Reducing contrast medium volume and tube voltage in CT angiography of the pulmonary artery.

AIM: To evaluate image quality after contrast medium (CM) and tube voltage reduction in computed tomography angiography (CTA) of the pulmonary artery. MATERIALS AND METHODS: Thirty-three patients referred for CTA of the pulmonary artery for suspected pulmonary embolism were included. Patients were randomly assigned to Protocol I (100 ml of 350 mg iodine/ml iodinated CM; n=16) or Protocol II (50 ml of 350 mg iodine/ml iodinated CM; n=17). Dual-energy CT (80 kV and 140 kV) was performed in all patients. An averaged weighted series equivalent to a 120 kV image acquisition was reconstructed. The mean attenuation value of CM was measured at eight positions in the pulmonary trunk and pulmonary arteries. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Qualitative assessment of the vascular enhancement was performed independently by two experienced radiologists using a three-point scale. Mean attenuation values, image noise, CNR, and SNR of images with 50 ml CM and images with 100 ml CM were compared and mean attenuation values, image noise, CNR, and SNR in 80 kV images and 120 kV images were compared. For qualitative analysis, interobserver variability was analysed using Cohen's kappa statistics. RESULTS: The mean attenuation values in Protocol I and Protocol II were not significantly different at 80 kV (634.6±168.3 versus 537.9±146.7 HU; p=0.088) and 120 kV (482.8±127.7 versus 410.4±106.0 HU; p=0.085). The mean attenuation value at 80 kV was significantly higher than the mean attenuation value at 120 kV in Protocols I and II (p<0.001). The CNR and SNR were higher at 120 kV than at 80 kV in both protocols (p=0.000-0.019); however, there were no significant differences in the CNR and SNR between both protocols (p=0.600-0.952). Qualitative (subjective) analysis showed no statistical significant difference between Protocols I and II (p=0.524-1.000). CONCLUSION: Low tube voltage (80 kV) CTA using 50 ml CM is not inferior to CTA at 120 kV using 100 ml CM.

A non-invasive cardiac output measurement as an alternative to the test bolus technique during CT angiography.

AIM: To investigate the association between a non-invasive cardiac output (CO) measurement and the scan delay, as derived from a test bolus injection protocol. The secondary objective was to determine which factors affect the relationship between the CO and scan delay. MATERIALS AND METHODS: Fifty-five patients referred for a contrast-enhanced (thorax-)abdomen CT examination were included in this feasibility study. A test bolus examination was performed prior to the abdominal CT. During the test bolus injection, the CO of the patient was measured using a non-invasive finger-cuff measurement. Associations were analysed using linear regression analyses. Age, gender, height, weight, and blood pressure were included as potential confounders. RESULTS: Linear regression analysis showed a negative and significant association between CO and delay. The regression formula was as follows: scan delay (seconds) = 26.8-1.6 CO (l/min), with a 95% CI between -2.3 and -1.0 (p<0.001). Weight appeared to be a confounder in this relation, and gender and blood pressure were effect modifiers. There was no interaction between scan delay and age, height and weight. CONCLUSIONS: There is a negative and significant association between the non-invasive CO measurement and the CT scan delay; however, to validate these findings a larger cohort study is needed to investigate whether the non-invasively determined scan delay is as accurate as the use of a test bolus.

Feasibility of a low concentration test bolus in CT angiography.

AIM: To investigate the feasibility of using a low-concentration test bolus in abdominal aorta computed tomography (CT) angiography (CTA). MATERIALS AND METHODS: In 10 patients referred for CTA of the abdominal aorta with a body mass index (BMI) ≤28 kg/m2, a standard test bolus of 10 ml contrast medium (CM; 350 mg iodine/ml) was compared with a low-concentration test bolus (5 ml CM; 350 mg iodine/ml; 1:1 diluted with saline) in terms of time to peak enhancement (tPE) and peak enhancement (PE). RESULTS: No significant differences were found between the standard and low-concentration test bolus in terms of tPE and PE. CONCLUSIONS: A low-concentration test bolus (5 ml, 1:1 diluted with saline) is feasible in patients with a BMI ≤28 kg/m2.

Low-dose CT angiography of the abdominal aorta and reduced contrast medium volume: Assessment of image quality and radiation dose.

AIM: To determine the effect of using 80 kV tube voltage and a reduced amount of contrast medium on the image quality and radiation dose of computed tomography angiography (CTA) of the abdominal aorta. MATERIALS AND METHODS: Patients who were referred for a CTA examination of the abdominal aorta were included in this technical efficacy study. Thirty patients were divided randomly into two groups. Fifteen patients underwent a dual-energy CT (DECT) protocol (Group A). Fifteen patients were scanned with the use of an automated tube potential selection algorithm tool (Group B). In both protocols, a test bolus injection of 10 ml ioversol (350 mg iodine/ml) was used, followed by 20 ml of 1:1 saline-diluted contrast medium. Quantitative analysis comprised determination of the mean attenuation and contrast-to-noise ratio. Qualitative image analysis was performed independently by five radiologists. The estimated radiation dose in terms of CT dose index and effective dose was recorded and compared with a standard 120 kV protocol. RESULTS: In Group B, six patients underwent CTA at 80 kV, seven patients underwent CTA at 100 kV and two patients underwent CTA at 120 kV. The mean contrast-enhancement values of Group A (80 kV) and the 80 kV subgroup of Group B were 16.5% and 27.6% higher compared to the 100 kV subgroup of Group B, these differences were, however, not significant. There were no significant differences in mean image quality between groups. In patients undergoing CTA at 80 kV the effective dose decreased by up to 51.3% compared to a conventional 120 kV CTA protocol. CONCLUSIONS: The findings of this study support the hypothesis that 80 kV in CTA of the abdominal aorta can reliably be used with only 30 ml contrast medium in total and a 50% reduction in radiation dose. The overall image quality was diagnostically adequate; however, it appeared to be suboptimal in patients with a BMI above 28 kg/m(2).

Predictors of abnormal chest CT after blunt trauma: a critical appraisal of the literature.

AIM: To identify and to evaluate predictors that determine whether chest computed tomography (CT) is likely to reveal relevant injuries in adult blunt trauma patients. METHODS: After a comprehensive literature search for original studies on blunt chest injury diagnosis, two independent observers included studies on the accuracy of parameters derived from history, physical examination, or diagnostic imaging that might predict injuries at (multidetector row) CT in adults and that allowed construction of 2x2 contingency tables. For each article, methodological quality was scored and relevant predictors for injuries at CT were extracted. For each predictor, sensitivity, specificity, positive and negative likelihood ratio and diagnostic odds ratio (DOR) including 95% confidence intervals were calculated. RESULTS: Of 147 articles initially identified, the observers included 10 original studies in consensus. Abnormalities at physical examination (abnormal respiratory effort, need for assisted ventilation, reduced airentry, coma, chest wall tenderness) and pelvic fractures were significant predictors (DOR: 2.1-6.7). The presence of any injuries at conventional radiography of the chest (eight articles) was a more powerful significant predictor (DOR: 2.2-37). Abnormal chest ultrasonography (four articles) was the most accurate predictor for chest injury at CT (DOR: 491-infinite). CONCLUSION: The current literature indicates that in blunt trauma patients with abnormal physical examination, abnormal conventional radiography, or abnormal ultrasonography of the chest, CT was likely to reveal relevant chest injuries. However, there was no strong evidence to suggest that CT could be omitted in patients without these criteria, or whether these findings are beneficial for patients.

Management of hepatic trauma: a 9-year experience in 's-Hertogenbosch.

BACKGROUND: In patients who sustain abdominal trauma the liver is the most frequently injured organ. Although treatment for haemodynamically unstable patients remains urgent surgery, there has been a shift of management in haemodynamacally stable patients towards non-operative management. We performed an outcome assessment of traumatic hepatic injury. METHODS: A retrospective study was performed to assess incidence, mechanisms, management and outcome of traumatic liver injury in the region of 's-Hertogenbosch, The Netherlands, in the period 1999-2007. RESULTS: A total of 47 patients were identified. Thirty-six patients had blunt hepatic trauma, eleven sustained penetrating hepatic injury. In 67% (n = 24) of the blunt hepatic trauma patients the initial intention was to treat non-operatively. Yet, two patients underwent explorative laparotomy after one and two days. In the penetrating liver trauma patients, 91% (n = 10) underwent urgent surgery. In total, 31 of 47 patients were treated conservatively. CONCLUSION: Blunt hepatic trauma is the most common cause of hepatic trauma. Most patients sustaining hepatic trauma can be managed conservatively at a dedicated ICU and/or surgical trauma ward.

[Radio frequency ablation therapy in the elderly breast cancer patient]. / Radiofrequente ablatiebehandeling van de oudere patiënte met een mammacarcinoom.

Breast cancer is an important health care problem, especially in the increasing elderly generation. Treatment of these fragile patients is a challenge for the clinician. Undertreatment has been linked to a higher percentage of recurrence and cancer related morbidity, while overtreatment leads to treatment related morbidity and mortality. Minimally invasive techniques do offer new opportunities for patients, who are no candidates for conventional surgery. The tumor lesion is treated locally and selective with minimal damage to surrounding tissue, yielding an adequate local tumor control. Radio frequency ablation technique seems an effective and safe method for treatment of the elderly patient with small (< 3 cm) breast cancer.

[Characterisation of breast lesions with VTIQ elastography: a new elastography method to evaluate the stiffness of tissues]. / Mammatumoren karakteriseren met VTIQ-elastografie.

B-mode ultrasound is used as an adjunct to mammography to differentiate between benign and malignant breast lesions. An additional ultrasound technique is elastography which can evaluate the stiffness of tissues. It is believed that malignant lesions are generally stiffer than benign lesions. Virtual touch tissue Quantification (VTIQ) is a new elastography method for measuring the stiffness of tissue. Because this method does not depend on the degree of compression, measurements are reliable and reproducible. VTIQ - in combination with ultrasonography - has the potential to characterise abnormalities in more detail. Adding elastography to regular B-mode ultrasound improves the diagnostic specificity without loss of sensitivity. This suggests that VTIQ might change patient management and avoid unnecessary biopsies. However, further research involving a greater variety of abnormalities and larger study populations is indicated.

Magnetic resonance imaging and mammography in women with a hereditary risk of breast cancer.

BACKGROUND: Although breast cancer screening is recommended to start at a younger age for women with a hereditary risk of breast cancer, the sensitivity of mammography for these women is reduced. We compared magnetic resonance imaging (MRI) with mammography to determine which is more sensitive and whether MRI could play a role in the early detection of breast cancer for these women. METHODS: We constructed a retrospective cohort of all breast MRI and mammography surveillance reports made in our department from November 1994 to February 2001. All of the 179 women in the cohort had received biannual palpation in addition to annual imaging by MRI, mammography, or both. The 258 MRI images and the 262 mammograms were classified with the use of the BI-RADS (i.e., Breast Imaging Reporting and Data System) scoring system, which has five categories to indicate the level of suspicion of a lesion. Receiver operator characteristic curves were generated for MRI and mammography, and the area under each curve (AUC) was assessed for the entire cohort of 179 women and for a subset of 75 women who had received both an MRI and a mammographic examination within a 4-month period. All statistical tests were two-sided. RESULTS: In the cohort of 179 women, we detected 13 breast cancers. Seven cancers were not revealed by mammography, but all were detected by MRI. For the entire cohort, the AUC for mammography was 0.74 (95% confidence interval [CI] = 0.68 to 0.79), and the AUC for MRI was 0.99 (95% CI = 0.98 to 1.0). For the subset of women who had both examinations, the AUC for mammography was 0.70 (95% CI = 0.60 to 0.80), and the AUC for MRI was 0.98 (95% CI = 0.95 to 1.0). CONCLUSION: MRI was more accurate than mammography in annual breast cancer surveillance of women with a hereditary risk of breast cancer. Larger prospective studies to examine the role of MRI in screening programs are justified.

Efficacy of fluorine-18-deoxyglucose positron emission tomography in detecting tumor recurrence after local ablative therapy for liver metastases: a prospective study.

PURPOSE: The aims of this prospective study were to investigate the potential role of fluorine-18-deoxyglucose (FDG) positron emission tomography (PET) in determining the efficacy of the local tumor ablative process and to determine the added value of FDG-PET in the detection of tumor recurrence during follow-up. PATIENTS AND METHODS: Twenty-three patients with unresectable colorectal liver metastases were followed up after local ablative therapy consisting of a standard protocol including FDG-PET scanning, computed tomography (CT) scanning, and carcinoembryonic antigen measurements. The mean follow-up period was 16 months (range, 10 to 21 months). RESULTS: Ninety-six lesions was treated, 56 by local ablative treatment. Within 3 weeks after local ablative treatment, 51 lesions became photopenic on FDG-PET, while five lesions (in five patients) showed persistent activity on FDG-PET. In four of five FDG-PET-positive lesions, a local recurrence developed during follow-up; one FDG-PET-positive lesion turned out to be an abscess. None of the FDG-PET-negative lesions developed a local recurrence during a mean follow-up period of 16 months. During follow-up, 11 patients showed recurrence in the liver outside of the treated area. In all cases, previously negative FDG-PET scans became positive. Extrahepatic recurrence was encountered in nine patients during follow-up; FDG-PET showed all nine cases of tumor recurrence. There was one false-positive FDG-PET caused by an intra-abdominal abscess. In all patients, the time point of detection of recurrence by FDG-PET was considerably earlier than the detection by CT. CONCLUSION: FDG-PET seems to have a significant impact in measuring treatment efficacy directly after local ablative therapy. Furthermore, FDG-PET has an added value in patient follow-up because it reveals recurrences earlier than conventional diagnostic modalities.

Value of positron emission tomography with [F-18]fluorodeoxyglucose in patients with colorectal liver metastases: a prospective study.

PURPOSE: To assess prospectively the value of fluor-18-deoxyglucose (FDG) positron emission tomography (PET), in addition to conventional diagnostic methods (CDM), as a staging modality in candidates for resection of colorectal liver metastases. PATIENTS AND METHODS: In 51 patients analyzed for resection of colorectal liver metastases, clinical management decisions were recorded after a complete work-up with CDM. Afterward, FDG-PET scans were performed and any change of clinical management according to FDG-PET results was carefully documented. Discordances between FDG-PET and CDM results were identified and related to the final diagnosis by histopathology, intraoperative findings, and follow-up. RESULTS: In 10 (20%) out of 51 patients, clinical management decisions based on CDM were changed after FDG-PET findings were known. FDG-PET detected unresectable pulmonary (n = 5) and hepatic metastases (n = 1) and ruled out extrahepatic (n = 2) and hepatic disease (n = 2). Due to FDG-PET, eight patients were spared unwarranted liver resection or laparotomy and two other patients were identified as candidates for liver resection. When the results of FDG-PET were regarded as decisive in a retrospective analysis, potential change of management was 29% (15 patients). FDG-PET and CDM showed discordant extrahepatic results in 11 patients (22%) and discordant hepatic results in eight patients (16%). Compared with CDM, FDG-PET resulted in true upstaging (n = 11), true downstaging (n = 5), false upstaging (n = 1), and false downstaging (n = 2). The detection rate of liver metastases on a lesion basis was generally better for computed tomography than for FDG-PET (80% v 65%); this was related to tumor size. CONCLUSION: FDG-PET as a complementary staging method improves the therapeutic management of patients with colorectal liver metastases, especially by detecting unsuspected extrahepatic disease.

High prevalence of testicular adrenal rest tumors, impaired spermatogenesis, and Leydig cell failure in adolescent and adult males with congenital adrenal hyperplasia.

In male patients with congenital adrenal hyperplasia, testicular tumors, or so-called adrenal rest tumors, have been described, but their presence in well controlled patients is thought to be rare. In this study, the prevalence of testicular tumors in 17 adolescent and adult male patients with congenital adrenal hyperplasia (age, 16-40 yr) was investigated. In 16 of 17 patients, one or more testicular tumors, ranging in maximal length from 0.2-4.0 cm, were found on ultrasonography. In 6 patients, the testicular tumors were palpable. Undertreatment, defined as the presence of a salivary androstenedione level (mean of 6 saliva samples collected over 24 h with intervals of 4 h) above the upper reference morning level, was found in 5 of 17 patients at the time of investigation. The other 12 patients were treated adequately or even over treated at the time of investigation. Nevertheless, 11 of these 12 patients showed testicular tumors on ultrasonography. Neither the presence of undertreatment at the time of investigation nor characteristics of the therapeutic regimen (daily dose of hydrocortisone equivalents per body surface, the use of glucocorticoid medication either two or three times a day, or the time of taking the highest glucocorticoid dose either in the morning or the evening) could predict tumor size (maximal diameter of largest tumor). In patients who were heterozygous or homozygous for the deletion or conversion of the CYP21 gene, tumor size was significantly larger than in patients who did not have this genotype. Impairment of Leydig cell function as manifested by decreased plasma levels of T was found in 6 of 17 patients. Semen analysis in 11 patients revealed azoospermia in 3 patients and poor semen quality in 4 patients. We conclude that, when carefully sought for, testicular adrenal rest tumors are frequently present in adolescent and adult males with congenital adrenal hyperplasia and are often accompanied by impaired spermatogenesis and Leydig cell failure.

In vivo proton MR spectroscopy reveals altered metabolite content in malignant prostate tissue.

BACKGROUND: Recently the potential of magnetic resonance (MR) methods for non-invasive diagnosis and therapy evaluation of prostate cancer has improved substantially. In this study proton MR spectroscopy (1H MRS) was explored for the detection of cancer in the prostate. PATIENTS AND METHODS: Employing an endorectal probe localized 1H MRS and contrast enhanced MR imaging was performed on the prostate of healthy volunteers and of patients with benign prostatic hyperplasia (BPH) and/or prostate cancer (PCa). RESULTS: 1H MR spectra of the human prostate showed major signals for citrate, creatine and choline compounds. For cancer tissue the average citrate/choline signal ratio was significantly lower than for BPH and non-cancerous peripheral and central zone tissue, but individual ratios overlapped with ratios for normal central zone and BPH tissue. Low citrate/choline ratios in tumour tissue correspond with early MR contrast enhancement. CONCLUSIONS: 1H MRS has potential for non-invasive detection and follow-up of tumours in the prostate.

Accuracy of rigid CT-FDG-PET image registration of the liver.

Diagnostic and surgical strategies could benefit from accurate localization of liver malignancies via CT-FDG-PET image registration. However, registration uncertainty occurs due to protocol differences in data-acquisition, the limited spatial resolution of positron emission tomography (PET) and the low uptake of 18F-fluorodeoxyglucose (FDG) in normal liver tissue. To assess this uncertainty, methods were presented to estimate registration precision and systematic bias. A semi-automatic, organ-focused method was investigated to minimize the uncertainty well beyond the typical uncertainty of 5-10 mm obtained by commonly available methods. By restricting registration to the liver region and by isolating the liver on computed tomography (CT) from surrounding structures using a thresholding technique, registration was achieved using the mutual information-based method as implemented in insight toolkit (ITK). CT and FDG-PET images of 10 patients with liver metastases were registered rigidly a number of times. Results of the organ-focused method were compared to results of three commonly available methods (a manual, a landmark-based and a 'standard' mutual information-based method) where no dedicated image processing was performed. The proposed method outperformed the other methods with a precision (mean+/-s.d.) of 2.5+/-1.3 mm and a bias of 1.9 mm with a 95% CI of [1.0, 2.8] mm. Unlike the commonly available methods, our approach allows for robust CT-FDG-PET registration of the liver, with an accuracy better than the spatial resolution of the PET scanner that was used.

Cryosurgery as treatment modality for colorectal liver metastases.

Liver metastases occur in more than 40% of the patients with colorectal cancer. The best prospect of cure is achieved by resection of the metastases. Only 10-15% of the patients with colorectal metastases are candidates for resection. When resection is impossible, other treatment options are limited. Response rates to chemotherapy are around 40%, but survival benefit is generally limited to a few months. Recently, cryosurgery has provided a new therapeutic approach for unresectable colorectal liver metastases. The metastases are localized by ultrasonography and are subsequently frozen with the aid of cryosurgical equipment. The treatment results in necrosis of the tumor and is characterized by low mortality and acceptable morbidity. Experience with cryosurgery is limited, but the results are promising. Various studies report a 1-year survival of more than 70% and a 2-year survival of > 50%. Disease-free survival after 2 years varies between 20-29%. Recurrences in the liver are usually other lesions than those treated with cryosurgery. Cryosurgery in combination with resection or as sole treatment, can result in radical treatment for patients formerly considered unresectable. Resection of liver metastases, however, remains the gold standard in the treatment of liver metastases. The main indication for cryosurgery may be as a complement to hepatic resection in those patients in whom liver resection can not achieve complete tumor clearance.

[A role for cryosurgery in the treatment of non-resectable liver metastases of colorectal neoplasms]. / De plaats van cryochirurgie bij de behandeling van niet-resectabele levermetastasen van colon- en rectumcarcinoom.

Liver metastases occur in over 40% of patients with colorectal carcinomas. The best prospect of cure is achieved by resection of the metastases. However, only 10-15% of the patients with hepatic metastases are estimated to be candidates for resection. When curative resection cannot be performed the options for treatment are limited. Response rates to chemotherapy are around 40% and even then survival benefit is generally limited to a few months. Hepatic cryosurgery recently provided a new therapeutic approach for unresectable liver metastases. For cryosurgery tumour tissue is located by ultrasonography and then cooled by liquid nitrogen to a temperature of -196 degrees C, which results in necrosis of tumour tissue. In a limited number of series encouraging results of cryosurgery have been reported. One year and two year survival rates of respectively 70% and 50% were reported after cryosurgery for hepatic metastases. Disease free survival rate after 2 years varies from 20% to 28%. If recurrence of the disease occurred in the liver it was generally outside the areas treated by cryosurgery. Benefit in survival is only achieved when all tumour tissue is treated adequately. Hepatic cryosurgery is appropriate in those patients with unresectable metastatic disease in whom cryosurgery alone or in combination with resection is able to eradicate all metastatic disease in the liver.

[High-flow priapism: a rare, easily treatable disorder with excellent prognosis]. / 'High-flow'-priapisme: een zeldzame, goed behandelbare aandoening met uitstekende prognose.

Four patients, men aged 33, 37, 37 and 12 years, were examined because of priapism following trauma. In all four high-flow priapism was diagnosed, based on intracavernous blood gas analysis and selective angiography. One of the men aged 37 was subsequently found to be suffering from low-flow priapism caused by chronic myeloid leukaemia (the blood gas analysis had been performed after decompression of the cavernous body). Two other patients were treated by selective internal pudendal artery embolisation. In the fourth, who developed a vascular spasm at angiography, embolisation was not performed: he recovered spontaneously. In contrast to high-flow priapism, low-flow priapism is an urological emergency for diagnosis and treatment to prevent permanent impotence.

Ultrasound-guided radiofrequency ablation of early breast cancer in a resection specimen: lessons for further research.

PURPOSE: To assess the feasibility and effectiveness of radiofrequency ablation (RFA) in breast cancer, using different histopathologic staining methods to evaluate tissue viability. MATERIALS AND METHODS: In twenty patients with unifocal small (≤1, 5 cm) invasive ductal carcinoma, ultrasound-guided RFA was performed immediately after surgery. Cell viability was assessed using cytokeratin 8 (CK 8) and nicotinamide adenine dinucleotide diaphorase (NADHD) in addition to hematoxylin-eosin (HE). RESULTS: At histopathological examination, ex vivo RFA resulted in complete cell death of the target lesion in 17/20 patients. In two cases viable ductal carcinoma in situ (DCIS) was found just outside the completely ablated lesion. CONCLUSION: RFA of small invasive breast cancer seems to be a feasible treatment option. Both NADHD and CK 8 demonstrate a clear and comparable demarcation between viable and non-viable tissue. A high level of accuracy is required in proper positioning of the needle electrode and a "hot retraction" is mandatory.

Use of cytokeratin 8 immunohistochemistry for assessing cell death after radiofrequency ablation of breast cancers.

The effects of minimally invasive therapies such as radiofrequency ablation (RFA) and laser induced thermal therapy on breast carcinoma lesions usually is assessed by NADH diaphorase enzyme histochemistry for cell viability. NADH staining requires frozen material, however, with its associated poor morphology. We aimed to validate cytokeratin 8 (CK 8) immunohistochemistry as an alternative that works on paraffin sections. RFA was performed ex vivo on 20 breast resections after surgery and in vivo in eight patients who underwent general anesthesia followed by immediate resection. After treatment, specimens were lamellated and the tumors were divided into two equal parts. One part was fixed in neutral buffered formaldehyde for routine histopathological evaluation using hematoxylin and eosin (H & E) staining and CK 8 immunostaining. The other section was snap frozen and stored at -80° C for staining with NADH diaphorase. Both NADH diaphorase and CK 8 immunostaining demonstrated a clear and comparable demarcation between viable and nonviable tissues. The morphology of the CK 8 immunostained slides was much better, and fatty tissues could be judged readily by contrast to the NADH stained frozen sections, which had poor morphology and whose fatty parts were difficult to interpret. CK 8 immunohistochemistry seems to be well suited for assessing cell viability in breast tissue and for assessing the effects of RFA for breast cancer treatment. Because it can be applied to paraffin fixed material, it provides much better morphology than NADH staining and also can be applied to fatty tissues that usually are difficult to work up for frozen sections. Therefore, CK 8 immunohistochemistry may be preferred over NADH diaphorase staining for daily pathology practice for assessing the viability of breast carcinoma cells after RFA treatment.