A74 SURVEILLANCE IMAGING FOLLOWING COMPLETELY RESECTED GASTROENTEROPANCREATIC NEUROENDOCRINE TUMORS: A SINGLE CENTER AUDIT OF LOCAL PRACTICE PATTERNS

Background

Neuroendocrine tumours (NET) are a heterogenous group of neoplasms that secrete peptides and neuroamines. For patients with potentially malignant gastroenteropancreatic (GEP) NET, surgical resection represents the only curative option. GEP NETs are characterized by long periods of disease-free survival and time-to-recurrence following surgical resection. Clinical guidelines recommend surveillance with cross sectional imaging, either CT or MRI, for at least 10 years.

Aims

The purpose of this study was to characterize local practice patterns of imaging surveillance (modality, frequency, and duration of follow-up) and how this compares to guideline recommendations.

Methods

We retrospectively reviewed clinical and imaging records from patients diagnosed with well-differentiated GEP NET at our center from January 2005 to July 2020 inclusive. Eligible cases were identified by a data analyst from the Alberta Cancer Board with each case being manually screened for eligibility. Exclusion criteria included patients with metastatic disease at presentation, G1 appendiceal NET < 1 cm, R0 G1 T1 rectal NET, and insulinoma. Location of primary NET, modality of surveillance imaging, date of test and duration of follow-up collected. The mean number of surveillance scans per person and per person-year follow-up based on the location of the primary NET were calculated.

Results

A total of 387 cases were initially retrieved with 62 eligible cases identified. The mean length of follow-up was 71 months (range 8 to 147). The mean number of surveillance scans was 7 (range 2 to 14) and the mean number of surveillance scans per person year was 1.1. Frequency of surveillance scans per year of follow-up did not differ based on the location of the primary tumor (p=0.966). Imaging modalities included cross sectional imaging (MRI and contrast enhanced CT) and nuclear medicine imaging (octreotide, MIBG, F-18 FDG-PET, and Gallium-68 DOTATATE PET CT). Most commonly, cross-sectional imaging was performed with CT or MRI representing 38% (n=166) and 39% (n=170) of all surveillance respectively. Nuclear medicine imaging was used in 15% (n=61) of surveillance scans and 3% used combined cross-sectional and nuclear medicine. Amongst cases with resection date >10 years (n=8) mean length of follow-up was 119 months (9.9 years).

Conclusions

Frequency and modality of imaging at our center is generally in accordance with current clinical guidelines, though the role of nuclear medicine imaging in this setting has not been established. CT and MRI were utilized equally during surveillance. The burden of these modalities in terms of radiation exposure and cost warrants further evaluation.

Funding Agencies

None

Report from the 13th annual Western canadian gastrointestinal cancer consensus conference; calgary, alberta; september 8-10, 2011

The 13th annual Western Canadian Gastrointestinal Cancer Consensus Conference was held in Calgary, Alberta, September 8-10, 2011. Health care professionals involved in the care of patients with gastrointestinal cancers participated in presentation and discussion sessions for the purposes of developing the recommendations presented here. This consensus statement addresses current issues in the management neuroendocrine tumours and locally advanced pancreatic cancer.

Hypertension management in patients with renal cell cancer treated with anti-angiogenic agents

Inhibitors of the vascular endothelial growth factor (vegf-is) signalling pathway have fundamentally changed the treatment of metastatic renal cell carcinoma (mrcc). Hypertension is one of the most common side effects of vegf-is and has been reported with almost every vegf-i used for treatment to date. The exact mechanism of vegf-i-induced hypertension appears complex and multifactorial, and it remains to be fully explained. No randomized clinical trials are available to guide the management of hypertension during vegf-i treatment in mrcc patients. The guiding principles suggested here summarize the consensus of opinions on the diagnosis and management of vegf-i-induced hypertension during treatment of mrcc obtained from an expert working group composed of 4 Canadian medical oncologists and 5 Canadian hypertension specialists. The Canadian Hypertension Education Program guidelines, available literature, and expert opinion were used to develop the guiding principles.

Multicenter phase II study of combined neoadjuvant docetaxel and androgen ablation (ADT) prior to radical prostatectomy (RP) for patients (pts) with high risk localized prostate cancer (LCaP): Pathologic outcomes and 3-year follow-up analyses

5002

Background: Pts with high risk LCaP (cT3, Gleason score > 7 &/or PSA > 20) have an increased risk of relapse with a biochemical failure rate of >50% at 3 years after RP. Docetaxel is active in hormone refractory prostate cancer & potentially beneficial if combined with ADT for treatment naïve disease. The objectives of this trial were to assess the pathologic outcomes & feasibility of docetaxel + ADT in men with LCaP prior to RP. Methods: A phase II multi-center study of newly diagnosed previously untreated pts with clinically LCaP with high-risk features. All pts received ADT (buserelin acetate 6.3 mg q8 weeks x 3 and anti-androgen for 4 weeks) plus docetaxel (35 mg/m2 weekly for 6 out of 8 weeks for 3 cycles) prior to RP. Results: 72 men with a median age of 59 years (range 46–78) were enrolled at 6 sites. Baseline characteristics included: clinical stage T1C, T2 & T3 in 14%, 47% & 39%; and Gleason score <7, 7 & >7 in 10%, 30% & 60% of pts; respectively. Median baseline PSA was 10.8 μg/L (range 1.6–65.6) with PSA < 10 in 47%, 10–20 in 24% & >20 in 29% of pts. Eight pts did not complete protocol therapy because of toxicity (n=4), withdrawal of consent (n=1), or other reasons (n=3). 1 pt had myocardial infarction day 1 post-operatively & 1 pt had DVT 1.5 months after RP. No other major post-operative complications were reported. Of the 64 pts completing protocol therapy, 2 had a complete pathologic response and pathologic stage was T2 in 34 (53%) and T3 in 28 (44%) pts. Four pts had N1 disease & positive surgical margins were identified in 17 (27%). On multivariate Cox regression analysis only baseline Gleason score (=7 vs. >7) was associated with PSA recurrence-free survival (hazard ratio 4.58, 95% CI 1.32–15.93). At a median follow-up of 42.7 months (range 25.6–65.6), 19 (30%) pts have relapsed. Three pts have died at 32.0, 40.0 & 40.3 months, with all deaths attributed to prostate cancer. Conclusions: Combined ADT and docetaxel prior to RP was feasible and resulted in encouraging pathologic outcomes and PSA- recurrence free survival. These data further support the rationale for randomized trials determining the efficacy of chemo-hormonal therapy in pts with clinically LCaP.

[Table: see text]

Randomized phase II trial of irofulven (IROF)/prednisone (P), IROF/capecitabine (C)/P or mitoxantrone (M)/P in docetaxel-pretreated hormone refractory prostate cancer (HRPC) patients (pts)

14513

Background: IROF, a semisynthetic derivative of the natural product illudin S, is a novel DNA binding agent. IROF alone or in combination has shown activity in phase I-II trials in HRPC, notably with IROF/C (Cvitkovic et al, ASCO 2004). Methods: Pts with histologically-proven metastatic HRPC who progressed (RECIST or PSA) during prior docetaxel or within 3 months of discontinuing treatment, with adequate hematologic and organ functions and KPS ≥70% were stratified by pain and randomized to one of three treatments: Arm A: IROF (0.45 mg/kg, day 1 and 8 q3weeks [w]) and P (10 mg po daily); Arm B: IROF (0.4 mg/kg day 1 and 15), C(2000 mg/m2 day 1–15 q4w) and P; or Arm C: M (12 mg/m2 q3w) and P. Primary endpoint was TTP (RECIST, PSA or clinical progression); secondary endpoints included PSA response (≥50% decrease for ≥4 w), pain response, and toxicity; 135 pts are planned in a 2:2:1 ratio. The study was powered to detect a difference in TTP of 1.5 vs 3 months. Results: As of Dec 2005, 78 pts were randomized and treated with ≥ 5 months follow-up (A/B/C: 31/31/16). Median age (A/B/C) 69/70/61, KPS ≥80% 24/28/9, median baseline PSA ng/mL 90/147/235, disease related pain at baseline 61%/58%/63%; other characteristics, including metastatic site distribution, were similar between arms. Safety: 65 pts were evaluated for safety. Median cycles/Pt (A, B, C) 3/2/2; grade 3/4 toxicities (% pts A, B, C): asthenia (4%, 16%, 0%), vomiting (0%, 12%, 0%) and diarrhea (4%, 8%, 0%). The most common grade 3/4 laboratory abnormalities were neutropenia (10%, 6%, 31%) and thrombocytopenia (15%, 12%, 0%). Conclusion: IROF in combination with P and, in particular, C/P shows improved activity and acceptable tolerance compared to M/P in docetaxel-resistant HRPC. Patient accrual is complete as of Jan 2006, and final results will be presented. [Table: see text]

[Table: see text]

Phase II study of neoadjuvant docetaxel and androgen suppression (AS) plus radiation therapy (RT) for high-risk localized prostate cancer (HRLCaP)

4631

Background: Docetaxel increases survival in hormone-refractory prostate cancer and is active in hormone-sensitive disease. In HRLCaP, improvement upon AS plus RT is required, as many patients eventually develop metastases. This trial’s objective was to assess the tolerability of neoadjuvant docetaxel plus AS and RT in men with HRLCaP. Methods: Fifty-four men with newly diagnosed previously untreated HRLCaP were accrued to a Phase II single-arm, 2-stage, open-label study involving 7 Canadian centres. All were to receive 3 years of AS (LHRH-agonist + antiandrogen for 4 weeks). Chemotherapy started week 5. Twenty-four men received docetaxel 35 mg m2 iv weekly × 6 q8 weeks for 2 cycles, RT starting week 25. After protocol revision, 30 men received docetaxel 75 mg m2 iv q3 weekly for 4 cycles, RT starting week 21. The primary endpoint was unacceptable toxicity (UT), defined as ≥Grade 3 non-hematologic toxicity (except nausea/vomiting, tearing, short-term fatigue, and easily-controlled diarrhea), grade 4 thrombocytopenia, grade 4 neutropenia lasting >7 days, febrile neutropenia, or toxicity-related RT change (delay>2 weeks, >25% dose reduction). Results: Median age was 68 (49–79) years. Median iPSA was 19.15 (2.8–138) μg/L. Gleason Score and T-stage were ≥8 and ≥T3a in 70.4% and 42.6%, respectively. All patients have completed RT. Adverse events were as expected for docetaxel. UT occurred in 8 patients (14.8%), including 5 with qweekly docetaxel (Grade 3 acute RT-related genitourinary toxicity - 3, Grade 3 docetaxel hypersensitivity - 1, Grade 3 fatigue >2 weeks - 1) and 3 with q3 weekly docetaxel (Grade 3 acute RT-related genitourinary toxicity - 1, febrile neutropenia - 1, Grade 4 neutropenia >7 days - 1). The following table summarizes PSA response to neoadjuvant treatment. Conclusions: Neoadjuvant AS and docetaxel plus RT in men with HRLCaP appeared well tolerated. Patients will be followed for other outcomes. This approach will be tested in a phase 3 trial.

[Table: see text]

No significant financial relationships to disclose.

Factors influencing yields of progenitor cells for allogeneic transplantation: optimization of G-CSF dose, day of collection, and duration of leukapheresis

Mobilization of hematopoietic progenitor cells by G-CSF was attempted on 89 occasions in 85 healthy donors. Three dose ranges of G-CSF were chosen for analysis: low (4-7.4 micrograms/kg), intermediate (7.5-10 micrograms/kg) and high (> 10 micrograms/kg). A target blood level for apheresis of 20 x 10(6)/L CD34+ cells was reached by day 3 in 75 patients (84%) and by day 4 in all but 1 (99%). Target yields above 2.5 x 10(6)/kg for 75 unmanipulated transplants were exceeded in a single collection in 73 donors (97%). Correlation of CD34+ cell yields to blood CD34+ cell level before leukapheresis was moderate only (r2 = 0.32). There was close linear correlation between processed volume and cumulative CD34+ cell yield, with a median r2 value of 0.98 (range 0.74-1.00). Yields of CD34+ cells achieved on day 3 were significantly lower after the high dose than after the intermediate G-CSF dose (21 +/- 3 versus 29 +/- 6 x 10(6)/L blood processed, p = 0.03). After the low dose of G-CSF, yields on day 4 were higher than on day 3 (48 +/- 10 versus 22 +/- 4 x 10(6)/L blood processed, p = 0.01). There was no difference between day 3 and day 4 yields with the intermediate G-CSF dose. In 73 of 93 (78%) leukaphereses, the CD34+ cell yield was more than 100% of the estimated intravascular CD34+ cells at the beginning of collection and ranged up to 342%. These data indicate that a daily dose of 7.5-10 micrograms/kg G-CSF, given as a multiple of 300 and 480 micrograms ampoules, is a convenient regimen giving adequate yields from a single collection on day 3 or 4 in most donors. Measuring blood CD34+ cell levels is of limited value in predicting yields, but monitoring CD34+ cell yields during leukapheresis may help to minimize unnecessary or inefficient collection.