REVIEW ONCOLOGY

Transforming growth factor β: friend or foe in disguise?

TGF-β is a major regulator and driver of many biological processes, but its main function is inhibition of cell cycle progression and apoptosis, thus establishing a tumour-protective effect in early stages of malignant transformation. However, mutational alterations can occur at different levels of the TGF-β signaling cascade. These mutations, combined with the significant influence of the tumour microenvironment on this cascade, can cause a functional shift of TGF-β from being a tumour suppressor to becoming a tumour promoter in more advanced cancers. In most tumours this will ultimately contribute to the formation of metastatic laesions. In the clinical setting of breast cancer, TGF-β plays a significant role in the acquisition of endocrine resistance. Thus, therapeutic intervention of TGF-β signaling might deliver significant benefits in the treatment of cancer. (BELG J MED ONCOL 2012;6:188–193)

The spectrum hypothesis and the technical revolution in radiotherapy at the origin of a major paradigm shift

“Predicting is difficult, especially predicting the future….”

The evolution in radiotherapy nowadays allows highly conformal treatment. Even for moving targets, the radiation therapy can be given with high precision, avoiding as much as possible the irradiation of healthy tissue. This allows reduction of the number of fractions and increase of the biological effect of the treatment. The literature shows us that this increase in biological effect opens the perspective of ablative radiotherapy as an alternative to surgery, whether this is for selected primary tumours or for limited metastatic sub-sites. This ablative radiotherapy will change the treatment paradigms in oncology radically. It is cost-effective, non-invasive and, as the treatment is given in a limited number of fractions not requiring a hospital stay, it has no negative impact on the quality of life of the patient. (BELG J MED ONCOL 2012;6:151–156)

Guidelines in oncology

Guidelines are important tools in relation to patient treatment and care in oncology. They are systematically developed statements to assist practitioner- and patient-decisions about appropriate health care for specific clinical circumstances. They are needed because of unexplained and inappropriate variations in clinical practice patterns, different cancer treatment outcomes, further limitations in resources affecting administration of high quality health care, difficulties of integrating rapidly evolving scientific evidence into daily clinical practice, guidance for involved stakeholders and quality control. A guideline development programme should be inclusive, transparent, consultative, evidence-based and adhering to internationally recognised standards of practice such as the AGREE Collaboration. There should be an implementation plan to ensure that guidelines are implemented in daily clinical practice since they have an important influence on cancer outcome. This article reviews the need, development, implementation, adherence and outcome of guidelines. (BELG J MED ONCOL 2012;6:112–117)

Review: management of bone metastases

Bone metastases are common in many cancers. They can cause a wide range of symptoms impairing quality of life and shortening survival. Direct complications of bone involvement include severe pain, pathologic fractures, hypercalcaemia and spinal cord compression. Evaluation is critical to assess location and extent of bone metastases. This includes clinical and neurological examination. Possible imaging studies are: radiographs, skeletal scintigraphy, CT, MRI and 18-FDG-PET. The management of bone metastases is multidisciplinary. Bisphosphonates are commonly the most frequently used osteoclast inhibitors and should always form part of treatment. Radiotherapy is most efficient for pain relief. (BELG J MED ONCOL 2012;6:80–86)

Current perspectives on the use of the Gleason grading system for prostate cancer

For more than four decades the Gleason score is the most widely accepted histopathological grading system for prostate cancer. It is a 5-tier grading system that correlates with tumour differentiation and is solely based on architectural patterns within the tumour. Although robust over time, revision of Gleason grading became unavoidable as diagnosis and treatment of prostate cancer also underwent an enormous evolution over time. In 2005 the International Society of Urological Pathology (ISUP) proposed several modifications to the Gleason system which should keep this grading system timely. This review compares the original system to the modified Gleason system and especially focuses on the prognostic relevance of the modifications. It further deals with the question if the Gleason system will be able to keep its prominent role in the diagnostic and prognostic algorithm for prostate carcinoma, especially in the nearby molecular era. (BELG J MED ONCOL 2012;6:45–51)

The biology and role of epithelial to mesenchymal transition in solid tumours

Epithelial-mesenchymal transitions (EMT) occur as key steps during embryonic morphogenesis and are now implicated in the progression of primary tumours towards metastases, but also towards the accumulation of stem-cell properties. Recent advances have fostered a more detailed understanding of molecular mechanisms and networks governing EMT and leading to more dedifferentiated and malignant states. Owing to the clinical importance of the EMT-induced processes, inhibition of EMT is an attractive therapeutic approach that could have significant effect on disease outcome.

(BELG J MED ONCOL 2012;6:3–12)