[Insertional Achilles tendinopathy : Differentiated diagnostics and therapy]. / Ansatznahe Erkrankungen der Achillessehne : Differenzierte Diagnostik und Therapie.

Achilles tendinopathy at the calcaneal insertion is classified into insertional tendinopathy, retrocalcaneal and superficial bursitis. The aim of this study was to present the current evidence on conservative and surgical treatment of insertional tendinopathy of the Achilles tendon. Conservative first-line therapy includes reduction of activity levels, administration of non-steroidal anti-inflammatory drugs (NSAID), adaptation of footwear, heel wedges and orthoses or immobilization. In addition, further conservative therapy options are also available. Eccentric stretching exercises should be integral components of physiotherapy and can achieve a 40% reduction in pain. Extracorporeal shock wave therapy has been shown to reduce pain by 60% with a patient satisfaction of 80%. Due to the limited evidence, injections with platelet-rich plasma (PRP), dextrose (prolotherapy) or polidocanol (sclerotherapy) cannot currently be recommended. Operative therapy is indicated after 6 months of unsuccessful conservative therapy. Open debridement allows all pathologies to be addressed, including osseous abnormalities and intratendinous necrosis. The success rate of over 70% is contrasted by complication rates of up to 40%. The Achilles tendon should be reattached, if detached by >50%. No valid data are available for the transfer of the tendon of the flexor hallucis longus (FHL) muscle but it is frequently applied in cases of more than 50% debridement of the diameter of the Achilles tendon. Lengthening of the gastrocnemius muscle cannot be recommended because insufficient data are available. Tendoscopy is a promising treatment option for isolated retrocalcaneal bursitis and has shown similar success rates to open debridement with significantly lower complication rates.

MR-guided laser-induced thermotherapy (LITT) in patients with liver metastases of uveal melanoma.

PURPOSE: Evaluation of the local tumour control rate and survival data for magnetic resonance (MR) imaging-guided laser ablation of uveal malignant melanoma liver metastases by using laser-induced interstitial thermotherapy (LITT). MATERIALS AND METHODS: The LITT was performed in 18 patients with liver metastases (n = 44) from uveal malignant melanoma. All patients tolerated this intervention well. With the Kaplan-Meier method, the survival rates were calculated. Indications for the procedure were defined for patients with no more than five metastases, none of which were larger than 5 cm in diameter: The Indication for LITT treatment were recurrent liver metastases after partial liver resection (22%), locally non-resectable tumours (17%) or metastases in both liver lobes (61%). RESULTS: The mean survival rate for all treated patients was 3.6 years (95% CI: 2.19, 5.06). We started the calculation on the date of diagnosis of the metastases treated with LITT. The median survival was 1.83 years; 1-year survival, 88%; 3-year survival 47%, 5-year survival 17%. Calculated after the first LITT treatment the median survival was 2.8 years (95% CI: 1.0, 5.0). 10 patients were treated by transarterial chemoembolization before LITT. CONCLUSION: MR-guided LITT treatment shows a high local tumour control and survival rates in patients with liver metastases of uveal malignant melanoma.

A direct test of nitrogen and phosphorus limitation to net primary productivity in a lowland tropical wet forest.

Experimental evidence for limitation of net primary productivity (NPP) by nitrogen (N) or phosphorus (P) in lowland tropical forests is rare, and the results from the few existing studies have been inconclusive. To directly test if N or P limit NPP in a lowland tropical wet forest in Costa Rica, we conducted a full factorial fertilization experiment (4 treatments x 6 replicates in 30 x 30 m plots). We focused on the influence of tree size and taxa on nutrient limitation, because in these forests a wide variety of tree functional traits related to nutrient acquisition and use are likely to regulate biogeochemical processes. After 2.7 years, a higher percentage of trees per plot increased basal area (BA) with P additions (66.45% +/- 3.28% without P vs. 76.88% +/- 3.28% with P), but there were no other community-level responses to N or P additions on BA increase, litterfall productivity, or root growth. Phosphorus additions resulted in doubled stem growth rates in small trees (5-10 cm diameter at breast height (dbh); [P < or = 0.01]) but had no effect on intermediate (10-30 cm dbh) or large trees (> 30 cm dbh). Phosphorus additions also increased the percentage of seedling survival from 59% to 78% (P < 0.01), as well as the percentage of seedlings that grew (P = 0.03), and increased leaf number (P = 0.02). Trees from Pentaclethra macroloba, the most abundant species, did not increase growth rates with fertilization (P = 0.40). In contrast, the most abundant palms (Socratea exorrhiza) had more than two times higher stem growth rates with P additions (P = 0.01). Our experiment reiterates that P availability is a significant driver of plant processes in these systems, but highlights the importance of considering different aspects of the plant community when making predictions concerning nutrient limitation. We postulate that in diverse, lowland tropical forests "heterogeneous nutrient limitation" occurs, not only driven by variability in nutrient responses among taxa, but also among size classes and potential functional groups. Heterogeneous responses to nutrient additions could lead to changes in forest structure or even diversity in the long-term, affecting rates of NPP and thus carbon cycling.

Repeated transarterial chemoembolisation using different chemotherapeutic drug combinations followed by MR-guided laser-induced thermotherapy in patients with liver metastases of colorectal carcinoma.

BACKGROUND: To evaluate a treatment protocol with repeated transarterial-chemoembolisation (TACE) downsizing before MR-guided laser-induced interstitial thermotherapy (LITT) using different chemotherapeutic combinations in patients with unresectable colorectal cancer (CRC) liver metastases. METHODS: Two hundred and twenty-four patients were included in the current study. Transarterial-chemoembolisation (mean 3.4 sessions per patient) was performed as a downsizing treatment to meet the LITT requirements (number5, diameter <5 cm). The intra-arterial protocol consisted of either Irinotecan and Mitomycin (n=77), Gemcitabine and Mitomycin (n=49) or Mitomycin alone (n=98) in addition to Lipiodol and Embocept in all patients. Post TACE, all patients underwent LITT (mean 2.2 sessions per patient). RESULTS: Overall, TACE resulted in a mean reduction in diameter of the target lesions of 21.4%. The median time to progression was 8 months, calculated from the start of therapy and the median local tumour control rate was 7.5 months, calculated as of therapy completion. Median survival of patients calculated from the beginning of TACE was 23 months (range 4-110 months), in patients treated with Irinotecan and Mitomycin the median was 22.5 months, Gemcitabine and Mitomycin 23 months and Mitomycin only 24 months with a statistically significant difference between the groups (P<0.01). CONCLUSION: Repeated TACE offers adequate downsizing of CRC liver metastases to allow further treatment with LITT. The combined treatment illustrates substantial survival rates and high local tumour control with statistically significant differences between the three protocols used. Further randomised trials addressing the current study results are required.

[Chemoperfusion and embolization in the treatment of liver metastases]. / Chemoperfusion und -embolisation von Lebermetastasen.

Presentation of techniques and procedures for regional chemotherapy in the treatment of unresectable liver metastases from different primary tumors as a modality of interdisciplinary therapy management. Such transarterial therapy methods include hepatic arterial infusion (HAI), transarterial chemoembolization (TACE), chemoembolization with cytostatic-loaded microspheres (DEBs), transarterial embolization (TAE) and selective internal radiation therapy (SIRT). Regional chemotherapy procedures in the treatment of liver metastases represent a minimally invasive treatment option that can be successfully combined with surgical resection and/or radiofrequency (RFA), laser-induced thermotherapy (LITT), microwave ablation (MWA). These procedures allow optimization of the local control rate with strictly intrahepatic processes and lead to increased survival rates without any quality of life restriction.

[MR-guided interventions of the prostate gland: a literature review]. / Aktueller Stand der MR-gesteuerten Prostata-Interventionen.

In recent years MR imaging has played an increasingly important role in the diagnosis and treatment of prostate cancer. MR imaging of the prostate allows clear delineation of the anatomic structures and prostate tumors using T 2-weighted images combined with spectroscopy and dynamic examinations. The advantages of MRI make it possible to perform interventions, like biopsies, brachytherapy or different local therapies of the prostate gland. MRI robotic assistance will improve the accuracy of the interventions. Due to the advantages of MR imaging, MR-guided prostate interventions will play a greater role in the future.

Regulation of desaturase expression in HL60 cells.

The expression of delta 5 desaturase (D5D), delta 6 desaturase (D6D) and delta 9 desaturase (D9D) was determined by RT-PCR in the human promyelocytic cell line HL60. During 72 h of culture with 10% FBS, D5D and D6D were upregulated 5 to 6-fold, whereas D9D approximately doubled. The addition of fatty acids (FAs) to the culture medium suppressed upregulation of all desaturases. N-3 and n-6 FA appeared to be more effective than n-9 or saturated FA. When FAs were added after 72 h, further upregulation during the next 24 h was suppressed for nearly all desaturases and FAs tested, except for D5D when oleic acid (OA) or stearic acid (SA) was added. In cells cultured with restricted amounts of FBS, desaturase expression increased with decreasing concentrations of FBS. Cellular FA content decreased by 60% in the neutral lipid fraction, whereas that of the phospholipid fraction decreased by 10% during 72 h of culture. The largest decrease occurred in the sum of n-3 and n-6 FA of the neutral lipid fraction, which was reduced by 83%, whereas the content of these FAs in the phospholipid fraction decreased by 32%. The results indicate that when the supply of FA to HL60 cells is limited, the intracellular content of n-3 and n-6 FA decreases and this leads to upregulation of the desaturases, particularly D5D and D6D. Since HL60 cells resemble human leukocytes, the results suggest that desaturase expression in leukocytes may be exploited as a biomarker for FA status.

[MR thermometry for laser-induced thermotherapy at 1.5 Tesla]. / MR-Thermometrie bei 1,5 Tesla zur thermischen Ablation mittels laserinduzierter Thermotherapie.

PURPOSE: Evaluation of thermometry with fast MR sequences for laser-induced interstitial laser therapy (LITT) and verification of the thermometric results with a fiber-optic thermometer. METHOD AND MATERIALS: In vitro experiments were conducted using an agarose gel mixture and pig liver lobes. MR-guided LITT was performed using a laser power between 3 and 15 watts. Thermometry was performed using longitudinal relaxation time T1 and proton resonance frequency shift (PRF) methods under acquisition of amplitude and phase shift images. PRF was measured with a fast spoiled GRE sequence. Four different sequences were used for T1 thermometry: gradient echo (GE), TrueFISP (TRUFI), Saturation Recovery Turbo-FLASH (SRTF) and Inversion Recovery Turbo-FLASH (IRTF) sequences. The temperature was controlled using a fiber-optic Luxtron device and correlated with the MR temperature. The range of applied and monitored temperatures exceeded 80 degrees Celsius. RESULTS: The temperature dependence showed a good linear relationship up to 60 degrees Celsius. Calibration experiments for the T1 method delivered coefficients of determination from 0.977 to 0.997 for agarose and from 0.958 to 0.995 for the pig liver samples. The IRTF sequence had the highest temperature sensitivity (agarose 0.99, liver 1.19). During LITT the TRUE-FISP sequence exhibited a strong nonlinear relationship. R (2) of this sequence was 0.809 in the agarose experiments. The average temperature errors when heated up to 80 degrees Celsius were 3.86-11.38 degrees Celsius for Agarose gel and 5.7-12.16 degrees Celsius for the liver tissue. SRTF and IRTF sequences exhibited the most linear relationship with temperature but were more dependent on tissue differences. CONCLUSION: The accuracy of the temperature measurement is sufficient for controlling the coagulation area of the LITT. PRF is the method of choice since it shows the best linear correlation with fiber-optic temperature. If only T1 sequences are concerned, the FLASH sequence is preferred. It is the most robust, though not the most accurate, T1 sequence.

[Nucleolysis in the herniated disk]. / Nukleolyse beim Bandscheibenvorfall.

Back pain associated with a herniated disk has become an important and increasing general health problem in Germany and other industrialized countries. After all methods of conservative treatment have been exhausted, nucleolysis may be a minimally invasive alternative to surgery. In nucleolysis, chondrolytic substances or other substances, which reduce the pressure within the disk by other means, are injected into the nucleus pulposus under CT guidance. Among various substances, which have been employed for nucleolysis, an ozone-oxygen mixture appears to be very promising. The water-binding capacity of ozone results in a reduction of pain for several months. Moreover, it has an anti-inflammatory effect and results in an increase of perfusion. Ozone is converted into pure oxygen in the body and has a low allergic potential. Recent minimally invasive therapeutic methods such as percutaneous nucleotomy or laser treatment do not result in superior results compared with nucleolysis.

[Variation in X-ray dose quantity using an amorphous selenium based flat-panel detector -- a study on the dose reduction rate up to the limit of diagnostical utilization]. / Dosisvariation mit einem direkten Selen-Flachbilddetektor -- Eine Studie zur Dosisreduktion bis an die Grenzen der diagnostischen Verwertbarkeit.

PURPOSE: To evaluate the diagnostic quality and minimum required dose to obtain acceptable images for diagnostic purposes in the field of musculoskeletal radiology. MATERIALS AND METHODS: A critical comparison of the image quality produced by a novel flat panel detector and the conventional screen/film system using a contrast-detail phantom was performed in phase I. Images from both systems were obtained with the same dose and displayed with similar contrast and density. In phase II images of significant anatomical structures in cadaver extremities obtained using the digital detector system and the standard film/screen system were critically evaluated. After a successive reduction in the X-ray dose for 84 patients in phase III, eight independent radiologists compared the image quality of the screen/film system to that of the novel flat panel detector. RESULTS: Phases I and II revealed a difference in the image quality achieved by the standard screen/film system and the digital detector system to the advantage of the digital detector system. In 77 of 84 patients (91.7 %), phase III showed equal image quality after a 50 % reduction in the X-ray dose. In 3 cases (3.6 %) the image quality and the level of contrast were better. No unified statement could be made for 4 patients (4.7 %). CONCLUSION: Digital imaging of skeletal disorders using the novel flat panel detector makes it possible to reduce the X-ray dose by 50 % with equal or even better image quality.

[Laser-induced Interstitial thermotherapy (LITT) in hepatic metastases of various sizes in an animal model]. / Laserinduzierte interstitielle Thermotherapie (LITT) von Lebermetastasen unterschiedlicher Grösse im Kleintiermodell.

PURPOSE: To assess the effect of laser-induced thermotherapy (LITT) on liver metastases of various size from colon carcinoma in an animal model. MATERIALS AND METHODS: Liver metastases were implanted in 20 Wistar Albino Glaxo (WAG) rats by subcapsular injection of cells from a colorectal strain (CC531) (day 0). The animals were divided into two groups with regard to the measured tumor size of 0.05 - 0.06 cm (3) (group A) and 0.10 - 0.12 cm (3) (group B). On day 14 after laparotomy, the tumors were exposed to 1064 nm Nd:YAG laser light at 2 watts for 5 minutes after intratumoral placement of the laser applicator set. The tumor volumes before (V1, at day 13) and after treatment (V2, at day 28) were determined by MRI and the mean tumor growth ratio (V2/V1) was calculated. RESULTS: The mean tumor volumes V1 and V2 were 0.05 +/- 0.003 cm (3) and 0.23 +/- 0.016 cm (3) in group A, and 0.11 +/- 0.006 cm (3) and 0.68 +/- 0.037 cm (3) in group B. The mean tumor growth ratio (V2/V1) was 4.31 +/- 0.19 in group A and 6.11 +/- 0.14 in group B. The mean volume of the induced necrosis (0.15 +/- 0.01 cm (3)) was the same for both groups ( p > 0.05). Compared to group B, liver metastases of group A showed a significant slower tumor growth velocity (paired t-test, p < 0.0001). CONCLUSION: The interventional treatment of large hepatic tumors with LITT leads to faster tumor growth compared to smaller lesions.

[Percutaneous thermoablation of pulmonary metastases. Experience with the application of laser-induced thermotherapy (LITT) and radiofrequency ablation (RFA), and a literature review]. / Perkutane Thermoablation von Lungenmetastasen - Erfahrungen mit dem Einsatz der LITT, der Radiofrequenzablation (RFA) und Literaturübersicht.

PURPOSE: Evaluation of technical aspects, local efficiency and complications of thermoablative procedures, such as radiofrequency ablation (RFA) and laser-induced thermotherapy (LITT), in percutaneous lung metastases. MATERIALS AND METHODS: Techniques of thermal ablative procedures of RFA and LITT are presented. For primary positioning, monitoring and therapy control, computed tomography (CT) or magnetic resonance imaging (MRI) was performed. Different monopolar systems and one bipolar system were available for RFA and two different cooling systems for LITT. Percutaneous CT-guided RFA was performed on 32 metastases in 20 patients and percutaneous LITT on 34 metastases in 24 patients. Inclusion criteria were metastases < or = 5 cm in diameter in unresectable patients with up to 3 metastases per lung. All treatments were performed on outpatient basis using analgosedation. RESULTS: In our patient group, all patients tolerated both the RFA and LITT procedures well with mild sedation. The pneumothorax rate was 15 % (5/32 procedures) for the RFA group and 12 % (4/34 procedures) for the LITT group, without insertion of a chest tube. In all RF ablations, a complete "roll off" (increase in impedance) was achieved. Local tumor control rate in the 6-month follow-up was 85 % for RFA and 91 % for LITT. Nineteen of the 20 patients treated are still alive, one patient died from tumor progression. CONCLUSION: Both pulmonary RFA and LITT allow safe thermal ablation of pulmon arg metastases with a low complication rate and an acceptable tumor control rate.

[Laser-induced thermotherapy of lung metastases and primary lung tumors]. / Laserinduzierte Thermotherapie von Lungenmetastasen und primären Lungentumoren.

We present laser-induced thermotherapy (LITT) of primary and secondary lung tumors analysing indications and technical concepts. Thirty patients with lung metastases of different primary tumors (n=24) as well as localized lung tumors (n=6) were prospectively treated in 41 sessions using laser-induced thermotherapy (LITT). An MR-compatible puncture system was used with direct puncture technique. The puncture was performed via CT guidance in care vision technique. Eight patients were thermoablated using MR tomographical monitoring, 22 patients using CT monitoring. Local therapy effects, tumor control rate, side effects, complications, and survival were evaluated. In 74% of cases (28/38 lesions) of 24 patients with lung metastases and in all cases of the 6 patients with lung carcinoma a complete local ablation could be achieved. The complication rate (pneumothorax) was 9,8%. One patient with bronchial carcinoma had to be thoracotomized and resected. 93% of the patients are still alive. Percutaneous LITT of lung tumors permits a complete ablation of lung metastases and lung carcinomas with a low complication rate. Indications for the procedure were defined for patients with no more than 5 metastases up to 3 cm in size.

MR-guided laser-induced thermotherapy (LITT) of liver tumours: experimental and clinical data.

MR-guided laser-induced interstitial thermotherapy (LITT) is a percutaneous, minimally invasive treatment modality for treating liver lesions/metastases, soft tissue tumours and musculoskeletal lesions. In this group, MR-guided LITT is currently performed under local anaesthesia on an out-patient basis with a specially designed saline-cooled laser application system. Nd:YAG laser (1064 nm wave length) was used for tumour ablation. Magnetic resonance imaging (MRI) using both open and closed MR units has proven clinically effective in validating the exact positioning of optical fibres. It also allows for real time-monitoring of thermal effects and the evaluation of treatment-induced coagulation necrosis. In liver tumours, percutaneous MR-guided LITT achieves a local tumour control rate of 98.7% at 3 months post-therapy and 97.3% at 6 months with metastases smaller than 5 cm in diameter. The mean survival rate for 1259 patients with 3440 metastases treated with 14 694 laser applications at the institute (calculated with the Kaplan-Meier method) was 4.4 years (95% confidence interval: 4.1-4.8 years) and median survival was 3.00 years. No statistically significant difference in survival rates was observed in patients with liver metastases from colorectal cancer vs metastases from other primary tumours. The rate of clinically relevant side effects and complications requiring secondary treatment was 2.2%. The clinical use of MR guided LITT (size < 5 cm, number < 5) is justified in patients with liver metastases of colorectal and/or breast cancers if the inclusion criteria are carefully observed. Further indications for MR guided LITT include recurrent cancer lesions in the head and neck, lung metastases and bone and soft tissue lesions.

[Hepatocellular carcinoma: Role of imaging diagnostics in detection, intervention and follow-up]. / Das hepatozelluläre Karzinom. Rolle der Bildgebung zur Detektion, Therapieplanung und Therapiekontrolle.

PURPOSE: Demonstration of techniques and clinical value of imaging diagnostics for screening, detection, interventional follow-up and therapy control of hepatocellular carcinoma (HCC). Diagnostic techniques for screening, detection and differential diagnosis of HCC are presented using color-coded duplex sonography (US), computer tomography (CT) and contrast-enhanced magnetic resonance techniques like MRI, MR angiography and MR cholangiopancreaticography (MRCP). Therapy control with imaging was performed for surgical methods like resection and liver transplantation as for well as transarterial chemoembolization (TACE), radiofrequency ablation (RF) and laser-induced thermotherapy (LITT). In screening, HCC color-coded duplex sonography reveals a sensitivity from 45 to 92 % and a specificity from 78 to 90 % when liver cirrhosis is present. The diagnostic results of CT were further improved with the newly developed techniques of multislice CT. The highest diagnostic accuracy can currently be achieved using contrast-enhanced MRI with a sensitivity from 82 to 96 %. TACE presents a palliative therapy concept; MR-guided LITT and radiofrequency ablation are used as thermoablative methods for local therapy and the therapy control is based on the above imaging techniques. Contrast-enhanced MRI proves to be the superior imaging technique for the early diagnosis, differential diagnosis and follow-up of hepatocellular carcinoma.

[Transarterial chemoembolization of liver metastases: Indication, technique, results]. / Transarterielle Chemoembolisation von Lebermetastasen: Indikationsstellung, Technik, Ergebnisse.

We have analyzed the effectiveness of repetitive transarterial chemoembolization (TACE) of liver metastases as a neoadjuvant or palliative treatment modality in comparison with published data. Chemoembolization of liver metastases is performed with different cytotoxic drugs. In a 4-week interval, 357 patients were treated with repetitive 1,158 TACE courses performed with lipiodol, mitomycin C and spherex. 254 patients were treated palliatively, 18 patients symptomatically and 79 patients via the neoadjuvant protocol, 71 patients of whom received additional MR-guided laser-induced thermoablation (LITT) of the metastases after TACE. Our results were compared with the literature. Most of the patients with a low rate of local complications like vascular occlusion or liver abscess could be treated successfully using TACE. In 81 % of the treated lesions a primary high lipiodol retention was observed. In the palliative group a reduction of the tumor size was noted in 36 % of the lesions, a growth stop in 24 % and a reduction of the tumor growth rate in 40 %. In 70 % of the patients treated neodadjuvantly a reduction of the tumor size was found. The median survival rate of our collective of patients with liver metastases averages 8.6 months. In the literature median survival rates in patients with liver metastases were between 8.5 and 23 months after TACE. TACE is judged as a minimal invasive and outpatient treatment protocol for liver metastases. A combination of TACE and different local treatment modalities presents a neoadjuvant treatment strategy to control the diseased liver.

MR-guided laser-induced thermotherapy in recurrent extrahepatic abdominal tumors.

The aim of this study was to evaluate the feasibility of MR-guided laser-induced thermotherapy (LITT) for treatment of recurrent extrahepatic abdominal tumors. In 11 patients (6 women and 5 men; mean age 53 years, age range 29-67 years) with 14 lesions the following tumors were treated in this study: paravertebral recurrence of hypernephroma (n=1); recurrence of uterus carcinoma (n=1); recurrence of chondrosarcoma of the pubic bone (n=1); presacral recurrence of rectal carcinoma (n=1); recurrent anal cancer (n=1); metastases in the abdominal wall (n=1); and lymph node metastases from colorectal cancer (n=8). A total of 27 laser applications were performed. A fast low-angle shot 2D sequence (TR/TE/flip angle=102 ms/8 ms/70 degrees ) was used for nearly real-time monitoring during treatment. All patients had no other treatment option. Seventeen LITT sessions were performed using a conventional laser system with a mean laser power of 5.2 W (range 4.5-5.7 W), and 10 LITT session were performed using a power laser system with a mean laser power of 28.0 W. In 10 lesions total destruction could be achieved. In the remaining recurrent tumors, significant reduction of tumor volume by 60-80% was obtained. All patients tolerated the procedure well under local anesthesia. No complications occurred during treatment. Laser-induced thermotherapy is a practicable, minimally invasive, well-tolerated technique that can produce large areas of necrosis within recurrent tumors, substantially reducing active tumor volume if not resulting in outright destruction of tumor.

[Transarterial chemoembolization in hepatocellular carcinomas: technique, indications, results]. / Transarterielle Chemoembolisation bei hepatozellulären Karzinomen: Technik, Indikationsstellung, Ergebnisse.

BACKGROUND: At time of diagnosis 80% of the patients with hepatocellular carcinoma (HCC) could not be treated with surgical treatments, so that transarterial chemoembolization (TACE) was used as an neoadjuvant or palliative treatment modality. MATERIAL AND METHODS: 60 patients were treated with 217 TACE courses, in the mean 3.6 TACE treatments per patient with an 4 week interval. TACE was performed with a dispersion of lipiodol, mitomycin C and spherex. 11 patients (18.3%) were treated in a neoadjuvant protocol with successful ablation. Lipiodol retention and size of the tumors were evaluated by CT and MRI. RESULTS: 60 patients were successful treated with TACE. After treatment a primary high lipiodol retention was displayed and in 68 (63.3%) patients a reduction of the tumor size and in 11 (20%) patients a reduction of tumor growth rate was noted. The 1 year survival rate was 59%. After response to TACE and reducing the tumor size 11 patients could be treated with MR-guided LITT 4 to 6 weeks post embolization. CONCLUSION: Chemoembolization is a minimal invasive and outpatient treatment protocol for HCC. TACE might be indicated as a palliative treatment to control the diseased liver. If repeated TACE alters the size and structure of primary unresectable HCC TACE expands the indication for MR-guided LITT.

[Oligonodular hepatocellular carcinoma (HCC): MR-controlled laser-induced thermotherapy]. / Oligonoduläres hepatozelluläres Karzinom (HCC): MR-gesteuerte laserinduzierte Thermotherapie (LITT).

PURPOSE: To prospectively evaluate the therapeutic potential of MR-guided laser-induced thermotherapy (LITT) in patients with oligonodular hepatocellular carcinoma. MATERIAL AND METHODS: 39 patients with 61 intrahepatic lesions were treated with LITT. The Nd:YAG laser fiber was introduced with a percutaneously positioned irrigated laser application system. Qualitative and quantitative MR parameters and clinical data were evaluated. RESULTS: All patients tolerated the procedure well under local anesthesia. All observed complications were minor and no further treatment was necessary. Online MR thermometry allowed exact visualization. Lesions up to 2 cm in diameter could be efficiently treated with a single laser application, larger lesions were treated simultaneous multiapplication. In 97.5% we achieved a complete necrosis of the tumor and a 5 mm safety margin, resulting in a complete destruction of the tumor without local recurrences. Mean survival was 4.4 years (95% CI: 3.6-5.2 years) after the time of diagnoses of the HCC (Kaplan-Meier-method). CONCLUSION: In intrahepatic oligonodular involvement of hepatocellular carcinoma LITT appears to be an effective therapeutic procedure with a high tumor control rate and better survival data.

Percutaneous MR imaging-guided laser-induced thermotherapy of hepatic metastases.

BACKGROUND: Many primary tumors may cause liver metastases, which are generally treated with surgical resection and/or chemotherapy. After resection of liver metastases in patients with colorectal carcinoma, 5-year survival rates are achieved in 25-38%, and two-thirds of patients will experience recurrent metastases. We examined percutaneous, minimally invasive, laser-induced thermotherapy (LITT) as an alternative outpatient procedure. Local tumor control rate and survival data were analyzed prospectively. METHODS: Between June 1993 and August 2000, 7148 laser applications were performed in 1981 lesions in 705 consecutive patients and 1653 treatment sessions. The complications of the procedure were evaluated by clinical examination and magnetic resonance imaging (MRI) and computed tomography. Local tumor control was evaluated by plain and contrast-enhanced follow-up MRI using T1- and T2-weighted spin-echo and gradient-echo sequences every 3 months after treatment. Cumulative survival times were calculated using the Kaplan-Meier method. RESULTS: The overall rate of complications and side effects was 7.5%. The rate of clinically relevant complications was 1.3%. Local tumor control rate after 3 months was 99.3%; 6 months after laser treatment, plain and contrast-enhanced MRI documented a local tumor control rate of 97.9%. In patients treated with MR-guided LITT for unresectable colorectal liver metastases, the mean survival was 41.8 months (95% confidence interval = 37.3-46.4 months). The 1-year survival rate was 93%, the 2-year survival rate was 74%, the 3-year survival rate was 50%, and the 5-year survival was 30%. In patients treated with LITT for liver metastases from breast cancer, the mean survival was 4.3 years (95% confidence interval = 3.6-5.0 years). CONCLUSION: In patients with liver metastases, local tumor destruction using minimally invasive, percutaneous LITT under local anesthesia results in improved clinical outcomes and survival rates and can be a potential alternative to surgical resection.