Peter Lim

Population-based treatment and outcomes of Stage I uterine serous carcinoma

OBJECTIVE Uterine serous carcinoma (USC) is a rare type of endometrial cancer that often recurs in patients with Stage I disease. Our objective was to evaluate treatment and outcomes in Stage I USC in the context of a population-based study. METHODS This was a population-based retrospective cohort study of all patients with Stage I USC in British Columbia, Canada from 2004 to 2012. The British Columbia Cancer Agency (BCCA) recommends three cycles of paclitaxel and carboplatin chemotherapy followed by pelvic radiotherapy for all women with Stage I USC and any myometrial invasion (Stage IA MI-). If no myometrial invasion (Stage IA MI-), no postoperative treatment is given. Patient and disease characteristics, surgery, adjuvant therapy, recurrence rates and sites, and 5-year disease-free survival rates were evaluated. RESULTS Of the 127 patients with Stage I USC, 41 were Stage IA MI-, 56 Stage IA MI+, and 30 Stage IB. Median follow-up was 25 months (2-98 months). Five year disease-free survival rates were 80.7%, 74.4%, and 48.5% for Stages IA MI-, IA MI+, and IB, respectively, and recurrence rates according to BCCA guidelines were 10%, 2.9% and 30%, respectively. Of the 18 with recurrences, 13 had a distant component (72.2%). There were no pelvic recurrences among those receiving adjuvant radiotherapy. CONCLUSION Our current protocol of observation alone postoperatively for Stage IA MI- and chemoradiotherapy for Stage IA MI+ is associated with a low recurrence rate. In contrast, those with Stage IB USC have a higher recurrence rate despite chemoradiotherapy, and likely require alternate treatment strategies.

Effect of breathing carbogen on the oxygen tension of murine and human tumours measured using an Eppendorf pO2 histograph.

For decades the presence of hypoxic cells within solid tumours has been regarded as an impediment to the efficacy of radiotherapy (Thomlinson and Gray, 1955). Several treatment modalities have been developed with the aim of overcoming the problem posed by hypoxic cells though, so far, they have had minimal clinical impact (Hall, 1994). Most efforts have centred around either supplying more oxygen to tumour tissue, with the aim of increasing the oxygen tension in the hypoxic cells and thus increasing their sensitivity to radiation or administering drugs which selectively increase the sensitivity of hypoxic cells to radiation (Dische, 1991). More recently drugs have been developed which exhibit selective toxicity to cells at lower than normal oxygen tension (Brown, 1993). The aim of treatment with these “bioreductive cytotoxins” is to kill the hypoxic cells whilst conventional radiation / chemotherapy eradicates the more oxygenated tumour cells.

15: Feasibility of Collecting Patient Reported Outcomes for Patients Receiving Curative Intent RT for Gynecological Malignancies

CARO 2016 _________________________________________________________________________________________________________ was sent to all 14 provincial cancer centres in 2013. The survey included 72 questions in four different categories: general/demographic, pre-treatment assessment, EBRT and BT questions. Results: The response rate was 100%. Ten out of 14 centres treated cervical cancer patients and had a dedicated brachytherapy suite. All 10 centres that treated cervix cancer had a peer review process for quality assurance (QA). Nine centres had written treatment planning and delivery protocol and five centres used a specific plan evaluation protocol for organs at risk for EBRT. The standard EBRT technique was 4-field box in eight centres and one centre used IMRT if treating the para-aortic nodes simultaneously; one centre did not respond. The dose/fractionation scheme to the whole pelvis was 45-50 Gy in 1.8-2 Gy per fraction in all but one centre. Nine centres used image verification at some point during EBRT. All ten centres used HDR brachytherapy and one centre also used PDR brachytherapy to treat cervix cancer patients. Brachytherapy was performed under general anesthesia, regional anesthesia and conscious sedation in four, one and five centres, respectively. Only one centre offered interstitial brachytherapy. The majority of centres (eight of 10) used ultrasound image guidance for intrauterine applicator insertion. For treatment planning two centres used CT and MRI, four centres used CT only and four centres used orthogonal x-rays. GEC-ESTRO guidelines were used in three centres for target volume delineation and in five centres for organs at risk (OAR) dose constraints. Nine centres prescribed and reported dose to Point A. Volumetric dose prescription was performed in one centre and four centres reported dose to a target volume. Eight centres reported dose to OARs. The number of BT applicator insertions varied significantly between the centres ranging from one to six. The dose prescription was also variable ranging from 5.5 Gy to 8 Gy per fraction. Conclusions: The main findings from the survey were the variation in the BT dose fractionation and treatment planning used in the regional cancer centres while there was a general uniformity in peer reviewed QA, written institutional treatment protocol, EBRT technique, dose fractionation scheme and use of HDR BT across the province. This study shed light on the need to implement a harmonized evidence-based brachytherapy practice for cervical cancer in order to improve patients’ outcome across Ontario, Canada.