Spectrum and surgical outcomes of gastrointestinal stromal tumours.

BACKGROUND: Surgery and imatinib are the mainstays of the management of gastrointestinal stromal tumours (GIST). This study aimed to analyse the outcomes in the management of GIST utilising surgery and imatinib. METHODS: Progression-free survival (PFS) and overall survival (OS) were analysed in relation to imatinib therapy, location of tumour, resection margins, type and extent of surgery. Imatinib was administered in the neoadjuvant (maximum 12 months) and adjuvant setting (minimum 36 months) and until disease progression or drug intolerance. Disease response was assessed with the Choi criteria. Survival analysis included calculation of PFS, OS and Kaplan-Meier curves. RESULTS: Sixty-two patients were reviewed and 56 had surgical resection. The median age (range) was 58.5 (8-95) years. The median PFS and OS (IQR) was 24.0 (0-52.0) and 41.0 (15.0-74.0) months, respectively. Thirty-nine (70%) patients were treated with imatinib, with 21 of these in a neoadjuvant setting. In the patients undergoing surgery, surgical margins were R0, R1 and R2 in 41 (75%), eight (15%) and six (11%) respectively. There was an insignificant difference in the overall survival in these three groups. For those having liver metastasectomy and multivisceral resection, the PFS and OS were 32.5 (17.5-60.3) and 28.5 (5.75-49.8) (p = 0.008), and 96.0 (58.5-116) and 80 (50.5-92.3) months (p = 0.033), respectively. CONCLUSION: Whilst the numbers were small, certain trends were observed. Surgery in combination with imatinib offers survival benefit in patients undergoing R0, R1, R2, liver metastases and multivisceral resections.

South African guidelines for receptor radioligand therapy (RLT) with Lu-177-PSMA in prostate cancer.

BACKGROUND: Prostate cancer is an important cause of morbidity and mortality in South Africa, as it is in the rest of the world. In African men, however, prostate cancer tends to follow a more aggressive course when compared to their European counterparts. This is attributed to a plethora of diverse factors of which an underlying genetic component has been shown to be an important aspect. Such differences highlight the need for individualised therapy and for local guidelines. The aim of this guideline is to aid nuclear physicians and other clinicians who manage patients with prostate cancer in the correct identification and treatment of patients who are likely to benefit from receptor radioligand therapy. RECOMMENDATIONS: There are a multitude of treatment modalities available for the treatment of prostate cancer and these therapies may be required at various time points during the course of the disease in any individual patient. A multidisciplinary approach is crucial in deciding which therapy, or combination of therapies, would be most advantageous at particular time points. The multidisciplinary team should include a urologist, oncologist and nuclear medicine physician as a minimum, and should ideally also involve a palliative/pain specialist, a dietician and a psychologist. CONCLUSION: Treatment with 177Lu-PSMA has emerged as a promising systemic modality, which involves the delivery of targeted radiation therapy in the form of ß-particles to sites of tumour tissue. Therapy is provided on an outpatient basis, is well tolerated with relatively few side effects and has a positive effect on overall survival and quality of life. At present, it is used mostly in the setting of advanced, castrate-resistant cancer. Patients are selected (amongst other criteria) based on the prior PSMA-based SPECT/PET/CT imaging (99mTc-,68Ga- or 18F-PSMA), which should demonstrate sufficient receptor expression in order to consider PSMA-based targeted radionuclide therapy. Such imaging of an intended target prior to its therapeutic targeting is known as a theranostic approach.

Blood-brain barrier integrity in a zolpidem-responder patient.

A 27-year-old neurologically disabled but fully conscious male zolpidem-responder patient was investigated for blood brain barrier (BBB) dysfunction 5 years after a traumatic brain injury. A baseline single-photon emission computed tomography (SPECT) technetium-99m-labelled hexamethylpropylene amine oxime (99mTcHMPAO) brain scan was performed and the patient was administered 10 mg zolpidem daily. The patient was rescanned 2 weeks later when 99mTcHMPAO was injected 1 hour after zolpidem application. SPECT technetium-99m-labelled diethylene-triamine-pentacetic acid (99mTcDTPA) BBB scans were also performed before and after zolpidem treatment. There was decreased uptake of 99mTcHMPAO in the left frontoparietal brain region, left temporal region and left thalamus on baseline scanning; this improved within 1 hour after zolpidem treatment at the follow-up scan. The 99mTcDTPA scan remained within normal limits before and after zolpidem treatment. The patient's neurological disabilities, especially coordination, speech and gait, improved markedly. The Barthel Index remained normal, but the Tinetti falls efficacy scale improved from 21/100 to 15/100. The results implied that the underlying cause for the patient's long-term neurological disability and brain suppression was not due to a long-term dysfunctional BBB.