In all 50 patients showing lymphatic drainage, lymph nodes could be easily assigned to the six cervical lymph node compartments described.

CONCLUSIONS

Double-tracer lymphoscintigraphy enables an accurate correlation of cervical lymph nodes and anatomic structures of the head and neck region. These findings suggest that the impact of these studies on the preoperative planning for neck dissection should be reevaluated.

Loss of heterozygosity studies and deletion mapping identify two putative chromosome 14q tumor suppressor loci in renal oncocytomas

Renal oncocytoma is considered to be a benign tumor that shares some phenotypic features with chromophobe renal cell carcinoma (RCC). Recently, we described high frequencies of allelic loss at 1p, 2p, 6p, 10p, 13q, 14q, 17p, and 21q, which correlate significantly with the chromophobe subtype of RCC. To investigate the genetic relationship between these two entities, we examined 12 oncocytomas for loss of heterozygosity (LOH) at these regions. In addition, we included markers for 3p, 5q, 7q, 11p, and 22q. The only chromosomal region showing similarly high frequencies of allelic loss for both subtypes was 14q. Therefore, a genetic relationship between renal oncocytoma and chromophobe RCC seems questionable. Eight of 12 oncocytomas (67%) showed LOH at 14q, a frequency that was significantly higher (P < 0.001, chi(2) test) than the frequencies of LOH in all other regions. To define regions potentially harboring novel tumor suppressor genes, we performed multifluorescence microsatellite analysis with 13 markers spanning 14q. Interstitial deletions at different regions of 14q were detected, with the highest frequencies at D14S258 (14q23-24.3) and D14S292 (14q32.1-32.2). 14q LOH might be associated with advanced-stage RCCs or other tumors, but it does not seem to indicate progression in oncocytomas. Its role in pathogenesis of renal oncocytomas remains to be clarified. Here, we provide evidence for two distinct tumor suppressor gene loci at 14q in renal oncocytoma, which will be useful for further fine-mapping studies of these critical regions.

[Implementation and indications for quantitative sialoscintigraphy]

BACKGROUND

Since its introduction in 1965 salivary gland scintigraphy has been an established method to simultaneously investigate excretion function in major salivary glands. In order to elucidate parenchymal function of salivary glands, several authors described various quantitative and semiquantitative methods. However, no standardized protocol for quantitative salivary gland scintigraphy has been established so far.

METHODS

Therefore, in this paper we report on a standardized and validated acquisition protocol for salivary gland scintigraphy using 99mTc-pertechnetate.

RESULTS

A normal data base for both parenchymal and excretion function is given in detail. In addition, the diagnostic value of salivary gland scintigraphy is reviewed in various clinical settings, such as mild parenchymal damage in beginning Sjögren's syndrome, proof of functional obstruction in sialolithiasis with and without parenchymal damage, and parenchymal damage following radioiodine treatment. In a second part, applications of salivary gland scintigraphy in current clinical research are described, and radiation protection of salivary glands in rabbits and patients treated with high doses of I-131 are discussed.

CONCLUSIONS

Salivary gland scintigraphy is a study that is easily performed and well tolerated by the patient. It yields quantitative parameters for parenchymal function and excretion fraction.

Quantification of diphosphonate uptake based on conventional bone scanning

Up to now there has been no routinely used and easy-to-perform method for the quantification of bone uptake. Therefore, we have evaluated the clinical practicability of a new and simple method for the measurement of bone uptake based upon conventional three-phase bone scanning. In 13 patients with normal bone scans, whole-body scintigrams were obtained at 3 min and 1, 2, 3, 4, 5, 6 and 24 h after injection of 600 MBq technetium-99m hydroxymethylene diphosphonate (HMDP). Using a conventional region of interest technique, fitted time-activity curves of soft tissue and urinary excretion were established, and bone uptake was calculated from these data as the total whole-body activity minus both soft tissue activity and urinary excretion. Subsequently, the new method was tested in routine patient management: 32 healthy patients and five patients with different types of metabolic bone disease were investigated, measurements being performed only at 3 min and 3-4 h p. i. during conventional three-phase bone scanning. In the multi-imaged patient subset, soft tissue activity decreased exponentially, reaching a plateau after 6 h with a residual activity of about 14% of initial total whole-body activity. Bone uptake reached quite a stable plateau of about 27% as early as 3 h p.i., with no significant changes up to 24 h. Healthy patients of the two-scan group showed no differences in bone uptake (mean uptake values were 24.1% in women and 26.9% in men), whereas in patients with metabolic bone disease bone uptake was significantly higher, with a mean of 48% (P <0.05). Thus, the results of this method are in good agreement with the findings of standard 24-h whole-body retention measurements. The new method, however, is easy to perform, allows assessment of pure bone uptake instead of whole-body retention, and permits calculation of bone uptake by only two measurements during routine three-phase bone scanning.

[Quantitative salivary gland scintigraphy--a recommended examination prior to and after radioiodine therapy]

AIM

The aim of this study was to evaluate possible deterioration of salivary gland function due to radioiodine therapy with low activities using standardized quantitative salivary gland scintigraphy (qSZ). In addition, the prevalence of sialopathies was estimated in patients with thyroid dysfunction.

METHODS

Prior to routine thyroid scintigraphy qSZ was performed after i.v. injection of 36-126 MBq 99mTc-pertechnetate, and both uptake and excretion fraction were calculated as a measure of parenchymal function and saliva excretion, respectively 312 healthy patients served as reference for a normal data base. 144 patients underwent qSZ prior to and 3 months after radioiodine therapy. Results of qSZ in another 674 thyroid patients were evaluated for determining the prevalence of salivary gland dysfunction.

RESULTS

Normal uptake was 0.45 +/- 0.14% and 0.39 +/- 0.12%, and normal excretion fraction amounted to 49.5 +/- 10.6% and 39.1 +/- 9.2% in parotid and submandibular glands, respectively. Despite salivary gland stimulation with ascorbic acid during radioiodine therapy a significant activity-related functional impairment of 14-90% could be measured after application of 0.4-24 GBq of 131I. Prevalence of pretreatment sialopathies was 77/674 = 11.4% in single glands, and there was a global salivary gland functional impairment in 52/674 = 7.7%.

CONCLUSION

Together with thyroid scintigraphy qSZ is an easy to perform examination without additional radiation burden. It can be recommended in all patients prior to and after radioiodine therapy both in order to quantify and to document possible parenchymal impairment induced even by low activities of 131I.

201Tl whole-body scintigraphy in patients with malignant melanoma

The aim of this study was to evaluate 201Tl whole-body imaging in the detection of metastases prior to surgery in patients with malignant melanoma. Whole-body imaging was performed in 30 patients with known or suspected metastases 5 and 30 min after administration of 150 MBq 201Tl. The imaging results were compared with the histopathological findings in each patient on a lesion-by-lesion basis. Of the 39 metastases proven histopathologically, 34 were detected by 201Tl imaging (sensitivity = 87%), including 4 in-transit metastases and one inguinal lymph node metastasis which were unknown prior to investigation. Due to these additional findings on 201Tl imaging, scheduled surgical therapy was changed in three patients. 201Tl imaging was false-negative in four lymph node metastases and one skin lesion, and there were two false-positive 201Tl scans with tracer accumulation in inflammatory sites. The mean target-to-background ratio on the true-positive scans was 1.72 +/- 0.37 and 1.67 +/- 0.41 (P > 0.05) at 5 and 30 min post-injection respectively. In conclusion, 201Tl whole-body imaging appears sensitive and simple to perform in the detection of metastases prior to surgery in melanoma patients.

Ventilation scintigraphy of the middle ear

In this study, an attempt was made to administer radioactive gas into the tympanic cavity to measure initial gas trappings as well as clearance from the middle ear to evaluate eustachian tube function.

METHODS

Twenty-eight patients were administered 50 MBq 133Xe gas. Three different methods for gas application were tested: (a) direct injection through a tympanostomy tube in two patients, (b) administration through a nasopharyngeal catheter combined with Valsalva maneuvers in six subjects without middle ear dysfunction and (c) insufflation into the pharyngeal space through a nose olive performed in 12 patients with normal eustachian tube function and in eight patients with one-sided tube dysfunction.

RESULTS

All three approaches were successful in visualizing middle ear ventilation, demonstrating tracer trapping within the tympanic cavities in 20 of 28 patients. Semiquantitative evaluation by region of interest techniques revealed a left-to-right uptake ratio of 48.4%-51.6% in 13 patients without tube dysfunction. Five patients with one-sided tube dysfunction showed a significantly lower median uptake of 31.6% (p = 0.01). The clearance half-lives ranged from 9 to 283 min in normal subjects and 37-64 min in patients with one-sided tube malfunction, demonstrating no statistically significant difference between the two groups and a trend towards increased washout in patients with tympanic dysfunction.

CONCLUSION

Middle ear ventilation scintigraphy with 133Xe through a nose olive is an easy-to-perform test to evaluate eustachian tube function and has a success rate of about 70%, thus, reflecting the complex physiological mechanisms involved.

[Scintigraphic evidence of silent aspiration after bilateral lung transplantation]

We present a case of a 25 year old patient who underwent double-sided lung transplantation and suffered from recurrent pneumonia. Silent aspiration was suspected clinically. Aspiration was proved by scintigraphy enabling to discriminate between direct oro-pulmonal aspiration and aspiration after gastro-esophageal reflux.

Quantitative salivary gland scintigraphy in the diagnosis of parenchymal damage after treatment with radioiodine

This study was undertaken to quantify salivary gland parenchymal damage after radioiodine treatment with a standard protective regimen of ascorbic acid. Altogether, 106 patients underwent quantitative salivary gland scintigraphy with 99Tcm-pertechnetate prior to and 3 months after radioiodine therapy. Parenchymal function was quantified by calculating 99Tcm-pertechnetate uptake 13 min post-injection. Patients received 131I doses ranging from 400 MBq to 24 GBq (cumulative). Among the patients who received large doses of 131I, severe parenchymal destruction could be visually analysed as well as quantitatively evaluated. In contrast, after low-dose radioiodine treatment, mild parenchymal impairment was demonstrated by quantitative evaluation only. In conclusion, standardized quantitative salivary gland scintigraphy is essential for the reliable detection of mild parenchymal malfunction. Despite the standard protection regimen using ascorbic acid as a sialogogue, radioiodine therapy induces loss of salivary gland parenchymal function even with low doses of 131I.

Allelic losses at chromosomes 1p, 2p, 6p, 10p, 13q, 17p, and 21q significantly correlate with the chromophobe subtype of renal cell carcinoma

We analyzed 50 sporadic renal cell carcinomas (RCCs) for loss of heterozygosity (LOH) at the chromosomal regions 1p, 2p, 6p, 7q, 10p, 11p, 13q, 14q, 17p, 21q, and 22q. Histologically, the tumors were distinguished into clear cell, chromophilic, and chromophobe carcinomas. Whereas LOH at 14q was identified in 42-64% of all three tumor types, only the chromophobe tumors showed high frequencies of LOH (73-91%) at 1p, 2p, 6p, 10p, 13q, 17p, and 21q. These findings provide substantial evidence that the chromophobe subtype of RCC represents a distinct genetic entity. Thus, specific LOH patterns may define the histogenesis and oncogenesis of chromophobe RCC and may be useful in tumor diagnosis and clinical prognosis.

The value of bone scanning in pre-operative decision-making in patients with progressive facial asymmetry

Hemimandibular elongation is characterized by persistent unilateral growth, resulting in unilateral overgrowth of the mandible. The surgical treatment strategy depends on condylar growth activity, which cannot be assessed by conventional radiological procedures. Therefore, this study was undertaken to evaluate the usefulness of bone scanning in hemimandibular elongation. Twenty-seven patients underwent bone scanning prior to surgery. Growth activity was quantified by calculating the L/R ratio. In the case of more pronounced right-sided growth producing a L/R ratio of less than 1, inverse values were used. Corrective osteotomy was performed in the patients with a L/R < 1.10, whereas patients with a L/R > 1.10 underwent condylectomy. Twenty-three patients had a L/R ratio < 1.10 and were followed up for 3 years. In 16 patients, a corrective osteotomy was performed without any relapse post-operatively. Four patients showed marked unilateral increased uptake. In one patient, a pre-operative bone scan was not considered, and corrective osteotomy was performed with subsequent recurrence of unilateral overgrowth of the mandible. The final patient underwent condylectomy without relapse. In two patients, it was decided to repeat the bone scan after a follow-up period of 12 months. In conclusion, bone scanning has significant clinical value in pre-operative decision-making in hemimandibular elongation by guiding surgical strategy with respect to condylar growth activity.

Somatostatin receptor scintigraphy in the differential diagnosis of meningioma

The aim of this study was to evaluate somatostatin receptor scintigraphy (SRS) in patients with meningioma proven or suspected on magnetic resonance imaging (MRI). Prior to surgery, 47 patients were investigated up to 24 h following the injection of 200 MBq 111In-octreotide. Tracer uptake was compared with the histological presence of meningioma. Histology revealed 43 meningiomas, 3 neurinomas and 1 ependymoma. A true-positive SRS result was obtained in 36 patients, in 13 of whom a tumour volume of < 10 ml was noted. A false-negative SRS result was obtained in seven patients, all of whom had a tumour volume of < 10 ml. Whereas MRI alone was decisive in 38 of 47 patients, it could only provide a differential diagnosis in the remaining 9 patients. A positive SRS result confirmed meningioma in five of these patients, and a negative SRS result excluded meningioma in the other four. Therefore, cases of SRS-negative meningioma do exist. Nevertheless, significant clinical benefit can be obtained from functional imaging with 111In-octreotide in patients with an inconclusive MRI result, as large meningiomas can be excluded by scintigraphy alone, whereas meningiomas of any size may be confirmed in combination with specific MRI results.

Somatostatin receptor scintigraphy in the staging of small cell lung cancer

The aim of this study was to evaluate somatostatin receptor scintigraphy (SRS) in the staging of patients with small cell lung cancer. Prior to chemotherapy, 20 patients were investigated up to 24 h following an injection of 200 MBq 111In-octreotide. Following chemotherapy and restaging, four patients were re-evaluated. Primary tumour was detected in 18 of 23 studies, which exhibited increasing target-to-back-ground ratios over time. Lymph node metastases and distant metastases were detected in 7 of 27 and 8 of 31 sites, respectively. Thus, the overall sensitivity for detecting metastases was less than 26%. SRS did not result in any upstaging of patients. We conclude that in patients with small cell lung cancer, functional imaging by SRS has no impact on clinical decision making.

The influence of cytokines on the adhesion of renal cancer cells to endothelium

PURPOSE

The development of tumor metastasis requires direct adhesive interactions between tumor cells and vascular endothelium. We examined the adherence of renal cell carcinoma (RCC) lines to endothelium after stimulation with different cytokines that induce expression of the vascular adhesion molecules endothelial leukocyte adhesion molecule (ELAM)-1, vascular cell adhesion molecule (VCAM)-1 and intercellular adhesion molecule (ICAM)-1,

MATERIALS AND METHODS

Human umbilical vein endothelial cells (HUVEC) were used to determine the adhesion of the RCC lines CCF-RC1, 2 and 7 to endothelium. Expression of cell adhesion molecules (CAM) on HUVEC and RCC lines was measured with immunoflowcytometry.

RESULTS

Stimulation of HUVEC with rIl-1 beta, rTNF-alpha, or PMA resulted in a time-dependent 1.4- to 2.9-fold increase of RCC adhesion to HUVEC. Significant increased tumor cell binding was observed after 4 hours and paralleled the time-dependent induction of ELAM-1 and VCAM-1. Immunocytometry demonstrated the presence of the ligands sialyl Lewis X and VLA-4 on RCC, and blocking studies with monoclonal antibodies directed against tumor cell-endothelial interactions mediated by VCAM-1/VLA-4 and ELAM-1/sialyl Lewis X demonstrated marked inhibition of tumor cell adherence to cytokine-stimulated HUVEC.

CONCLUSIONS

This study demonstrates that cytokine-induced increases in RCC adherence to HUVEC are mediated in part by VCAM-1/VLA-4 and ELAM-1/sialyl Lewis X interactions and suggest that these molecules may play an important role in the ability of RCC to metastasize.

Radiotherapy with iodine-131 in recurrent malignant struma ovarii

Malignant struma ovarii is a very rare disease and, therefore, there is neither common agreement on treatment regimens nor sufficient follow-up experience. We present a case of a 49-year-old woman with malignant struma ovarii of the follicular type, who received ablative radioiodine treatment after thyroidectomy and surgical removal of the primary tumour. During follow-up examinations an increasing thyroglobulin level was found, caused by a tumour relapse with suspected urinary bladder infiltration on CT and proven uptake of radioiodine on whole-body scanning with iodine-131. After administration of 6GBq 131I, complete tumour regression was achieved with no evidence of a new relapse during a 30-month follow-up period. Correspondingly, repeated thyroglobulin measurements were all negative. This case demonstrates the benefit of combined surgical and radioiodine treatment of malignant struma ovarii for both monitoring and therapy of relapse or metastases; thus, the same therapeutic regimen as is employed in primary differentiated thyroid carcinoma may be recommended.

A monoclonal antibody-cobra venom factor conjugate increases the tumor-specific uptake of a 99mTc-labeled anti-carcinoembryonic antigen antibody by a two-step approach

Monoclonal antibodies (mabs) have considerable potential for specific cancer treatment. However, due to the antigen heterogeneity and especially the low uptake in solid tumors, mabs have not been used successfully in most clinical trials to date. This study investigates the effects of a mab-cobra venom factor (CVF) conjugate in vitro and in vivo in an orthotopic pancreatic cancer model using nude rats. CVF, a nontoxic glycoprotein from cobra venom, permanently activates the alternative pathway of complement. Coupled to a mab with tumor-binding properties, the complement activation can be targeted to the tumor tissue. We studied the activity of a mab CA19-9-CVF conjugate with the human pancreatic cancer cells PancTu I. PancTu I cells express the complement resistance factors CD46, CD55, and CD59, as we demonstrated by immunostaining, an observation that may explain the lack of cytotoxicity of the CA19-9-CVF conjugate. However, using ELISA, Western blot, and immunostaining, we showed that CA19-9-CVF activates the complement cascade, including the release of the anaphylatoxin C3a, a mediator of an inflammatory reaction. The in vivo studies of CA19-9-CVF-treated nude rats showed an increased tumor infiltration by natural killer cells and macrophages. The tumor uptake of 99Tc-labeled anti-carcinoembryonic antigen antibody was increased approximately 2-fold in rats pretreated with 70 micrograms of CA19-9-CVF, compared to animals that received an equimolar mixture of noncoupled mab and CVF. This study indicates the value of mab-CVF conjugates in adjuvant immunotherapy. mab-CVF conjugates might be useful in pretargeting approaches by increasing the uptake of a therapeutic mab.

111In-octreotide imaging in patients with long-standing Graves' ophthalmopathy

The aim of this study was to examine patients with long-standing Graves' ophthalmopathy using 111In-octreotide scintigraphy. Sixteen patients with inactive ophthalmopathy of up to 114 months duration and 14 normals were investigated for 48 h following an injection of 200 MBq 111In-octreotide. No significant tracer accumulation in the orbital region could be identified in any of the patients with long-standing Graves' ophthalmopathy. The orbit to brain (O/B) ratios after 24 and 48 h were 2.39 +/- 0.36 and 2.15 +/- 0.44 versus 2.17 +/- 0.33 and 2.20 +/- 0.37 for the patients and normals, respectively (N.S.). 111In-octreotide accumulation in ophthalmopathy described in the literature may thus be a passing event limited to its active stage, which is consistent with the concept of imaging a lymphocytic infiltration. In this study, the lack of accumulation of 111In-octreotide in the orbital region during the inactive stage demonstrates an absence of somatostatin receptors in orbital tissue itself. Thus, in patients with inactive Graves' ophthalmopathy, there is no basis for a diagnostic approach with somatostatin.

Value of quantitative salivary gland scintigraphy in the early stage of Sjögren's syndrome

The aim of this study was to test the impact of quantitative salivary gland scintigraphy in patients with suspected Sjögren's syndrome. Thirteen patients with suspected Sjögren's syndrome were investigated. During clinical work-up, three had severe and four had mild Sjögren's syndrome, while six were normal. Quantitative salivary gland scintigraphy was performed using a standardized method. The normal data-base consisted of 172 patients without any evidence of salivary gland malfunction. Visual and quantitative comparisons of the patients' scintigrams were made. In the patients with severe Sjögren's syndrome, uptake was 0.10 +/- 0.04% and 0.09 +/- 0.03% in the parotid and submandibular glands respectively, confirming the visual diagnosis. In the patients without Sjögren's syndrome, concordance between the visual and quantitative evaluations could also be shown. In contrast, among the patients with mild Sjögren's syndrome, uptake was diminished (P < 0.05), amounting to 0.21 +/- 0.05% and 0.16 +/- 0.02% in the parotid and submandibular glands respectively, while visual analysis indicated normal parenchymatous function. In conclusion, quantitative salivary gland scintigraphy is essential for the reliable detection of parenchymatous malfunction at an early stage of Sjögren's syndrome, which may be missed by visual analysis alone.

[DACS--a cost-advantageous nuclear medical document archiving and communication system]

A simple and inexpensive solution for the complete digital management of a nuclear medical institution is presented. The starting point was provided by five different gamma cameras, one of which was equipped with a PC-based ICON computer. The remaining cameras were first adapted to ICONs and subsequently integrated into a Macintosh LAN, of 15 computers, allowing the entire image acquisition, processing, interpretation, documentation and archiving to be performed on the same comfortable menu-guided surface. Complete patient management is accomplished by a specific commercially available data base to which a specially developed image and document archive was connected. The system described provides complete digital management without the conventional filing systems at the moderate price of approximately DM 11 x 10(4) plus the cost of the new camera computers.

Tumor cell--endothelium adhesion in an artificial venule

Adhesion of tumor cells to endothelial cells is a crucial step in the complex sequence of metastasis. In addition to type and local density of adhesion molecules on both cell types, shear forces exerted by the blood flow have been described to be of major importance in governing cell adhesion. Most of the experiments on the molecular basis of tumor-endothelial cell adhesion have been performed as static assays which lack shear forces. We have developed an artificial venule which shares the following in vivo characteristics. A confluent layer of endothelial cells lines the luminal surface of a glass capillary of 1 mm i.d. with pores of 30 nm diameter to allow diffusion of molecules from outside the capillary. Physiological pressure of 16 mbar, flow rate of 2 cm/s, and shear forces of 2 dynes/cm2 are maintained. This device allowed us to show that under dynamic conditions adhesion of B16 mouse melanoma cells to EA.hy926 endothelial cells is mediated most likely by a lectin-like structure on B16 cells and oligosaccharide(s) on endothelial cells. In addition, endothelial activation-independent adhesion was found to be restricted to only a fraction of endothelial cells, as the number of B16 cells that adhered was independent of the number of B16 cells applied.

DACS – Ein kostengünstiges nuklearmedizinisches Dokumentenarchiv- und Kommunikationssystem

Es wird ein einfaches und kostengünstiges Lösungskonzept zur kompletten digitalen Verwaltung einer nuklearmedizinischen Klinik vorgestellt. Die Ausgangssituation war durch fünf unterschiedliche Gammakamerafabrikate vorgegeben, wovon eines bereits mit einem auf Macintosh-PC-Basis arbeitenden Rechner, ICON, ausgestattet war. Die verbleibenden vier Geräte wurden ebenfalls an ICON-PCs adaptiert und in ein Macintosh-LAN, bestehend aus weiteren 15 PCs, integriert, so daß die gesamte Bildakquisition, -Verarbeitung, Befundung, Dokumentation und Archivierung über eine einheitliche, benutzerfreundliche Oberfläche komplikationslos möglich ist. Die Patientendatenverwaltung erfolgt auf demselben LAN über ein kommerziell erhältliches Datenbanksystem, an das ein selbstentwickeltes Bild- und Dokumenten-Archiv angebunden worden ist. Das System erlaubt ein völlig aktenfreies Patienten-, Daten- und Bildmanagement zu vergleichsweise moderaten Kosten von etwa 11 × 104 DM neben den Aufwendungen für die neuen Kamerarechner.

[Dowling-Degos disease: unsuccessful therapeutic trial with retinoids]

A patient with the typical features of Dowling-Degos disease (reticulate pigmented anomaly of the flexures) is described; the clinical picture and differential diagnosis are discussed. Systemic retinoids were used for treatment, but no essential improvement could be observed.

UV-induced unscheduled DNA synthesis in human skin: dose response, correlation with erythema, time course and split dose exposure in vivo

Unscheduled DNA synthesis (UDS) has been shown to be saturated above a threshold dose of UV-C in human fibroblasts in vitro. We have investigated by autoradiography whether a similar saturation occurs in human skin in vivo with UV-B and whether this phenomenon correlates with the erythemal response. In addition, we determined the time course of UDS at 24 h after exposure and the effect of dual exposures separated by 24 h. The dose-response curve was established by exposure to 1/16, 1/8, 1/4, 1/2, 1, 2, 3, 4 and 6 MEDs UV-B. For the time-course study, areas exposed to 1/2 and 2 MEDs were biopsied after 1, 3, 6, 12 and 24 h. Autoradiography was performed in vitro. The dose-response curve showed a significant increase in UDS from 1/16 to 1 minimal erythema dose (MED), whereas no significant difference was observed between 1 MED and the higher UV-B doses tested. The 24 h time sequence revealed a gradual decrease in UDS activity. The 1/2 MED curve declined more rapidly and reached the zero-level between 12 h and 24 h, whereas about 50% of the initial UDS value was still retained 24 h after 2 MEDs. The dual-dose study revealed that a second hit of fractions of the MED resulted in lower levels of UDS than induced by these fractions alone in previously untreated areas. UDS increases with the erythemal dose between 1/16 and 1 MED. It reaches a plateau after 1 MED and cannot be increased by doses up to 6 MEDs, suggesting a saturation of excision repair in vivo. Time course studies support such a saturation phenomenon. The failure to increase significantly UDS by a second irradiation 24 h after the first exposure needs further clarification. Since persistence of DNA lesions may lead to an accumulation after repeated exposures, additional mechanisms other than excision repair may protect human skin by error-free removal of possibly mutagenic sites. Photoreactivation may be important in this respect.

Toxemia in a patient with none of the standard signs and symptoms of preeclampsia

A case of gravida presenting with upper abdominal pain, an elevated serum glutamic oxaloacetic transaminase level, and thrombocytopenia, all of which resolved promptly after delivery, and with none of the standard signs and symptoms needed for the diagnosis of preeclampsia is presented. The issues of how this case relates to preeclampsia, nomenclature, differential diagnosis, and management are discussed.

Severe preeclampsia with persistent postpartum hemolysis and thrombocytopenia treated by plasmapheresis

A case of severe preeclampsia in which hemolysis and rapid platelet consumption persisted after delivery, but in which the blood urea nitrogen and serum glutamic oxaloacetic acid transaminase levels returned to normal is presented. Antiplatelet aggregating medications and exchange plasmapheresis with fresh frozen plasma were begun on the eighth postpartum day, but the hemolysis and rapid platelet consumption did not begin to improve until the 12th postpartum day. The use of plasmapheresis in highly selected cases of severe preeclampsia with hemolysis and thrombocytopenia that do not resolve after delivery is discussed.

Photochemotherapy for cutaneous T cell lymphoma. A follow-up study

In 1975 we started a prospective study on oral methoxsalen photochemotherapy (PUVA) in cutaneous T cell lymphoma (CTCL). The first short-term follow-up of nineteen patients (1978) showed that PUVA may induce long-lasting remission in early stages, and that eventual relapses respond comparably well when PUVA is resumed. We now present the follow-up data of the original nineteen patients, covering a period of up to 7 years, and of an additional twenty-five patients who have entered the trial since April, 1977. Similar to earlier reports, all patients with eczematoid and plaque lesions (stages IA and IB) cleared. Likewise, eczematoid and plaque lesions in patients with early tumors (stage IIB) were cleared. During a mean follow-up of 44 months, 55% of stage IA patients and 39% of stage IB patients remained free of disease. In patients who experienced relapses, the mean disease-free interval was 20 months for stage IA and 17 months for stage IB. All patients with stage IIB experienced multiple relapses and only three of seven were alive after 6 years, despite additional x-ray or cytotoxic therapy. The observation in this study that five of nine stage IA patients and ten of twenty-six stage IB patients have remained in continuous remission after a single PUVA course for up to 79 months indicates that PUVA may induce long-lasting disease-free intervals if used in the early stage of disease. However, the observation period still does not prove whether permanent cure can be achieved in some cases or not.

[UV-B phototherapy in psoriasis]

67 patients, 41 with chronic plaque-psoriasis and 26 with acute eruptive or seborrhoic psoriasis, were treated in a stand-up unit equipped with UV-B fluorescent bulbs. 92 per cent of the latter group of patients showed satisfactory results (13 exposures, total UV-B dose: 464 mJ/cm2), whereas only 46 per cent of the patients with plaque psoriasis responded comparably (19 exposures, total UV-B dose: 994 mJ/cm2). A split comparison study of PUVA and UV-B on plaque-psoriasis revealed the superiority of PUVA in both initial treatment phase and duration of the remission. For certain types of psoriasis, UV-B phototherapy represents an alternative option. With regard to long-term hazards, however, as carcinogenicity in particular, UV-B has to be judged with the same scrutiny as PUVA.

[Cowden's disease--"multiple hamartoma syndrome"--with gastrointestinal manifestations]

A case report is given demonstrating changes of the intestinal tract in a patient with Morbus Cowden. The clinical picture of the disease is described including differential diagnosis. The high risk of accompanying malignant lesions and the need of early detection of the disease are pointed out.

Increased blood-brain transport of tryptophan after portacaval anastomoses in germ-free rats

Portal-systemic shunting in rats results in altered plasma concentrations of the large neutral amino acids (NAA), and increased blood-brain barrier NAA transport. Bacterial ammonia production in the bowel, especially the colon, is thought to play a major role in the etiology of portal-systemic encephalopathy (PSE). In order to isolate the role of bacteria in PSE, plasma and brain amino acids and ammonia (NH3) were studied in germ-free (GF) rats with portacaval shunts (PCS). Germ-free rats underwent end-to-side portacaval shunt or sham operation under germ-free conditions and were kept in a germ-free isolator under careful bacteriologic control. Similar operations were carried out on conventional animals. Two weeks post-operatively blood-brain transport of the neutral amino acid tryptophan was studied and the animals sacrificed. Plasma NH3 rose after PCS both in GF and in conventional rats. In germ-free and conventional rats with PCS, there was a significant elevation in plasma of the aromatic amino acids and decreased concentrations of the branched-chain amino acids. In the brain, both groups had elevated aromatic amino acids, while the branched-chain amino acids remained normal. The blood-brain transport of tryptophan was elevated in portacaval shunted rats, whether germ-free or conventional. These studies suggest the elevated plasma levels of ammonia and disturbances in plasma and brain amino acids seen after portacaval shunt are not dependent on the presence of gut bacteria.

Serum levels of 8-methoxypsoralen in two different drug preparations: correlation with photosensitivity and UV-A dose requirements for photochemotherapy

In a quantitative study we have compared the serum levels, the time course and the photosensitizing capacity of a conventional crystalline 8-methoxypsoralen brand and an investigational liquid formula. Evidence is presented showing that the liquid preparation is superior to the crystalline form: it peaks earlier after ingestion, it produces higher and more constant degree of photosensitization, it is eliminated more rapidly from the blood, and it requires a lower UV-A dose for eliciting photosensitivity reactions aiming at a reduction of the total cumulative UV-A dose required for clearing psoriasis.

[Cowden syndrome (multiple hamartoma syndrome)]

This report deals with a female patient with multiple hamartoma syndrome (Cowden's disease) exhibiting characteristic cutaneous lesions and involvement of several inner organs.

Unscheduled DNA synthesis in normal human skin after single and combined doses of UV-A, UV-B and UV-A with methoxsalen (PUVA)

The aim of this study was to measure unscheduled DNA synthesis (UDS) by autoradiography in normal human skin (I) after high dose UV-A, (2) after low dose UV-A applied before or after erythemogenic doses of UV-B, (3) after high dose PUVA and (4) after therapeutic doses of PUVA applied before and after erythemogenic doses of UV-B. Single high dose UV-A exposure induced roughly 60% of the amount of UDS induced by equally erythemogenic doses of UV-B. Single low dose UV-A exposure did not induce UDS, nor did it significantly alter the amount of UV-B induced UDS when combined with UV-B exposure. Single high dose PUVA did not lead to UDS and had no influence on UV-B induced UDS when combined with UV-B exposure. Our findings indicate: (I) erythemogenic doses of UV-A induce a considerable DNA excision repair; (2) low dose UV-A neither augments UV-B induced DNA repair nor does it inhibit the repair process; (3) no UDS was shown to occur after eight high or therapeutic doses of PUVA. This was unexpected since psoralen-DNA monoadducts have been shown to be repairable by a mechanism similar to excision repair of pyrimidine dimers. It is therefore assumed that PUVA as performed for therapeutic purposes either preferentially induced interstrand crosslinks not repairable via the classical repair mechanism or the repair of monoadducts was below resolution in this study; (4) therapeutic PUVA doses apparently do not interfere with excision repair of UV-B induced DNA lesions.

3H-thymidine autoradiography of guinea pig cornea and skin after exposure to solar simulating radiation

In vitro autoradiography with tritiated thymidine was performed in guinea pig cornea and guinea pig skin after in vitro exposure to solar simulating radiation (UVB). UVA-irradiated and unirradiated specimens served as controls. Sparsely labelled nuclei, indicating the unscheduled thymine dimer repair DNA-synthesis (dark repair), were observed immediately after UVB exposure in the epidermis and upper dermis of the skin and in all cellular compartments of the cornea. Control samples did not exhibit dark repair. The ratio of sparsely labelled cells was similar in the epidermis and in the corneal epithelium, but was significantly higher in the corneal stroma and highest in the endothelium.

[An unusual case of repeated self mutilation (author's transl)]

An unusual case is presented of repeated, life-threatening self mutilation, elicited by the topical application of sodium hydroxide, which necessitated several operations, including amputation of the left lower leg. Histological examination revealed colliquation necrosis and a striking eosinophilia. The latter feature, which was not reproducible in an animal experiment, may be related to a defect of leucocyte locomotion in the present case.