CT texture analysis in colorectal liver metastases and the surrounding liver parenchyma and its potential as an imaging biomarker of disease aggressiveness, response and survival.

OBJECTIVES: To study the ratio between the CT texture of colorectal liver metastases (CRLM) and the surrounding liver parenchyma and assess the potential of various texture measures and ratios as predictive/prognostic imaging markers. MATERIALS: Seventy patients with colorectal cancer and synchronous CRLM were included. All visible metastases, as well as the whole-volume of the surrounding liver, were separately delineated on the portal venous phase primary staging CT. Texture features entropy (E) and uniformity (U) were extracted and ratios between the texture features (T) of the metastases and background liver (Tmetastases/Tliver) calculated. Texture features were compared with clinical outcome parameters: [1] extent of disease (i.e. number of metastases), [2] response to chemotherapy (in 56/70 patients who underwent chemotherapy and CT for response evaluation), and [3] overall survival. RESULTS: The Emetastases/Eliver ratio was lower in patients with limited disease (P = 0.02) and associated with overall survival, albeit not statistically significant when tested in multivariable analyses (HR 1.90; P = 0.07); Umetastases/Uliver was higher in patients with limited disease (P = 0.02). Emetastases showed a trend towards a higher value in patients that responded well to chemotherapy (P = 0.08). CONCLUSION: The ratio between the texture of liver metastases and the surrounding liver appears to reflect relevant changes in tissue microarchitecture and may be of value to assess the extent of disease and help predict overall survival.

Whole-volume vs. segmental CT texture analysis of the liver to assess metachronous colorectal liver metastases.

PURPOSE: It is unclear whether changes in liver texture in patients with colorectal cancer are caused by diffuse (e.g., perfusional) changes throughout the liver or rather based on focal changes (e.g., presence of occult metastases). The aim of this study is to compare a whole-liver approach to a segmental (Couinaud) approach for measuring the CT texture at the time of primary staging in patients who later develop metachronous metastases and evaluate whether assessing CT texture on a segmental level is of added benefit. METHODS: 46 Patients were included: 27 patients without metastases (follow-up >2 years) and 19 patients who developed metachronous metastases within 24 months after diagnosis. Volumes of interest covering the whole liver were drawn on primary staging portal-phase CT. In addition, each liver segment was delineated separately. Mean gray-level intensity, entropy (E), and uniformity (U) were derived with different filters (σ0.5-2.5). Patients/segments without metastases and patients/segments that later developed metachronous metastases were compared using independent samples t tests. RESULTS: Absolute differences in entropy and uniformity between the group without metastases and the group with metachronous metastases group were consistently smaller for the segmental approach compared to the whole-liver approach. No statistically significant differences were found in the texture measurements between both groups. CONCLUSIONS: In this small patient cohort, we could not demonstrate a clear predictive value to identify patients at risk of developing metachronous metastases within 2 years. Segmental CT texture analysis of the liver probably has no additional benefit over whole-liver texture analysis.

Further evidence for an association of HLA-DR7 with basal cell carcinoma on the tropical island of Saba.

OBJECTIVE: To establish the association of HLA alleles (ie, HLA-DR1, HLA-DR4, and HLA-DR7) with individuals with skin cancer on the tropical island of Saba. This island was chosen because most of the white population has fair skin and excessive exposure to sunlight, which results in a high prevalence of skin cancer. DESIGN: HLA typing was performed in 124 white individuals with histologically proven basal cell and/or squamous cell carcinoma and in control subjects. Skin type, the presence of freckling, and the number of actinic keratoses were determined. SETTING: Population-based study. SUBJECTS: Inhabitants of Saba with and without skin cancer. MAIN OUTCOME MEASURE: Presence of HLA-DR1, HLA-DR4, and HLA-DR7 alleles. RESULTS: Associations of HLA alleles with basal cell and squamous cell carcinoma have been reported. The presence of the HLA-DR7 allele was positively associated with the development of basal cell carcinoma (odds ratio, 3.8; 95% confidence interval, 1.1-13.4). Adjustment for skin type, which is a potentially confounding factor for the association between HLA alleles and skin cancer, did not substantially alter this association. No other associations between HLA alleles and skin cancer were found, possibly because of the small size of the study population. CONCLUSION: This study presented further evidence for an association between HLA-DR7 and basal cell carcinoma. Arch Dermatol. 2000;136:1019-1022

Adjuvant high-dose intravenous gammaglobulin in the treatment of pemphigus and bullous pemphigoid: experience in six patients.

At present, initial high-dose prednisone is the treatment of choice for patients with pemphigus and bullous pemphigoid. To reduce the risks associated with long-term corticosteroid treatment, other immunosuppressants are often given as steroid-sparing agents. Occasionally, the dose of steroids cannot be reduced. In this study, we report six patients with pemphigus vulgaris, pemphigus foliaceus and bullous pemphigoid, in whom the daily corticosteroid dose could only be tapered to acceptable, effective, maintenance levels following treatment with high-dose intravenous gammaglobulin.

Effect of ketanserin on macrocirculatory and microcirculatory blood flow in patients with intermittent claudication. A prospective randomized study.

The effect of ketanserin on macrocirculatory and microcirculatory blood flow was investigated in a placebo-controlled, double-blind trial in 11 patients suffering from intermittent claudication using Doppler velocimetry and intravital skin capillary microscopy, respectively. After 1 year of treatment no significant change was observed either in the ketanserin or the placebo group. It appears that ketanserin has no significant effect on macrocirculatory blood flow and microcirculatory nutritional skin blood flow in patients with intermittent claudication.

Microcirculatory haemodynamics before and after vascular surgery in severe limb ischaemia--the relation to post-operative oedema formation.

To determine whether postoperative oedema could be predicted preoperatively by microcirculatory parameters, we studied nutritive capillary blood flow in 21 patients before and after limb salvage procedures. All patients had severe lower limb ischaemia and underwent femoro-popliteal or femoro-crural bypass surgery. The systolic ankle-branchial arm index and systolic toe pressure were used as macrocirculatory parameters. Intravital capillary microscopy was used to measure red blood cell (RBC) and peak RBC velocity and time to peak RBC velocity after release of a 1 min arterial occlusion in the nailfold of the toe. Transcutaneous pO2 was measured on the dorsum of the foot at rest, during oxygen inhalation and following a release of a 5 min occlusion. After surgery the mean systolic ankle-brachial index and systolic toe pressure and all transcutaneous pO2 parameters improved significantly (P less than 0.001). Mean peak RBC velocity increased from 0.156 mm/s to 0.310 mm/s (P less than 0.05), indicating that the reactive hyperaemic response in the capillary bed had improved. Eleven patients developed postoperative oedema. There were no differences in postoperative macro and microcirculatory parameters between the patients with oedema (n = 11) and those without oedema (n = 10). However, preoperatively RBC velocity and peak RBC velocity were significantly lower (P less than 0.05) and time to peak RBC velocity was significantly longer (P less than 0.01) in patients who developed oedema. These findings show that in patients with severe limb ischaemia vascular surgery improves both macro- and microcirculatory blood flow, but that these patients develop oedema after vascular surgery when microcirculatory blood flow is compromised preoperatively.

Foot salvage and improvement of microvascular blood flow as a result of epidural spinal cord electrical stimulation.

Epidural spinal cord electrical stimulation has been suggested as an alternative treatment in patients with limb-threatening ischemia in whom vascular reconstructive surgery is not possible anymore. We studied the effects of epidural spinal cord electrical stimulation on microcirculatory blood flow in 20 patients with ischemic rest pain and ulcers. Angiography showed occluded crural arteries technically unsuitable for reconstructive surgery. Intravital capillary microscopy was used to assess capillary density and diameter and red blood cell velocity before and after a 1-minute period of arterial occlusion. After epidural spinal cord electrical stimulation 18 patients claimed immediate pain relief, which was confirmed by intravital capillary microscopy. Capillary density increased from 10 to 19/mm2 (p less than 0.001), red blood cell velocity increased from 0.088 to 0.496 mm/sec (p less than 0.001), and peak red blood cell velocity after arterial occlusion increased from 0.092 to 0.548 mm/sec (p less than 0.001). Two patients had no immediate pain relief; they did not show improvement of microcirculatory perfusion, and amputation was necessary. During the follow-up period (3 months to 3 years, mean 27 months), six other patients had recurrent ischemic pain, and amputation was necessary. In 12 patients pain relief continued, and ischemic ulcers healed; capillary microscopy confirmed improved microcirculatory blood flow. Microcirculatory parameters were significantly higher in respondents than in nonrespondents (p less than 0.001). Life-table analysis revealed a cumulative foot salvage of 80% and 56% after 1 and 2 years, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)