[Chemoperfusion and embolization in the treatment of liver metastases]

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]

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.

Perfusion CT in squamous cell carcinoma of the upper aerodigestive tract: long-term predictive value of baseline perfusion CT measurements

BACKGROUND AND PURPOSE

PCT studies hold short-term predictive value in patients treated with chemoradiotherapy. Our aim was to examine the long-term predictive value of baseline PCT studies for local tumor control and overall survival in SCCA of the upper aerodigestive tract treated with chemoradiotherapy.

MATERIALS AND METHODS

Eighty-four patients with advanced SCCA underwent PCT followed by concomitant chemoradiation. The acquired perfusion maps represented BF, BV, MTT, and PS. Visual analysis of the parametric maps for identification of tumor perfusion patterns was conducted. ROC curves, t tests, and Kaplan-Meier survival curves were plotted for local disease control and overall survival.

RESULTS

The median time of local tumor control was 24 months. The BF and PS values were significantly higher in patients who had no recurrence than in those with local failure (P < or = .02). The BF and PS were predictive (P < or = .0006) but BV and MTT held no significant predictive values for local tumor control. The patients with high BF and PS had a longer local tumor control than the patients with hypoperfused tumors (P = .0007). A visually detected BF-BV mismatch had a sensitivity/specificity of 63%/66% (P = .03) and 59%/69% (P = .03) for local tumor control and OS, respectively. Patients without mismatch lived significantly longer than patients with mismatch (P = .01).

CONCLUSIONS

BF, PS, and mismatch of BF-BV are significant predictors of local tumor control after chemoradiation in SCCA of the upper aerodigestive tract.

Response and progression-free survival in oropharynx squamous cell carcinoma assessed by pretreatment perfusion CT: comparison with tumor volume measurements

BACKGROUND AND PURPOSE

Perfusion CT (PCT) provides a rapid, reliable, and non-invasive technique for assessing tumor vascularity. The purpose of this study was to assess whether pretreatment dynamic perfusion CT (PCT) may predict response to induction chemotherapy and midterm progression-free survival (PFS) in advanced oropharynx squamous cell carcinoma (SCCA) and to compare the results with those derived by tumor volume measurements.

MATERIALS AND METHODS

Nineteen patients underwent routine contrast-enhanced CT (CECT), pretreatment PCT, and conventional endoscopy. Tumor response was determined according to radiologic (RECIST) criteria. The PCT parameters, tumor volume, radiologic response, and PFS were analyzed with use of Cox-proportional hazards model, receiver operating characteristic (ROC), and Kaplan-Meier analysis.

RESULTS

The baseline blood flow (BF), blood volume (BV), and permeability surface area product (PS) were significantly higher, whereas mean transit time (MTT) was significantly lower in the responders than in the nonresponders (P < or = .002). BV showed 100% sensitivity, MTT and PS had the highest specificity (100%), and BF showed 84.2% sensitivity and 66.7% specificity for prediction of tumor response after induction chemotherapy. The pretreatment tumor volume correlated with PFS in the pooled patients group (r = 0.4; P < .0001), whereas postinduction tumor volume correlated significantly with PFS in the responders and nonresponders (r = 0.22-0.64; P < or = .006). Pretreatment tumor volume (P = .0001) and BF (P = .001) were significant predictors for PFS.

CONCLUSIONS

Pretreatment PCT parameters may predict response after induction chemotherapy. Tumor volume and BF values may predict PFS in patients with advanced oropharyngeal SCCA.

Radiofrequency ablation of experimental bone metastases in nude rats

PURPOSE

Animal models are indispensable to investigate bone metastasis and to test different preclinical therapy options. Radiofrequency ablation is an upcoming technique for palliating pain from bone metastases. The aim of this study was to generate osteolytic lesions and to enable a technique to achieve access to the bone to successfully carry out radiofrequency ablation.

MATERIALS AND METHODS

Human breast cancer cell line MDA-MB-231 (10(5) tumor cells) was implanted into the femur of 10 nude rats using a drill hole after arthrotomy of the knee joint and opening of the femur through the notch. Weekly CT- and MRI-scans were performed to document number and size of bone metastases. Radiofrequency ablation (22G bipolar and impedance-controlled RF-applicator, 2-4 Watt, 3 min application time) was carried out. One week after RFA, the animals were sacrificed and macroscopic and histological examination followed. For statistical analysis, paired comparison procedures were used.

RESULTS

Inoculation of the tumor cells was well tolerated. The mean time of the surgical procedure was 6 minutes. All animals developped local bone metastases. Mean time to metastasis was 8 weeks (range 7-10 weeks) after tumor cell implantation. No leakage of tumor cells and no soft part metastases occurred. Radiofrequency ablation was performed without complications. Imaging showed a complete ablation of the bone tumor in all rats. Histological findings confirmed a circular necrosis with an extensive destruction of tumor cells leaving a necrosis cavity.

CONCLUSION

The experimental model presented here describes the first time the ability to carry out radiofrequency ablation in nude rats with intrafemoral induced osteolytic metastases of human breast cancer. RFA in human breast cancer cell line in nude rats is a feasible and useful possibility to evaluate and to test different RF-procedures. Additional treatment options like local chemotherapy or chemoembolization can be performed.

MR-guided interventions of the prostate gland

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 a clear delineation of the anatomic structures and prostate tumors when performing interventions such as biopsies, brachytherapy or thermal therapy 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 an increasing role in future.