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Volume Doubling Time (volume + doubling_time)

Distribution by Scientific Domains
Medical Sciences100%

Selected Abstracts

Radiotherapy for hepatocellular carcinoma: Systematic review of radiobiology and modeling projections indicate reconsideration of its use

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 4 2010
Alan J Wigg
Abstract Background and Aims:, External beam radiotherapy currently has a limited role in the treatment of hepatocellular carcinoma (HCC). The purpose of this article was to review available radiobiological data on HCC and normal liver and incorporate these data into radiobiological models that may be used to explain and improve treatment. Methods:, Volume doubling times of HCC were described and used to demonstrate growth of HCC with time, assuming both exponential and logistic growth. Radiosensitivity of HCC was described and used to demonstrate the probability of uncomplicated tumor control as tumor size increases. The relationship between tolerance of liver to irradiation and volume irradiated was examined. Results:, The median volume doubling time for untreated HCC was 130 days. HCC have a long period of subclinical growth. Radiosensitivity of HCC lies within the range of other tumors commonly treated with radiotherapy. When treating small volumes of normal liver, relatively high doses may be used with low risk of late radiation damage. There is a high probability of sterilizing subclinical disease and small HCC with tolerable radiation doses. Conclusion:, New radiobiological data, modeling, emerging clinical data and the advantages offered by standard external beam radiotherapy techniques suggest the need for reconsidering the use of radiotherapy and for new trials. [source]

A critical appraisal of prognostic and predictive factors for common lung cancers

HISTOPATHOLOGY, Issue 7 2006
F B J M Thunnissen
The outlook for patients with lung cancer remains poor despite advances in the understanding of the pathology and biology of this disease. To optimize treatment protocols prognostic data are essential. The current era with molecular research on mRNA expression analysis and proteomics will lead to a plethora of new molecular markers, which are likely to be correlated, at least in part, with each other and with disease activity, progression and survival. However, although the number of prognostic factors analysed in published systematic reviews on lung cancer is large, the scope of these factors in individual studies is often narrow. In daily practice prognostic factors other than general TNM staging are not implemented. To assess the efficacy of new prognostic factors for the management of individual patients with non-small cell lung cancer, studies with clinically relevant modelling are required. In this review arguments are provided to use a model combining radiological and histopathological growth rate, histopathological diagnosis and molecular characteristics as markers for metastatic capacity, tumour volume doubling time and expected response to targeted therapy. This may reveal time-related predictive information useful for treatment guidance of the individual patient. [source]

Surveillance programme for hepatocellular carcinoma improves the survival of patients with chronic viral hepatitis

LIVER INTERNATIONAL, Issue 1 2008
Grace Lai-Hung Wong
Abstract Background: The survival benefit of surveillance for hepatocellular carcinoma (HCC) is controversial. Aim: We aimed to examine the survival benefit of HCC surveillance in chronic viral hepatitis. Methods: Survivals of HCC patients related to chronic viral hepatitis from the Hepatology Clinic (surveillance group) were compared with those referred from other hospitals/clinics (no-surveillance group). Lead-time and length-time biases were adjusted based on tumour volume doubling times. Results: Among 579 patients (91% hepatitis B), 472 (82%) patients had HCC and 79 (17%) of these patients were referred from the surveillance programme. HCC was smaller (4.2 vs. 7.7 cm; P<0.001) and fewer in numbers (2.6 vs. 3.8, P=0.03) in the surveillance group vs. the no-surveillance group. Treatment by surgery (20 vs. 10%, P=0.007) and local ablative therapy (46 vs. 19%, P<0.001) were more frequent in the surveillance group than that in the no-surveillance group. The median survival of the surveillance group (88 weeks) was significantly longer than that of the no-surveillance group (26 weeks) (P<0.001). The adjusted cumulative survival at 2 years was significantly longer in the surveillance group if the tumour volume doubling time was <90 days (P=0.0352). Conclusions: HCC surveillance can improve the survival of patients with chronic viral hepatitis B. [source]