Normal tissue complications

A clinical trial to evaluate misoprostol as a protector of normal tissue during a course of XRT in cancer patients suggests a reduction in acute normal tissue injury (215). A randomized, prospective, double-blind study indicates that topical misoprostol, administered as an oral rinse 15-20 min before irradiation using conventional 2-Gy (200 rad) fractions, five days a week over 6—7 weeks, significantly protects the oral mucosa from radiomucositis, a frequently observed normal tissue complication during XRT for head and neck cancer (215). 

Radiotherapy has a vital role in the curative treatment of many common malignancies, including cancers of the head and neck, prostate, bladder, rectum, lung, cervix, uterus, and breast. There is a radiotherapy dose-response relationship for tumor control at most of these primaiy sites. There is also a steep dose response for normal tissue injury late onset, progressive atrophy, and fibrosis." For the individual patient, the prescribed dose aims to achieve the optimal balance between the risk of cancer recurrence and the risk of treatment-induced complications. Restrictions... 

Under certain conditions, the Gompertzian tumor model provides an accurate barometer for tumor growth in vivo. However, deviations occur over time due to selection and expansion sub-clones that are chemo-resistant. Skipper s Cell Kill Hypothesis is based on the notion that chemotherapy will lead first-order cell kill kinetics. Therefore, each administration of chemotherapy will produce tiie same fraction of tumor cell death. In theory, it is believed that a log-cell drop of 9 to 11 orders of magnitude is required for tumor eradication. Clinically this scenario is complicated by the chemosen-sitivity of normal tissue and tumor, pharmacokinetic hetereogeneity of patients, and tumor heterogeneity. 

The complications of embolotherapy are well described, but vary in their manifestations depending on the affected end-organ [85, 86]. By nature, success depends on complete abolishment of vascular supply, be it normal or abnormal vasculature. This can often be accomplished but not without a risk of compromise to adjacent normal tissue. Moreover, aggressive pursuit of difficult vascular territories poses a risk for non-target embolization. 

Osteogenesis imperfecta (01) is an inherited disorder of connective tissue resulting from abnormal quantity and/or quality of type I collagen, the major protein of bone. The phenotypic presentation is enormously varied, ranging from perinatal death to normal lifespan complicated by only a few fractures. Because fractures are a feature of the condition it must be given serious consideration in any child with unexplained fractures. There are four major types in the Sillence classification (Sillence et al. 1979), but it should be noted that there are no strict boundaries. Type IV is an uncommon type of 01 (only 5% of the patients in the Sillence study) with mild to severe bone disease. Patients with this type... 

The most common areas for psoriasis in human are shown on the scalp[3, 4], Initially, a series of classical treatment is used to treat this disease but that attempt has been failed. Today, phototherapy and PDT have become a regular modality and effective way for psoriasis and actinic keratoses treatment[4]. In spite of the various by topical treatments available for the treatment of superficial skin disease in scalp skin, many patients not succeed to respond adequately or may develop side effects. The goal of PDT treatment of psoriasis and actinic keratoses is to cure or locally control the disease while minimizing complications in normal tissues and reducing pain regarding therapy by investigation the influence of optical properties of skin and hair. 

Cirrhosis is the progressive replacement of normal hepatic cells by fibrous scar tissue. This scarring is accompanied by the loss of viable hepatocytes, which are the functional cells of the liver. Progressive cirrhosis is irreversible and leads to portal hypertension that is in turn responsible for many of the complications of advanced liver disease. These consequences include (but are not limited to) spontaneous bacterial peritonitis (SBP), hepatic encephalopathy, and variceal bleeding.1... 

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