The Role of Survivin for Radiation Therapy

BACKGROUND: Survivin, the smallest member of the inhibitor of apoptosis protein (IAP) family, is a bifunctional protein that has been implicated in both control of cell division and inhibition of apoptosis. MATERIAL AND METHODS: This review specially focuses on clinical and experimental data on the relevance of survivin in radiooncology and its role as a therapeutic target to radiosensitize tumor cells. RESULTS: As compared to normal tissue, survivin is overexpressed in tumors and appears to be closely related to tumor malignancy and treatment response. In addition, survivin is involved in the resistance of tumor cells to both chemotherapy and ionising irradiation. Due to these properties, survivin has been proposed as an attractive target for anticancer therapies. Several preclinical studies have demonstrated that suppression of survivin, by the use of antisense oligonucleotides, small interfering RNAs, ribozymes and the application of dominant negative mutants, increases apoptosis, diminishes tumor cell survival and reduces tumor growth potential. CONCLUSION: Survivin displays a relevant prognostic and predictive factor as well as a promising molecular target to improve the effectiveness of radiotherapy.     

Merkel Cell Carcinoma: The Role of Radiation Therapy in General Management

Background: Merkel cell carcinoma (MCC) is a rare malignant, locally aggressive tumor of the skin. Because few data exist about the clinical course of irradiated patients, we reviewed the 17 patients treated at our institution since 1982. Patients and Methods: The median age at diagnosis was 71 years (range 47 to 88 years). Twelve patients presented with lymph node involvement (Stage II), 5 patients with negative lymph nodes (Stage I). Five patients were irradiated immediately after initial surgical excision of the primary tumor. Eleven patients underwent a surgical treatment of recurrence prior to the first irradiation. Only 1 patient received primary radiotherapy. A median dose of 52.8 Gy (range 40 to 60 Gy) in the region of the primary tumor and a median dose of 49.5 Gy (range 30 to 54 Gy) in the regional lymph nodes were delivered. Results: The median overall survival after first diagnosis was 45 months. Three-year overall survival was 57%, 5-year cause-specific survival was 73% (Kaplan Meier). Local control could be achieved in the 5 patients irradiated immediately after surgical treatment of the primary tumor. In contrast, an in-field recurrence occurred in 5 of 12 patients irradiated after surgical excision of relapsed disease. Five patients developed distant metastases. None of these patients was irradiated immediately after surgical excision of the primary tumor. Conclusions: With respect to our experience, a local control can be achieved with an immediate postoperative radiotherapy of the primary tumor site and the adjacent lymph nodes. Hintergrund: Merkel-Zell-Karzinome sind seltene maligne, aggressiv wachsende Tumoren der Haut. Da wenige Daten bestrahlter Patienten verfügbar sind, soll der Stellenwert der Strahlentherapie bei der Behandlung des Merkel-Zell-Karzinoms anhand von 17 seit 1982 in unserer Klinik behandelten Patienten diskutiert werden. Patienten und Methoden: Das mediane Alter der Patienten war 71 Jahre (47 bis 88 Jahre) bei Diagnosestellung (Tabelle 1). Zwölf Patienten präsentierten sich mit Lymphknotenbefall (Stadium II), fünf Patienten mit negativen Lymphknoten (Stadium I). Fünf Patienten wurden sofort nach Operation des Primärtumors bestrahlt. Elf Patienten wurden vor Beginn der ersten Bestrahlung an einem Rezidiv operiert. Nur ein Patient wurde primär bestrahlt. Eine mediane Dosis von 52,8 Gy (40 bis 60 Gy) wurde im Bereich der Primärtumorregion appliziert. Die regionalen Lymphabflußwege wurden mit einer medianen Dosis von 49,5 Gy (30 bis 54 Gy) bestrahlt. Ergebnisse: Das mediane Überleben nach Erstdiagnose lag bei 45 Monaten. Die Drei-Jahres-Überlebenswahrscheinlichkeit war 57% (Abbildung 1). Die krankheitsspezifische Fünf-Jahres-Überlebenswahrscheinlichkeit lag bei 73% (Kaplan-Meier). Eine lokale Kontrolle wurde bei den fünf Patienten erreicht, die sofort nach Operation des Primärtumors bestrahlt wurden. Bei fünf der elf Patienten, die erst nach Operation eines Rezidivs bestrahlt wurden, trat ein Rezidiv im Bestrahlungsfeld auf. Fünf Patienten erlitten nach Therapieabschluß eine Fernmetastasierung. Keiner dieser Patienten wurde sofort nach Operation des Primärtumors bestrahlt. Schlußfolgerung: Durch eine sofortige Bestrahlung der Tumorregion und der regionalen Lymphabflußwege nach Operation des Primärtumors kann nach unserer Erfahrung eine lokale Kontrolle der Merkel-Zell-Karzinome erreicht werden.     

Merkel Cell Carcinoma: The Role of Radiation Therapy in General Management

BACKGROUND: Merkel cell carcinoma (MCC) is a rare malignant, locally aggressive tumor of the skin. Because few data exist about the clinical course of irradiated patients, we reviewed the 17 patients treated at our institution since 1982. PATIENTS AND METHODS: The median age at diagnosis was 71 years (range 47 to 88 years). Twelve patients presented with lymph node involvement (Stage II), 5 patients with negative lymph nodes (Stage I). Five patients were irradiated immediately after initial surgical excision of the primary tumor. Eleven patients underwent a surgical treatment of recurrence prior to the first irradiation. Only 1 patient received primary radiotherapy. A median dose of 52.8 Gy (range 40 to 60 Gy) in the region of the primary tumor and a median dose of 49.5 Gy (range 30 to 54 Gy) in the regional lymph nodes were delivered. RESULTS: The median overall survival after first diagnosis was 45 months. Three-year overall survival was 57%, 5-year cause-specific survival was 73% (Kaplan Meier). Local control could be achieved in the 5 patients irradiated immediately after surgical treatment of the primary tumor. In contrast, an in-field recurrence occurred in 5 of 12 patients irradiated after surgical excision of relapsed disease. Five patients developed distant metastases. None of these patients was irradiated immediately after surgical excision of the primary tumor. CONCLUSIONS: With respect to our experience, a local control can be achieved with an immediate postoperative radiotherapy of the primary tumor site and the adjacent lymph nodes.     

A code of ethics for the medical dosimetrist - The American Association of Medical Dosimetrists Experience

The Committee on Protocol and Ethics of the American Assoclation of Medical Dosimetrists (AAMD) has developed a Code of Ethics for a radiation oncology society of medical dosimetrists. The purpose of the code of ethics is fourfold: (1) Establish an ideal of professional conduct specific to the medical dosimetry profession; (2) Develop a statement of the moral values and commitment of the AAMD; (3) Recognize professional relationships and obligations; and (4) Define goals to which the medical dosimetrist should aspire. The Code of Ethics was adopted as AAMD policy in October 1995.     

The Role of Radiation Therapy in the Management of Desmoid Tumors

PURPOSE: To investigate the role of radiation therapy (RT) in the management of desmoid tumors. PATIENTS AND METHODS: Retrospective analysis was performed on 28 patients with desmoid tumors treated with radiation therapy between March 1989 and March 1999. Tumor site was intraabdominal in three, abdominal wall in three and extraabdominal in 22 patients. Median tumor dose was 48 Gy (range 36-60 Gy). Radiation therapy was delivered postoperatively in 26 of 28 patients, two patients received radiation therapy for unresectable recurrent tumors. RESULTS: Median follow-up was 46 months (range 13-108 months). Actuarial 5-year control rate was 73%. We observed six recurrences, located within the radiation field in one patient, out of field in two and at the field margin in three patients. All patients with intraabdominal tumors have been controlled without severe side effects. CONCLUSIONS: Radiation therapy is an effective treatment after incomplete resection of desmoid tumors. We did not observe a benefit for tumor doses exceeding 50 Gy. In some patients with circumscribed intraabdominal desmoid tumors, radiation therapy might be a treatment option with low toxicity, if 3-D treatment planning is utilized.     

Just Culture: Practical Implementation for Radiologist Peer Review

Peer review is a cornerstone of quality improvement programs and serves to support the peer learning process. Peer review in radiology incorporates the review of diagnostic imaging interpretation, interventional procedures, communication, and the evaluation of untoward patient events. A just culture is an environment in which errors and near-miss events are evaluated in a deliberately nonpunitive framework, avoiding a culture of blame and responsibility and focusing instead on error prevention and fostering a culture of continuous quality improvement. Adoption of a just culture requires careful attention to detail and relies on continuous coaching of individuals and teams to ensure future systems improvements and a culture of safety. The authors describe the practical implementation of a just culture framework for peer review in an academic radiology department and highlight its application to interpretive, noninterpretive, and procedural domains through case examples.