Re-irradiation in Gynaecological Malignancies: A Review.

Re-irradiation in gynaecological malignancies has become an increasingly frequent consideration. This can be delivered in multiple settings, with the most common being a patient with a history of cervical cancer developing a new vaginal cancer or endometrial cancer with local recurrence after hysterectomy and adjuvant pelvic radiation. A systematic review of the literature has unearthed a handful of reports, most delivering brachytherapy, with a small number on both external beam radiotherapy and stereotactic ablative radiotherapy. A detailed review of these papers suggests that it is not possible to draw any firm conclusions or put forward guidelines for this challenging area of gynaecological oncology. Here the author has provided a brief account of each paper, followed by a discussion of the literature, aiming to outline some very broad principles for management. It is recommended that such patients be referred to centres that treat high volumes of gynaecological malignancies, as the experience of the treating oncologist may be the most important factor in the management of these patients.

The influence of MRI scan position on image registration accuracy, target delineation and calculated dose in prostatic radiotherapy.

OBJECTIVE: To investigate the necessity of performing MRI in the radiotherapy position when using MRI for prostatic radiotherapy. METHODS: 20 prostate patients received a CT, diagnostic MRI and an MRI scan in the radiotherapy position. The quality of registration between CT and MRI was compared between the two MRI set-ups. The prostate and seminal vesicles were contoured using all scans and intensity modulated radiotherapy (IMRT) plans were generated. Changes in the target volume and IMRT plans were investigated. Two-tailed paired Student's t-tests determined the statistical significance. RESULTS: There was a decrease in the mean distance from the centre of the bony anatomy between CT and MRI (from 3.9 to 1.9 mm, p-value<0.0001) when the MRI scan was acquired in the radiotherapy position. Assuming that registering CT with an MRI scan in the radiotherapy position is the gold standard for delineating the prostate and seminal vesicles, using a planning target volume delineated on the CT with a diagnostic MRI scan viewed separately, resulted in a mean conformation number of 0.80 instead of the expected 0.98 (p<0.0001). CONCLUSION: By registering CT with an MRI scan in the radiotherapy position, there is a statistically significant improvement in the registration and IMRT quality. ADVANCES IN KNOWLEDGE: To achieve an acceptable registration and IMRT quality in prostatic radiotherapy, neither CT with a separate diagnostic MRI nor CT registered to a diagnostic MRI will suffice. Instead, a CT registered with an MRI in the radiotherapy position should be used.

The role of blood tumor marker measurement (using a biochemical index score and c-erbB2) in directing chemotherapy in metastatic breast cancer.

The role of blood tumor markers in monitoring response in advanced breast cancer is established in endocrine therapy and standard chemotherapy. This study examines marker levels in patients receiving new chemotherapy regimens. Thirty patients were recruited into two multicenter trials in which docetaxel-based regimens were used in 15 patients. The other 15 received doxorubicin-based regimens. Biochemical response calculated from a score using CA15.3, CEA and ESR was compared with UICC response. Marker changes at 2, 4 and 5 months correlated with UICC response at 3, 4(1/2) and 6 months, respectively (p < 0.03). Eleven patients achieved both clinical/radiological and biochemical response at the end of treatment; markers had not yet returned to below cutoffs in seven, suggesting a possible advantage to continue chemotherapy. No patient showed a biochemical response whilst judged clinically/radiologically progressive. Nineteen patients had progressed either clinically/radiologically or biochemically at six months; of these, eight showed progression assessed earlier by markers so that a median of four cycles of chemotherapy could have been saved. Measurements of serum c-erbB2 showed a correlation with tissue c-erbB2 staining in the primary tumor (p < 0.003). Among the patients with positive tissue staining, sequential changes in serum c-erbB2 completely paralleled initial response.