Mapping of Recurrence Sites Following Adjuvant or Salvage Radiotherapy for Prostate Cancer Patients

IntroductionAlthough salvage and adjuvant radiotherapy (RT) are effective in prostate cancer (PC) patients, 30%–40% of men will have disease progression. The objective was to describe the pattern of recurrence in PC patients with biochemical failure (BF) following postoperative RT.MethodsWe retrospectively analyzed 935 PC patients treated from 2009 to 2019 with adjuvant or salvage RT at the Institut de Cancérologie de l’Ouest. Of these, 205 (22%) developed BF of whom 166 underwent imaging. Patients with identified radiologic failure prior any specific treatment were included to determine the site of relapse categorized as local (L)-only, locoregional (LR), or metastatic (M) recurrence. Main disease characteristics and RT fields were examined in relation to sites of recurrence.ResultsOne hundred forty-one patients were identified with 244 sites of failure on imaging. Of these, 108 patients had received RT to the PB alone and 33 RT to the PB and pelvic lymph nodes (PB+PLN). Androgen-deprivation therapy was used concomitantly in 50 patients (35%). The median PSA at imaging was 1.6 ng/ml (range, 0–86.7). In all, 74 patients (52%) had M disease (44% in the PB group and 79% in the PB+PLN group), 61 (43%) had LR failure (52% in the PB alone group and 15% in the PB+PLN group), and six (4%) had L-only failure, at a median of 26.7 months (range, 5–110.3) from RT. Metastases were in extra-pelvic LN (37 (15%)), bones (66 (27%)), and visceral organs (eight (3%)). Fifty-three (48%) of the pelvic LN failures in the PB group would have been encompassed by standard PLN RT volume.ConclusionWe found that most patients evaluated for BF after postoperative RT recurred outside the RT field. Isolated pelvic nodal failure was rare in those receiving RT to the PB+PLN but accounted for half of failures in those receiving PB alone RT. Imaging directed salvage treatment could be helpful to personalize radiation therapy plan.

Liberal-Democratic Torture

This chapter gives a primer on liberal-democratic torture. A brief summary of the historical record shows that liberal democracies have repeatedly engaged in “stealth” coercive interrogation, which the chapter argues usually qualifies as torture by the UN Convention against Torture’s standard definition. What can explain the pattern of recurrence that emerges? Previous work is a useful starting point but leaves important questions unanswered. Lack of monitoring can invite norm violations, but torture is not always hidden. Racism and anger make states and individuals more likely to torture, but they do not tell us why torture often occurs in conjunction with demands for intelligence. Realist and rational choice arguments help to explain the frequent connection between torture and intelligence needs, but they fail to address critical lurking puzzles: Why do people believe torture works? And how do torturers justify these norm-breaking deeds to themselves and others?

P-OGC59 Pattern of recurrence following neoadjuvant treatment and two-stage oesophagectomy for oesophageal/junctional adenocarcinoma: 10-year results from a high-volume centre

Background Disease recurrence remains high following oesophagectomy for oesophageal and junctional adenocarcinoma in spite of the incremental gains from improved neoadjuvant treatment (NAT). Follow-up remains important for the detection and treatment of recurrence, although the optimum surveillance strategy remains undefined. Recurrence after treatment can occur locoregionally, distantly, or a combination of both. This retrospective review of a single, high-volume centre’s 10-year experience has sought to determine the pattern of recurrence in those who have received curative NAT followed by two-stage subtotal oesophagectomy (2S-STO) for oesophageal and junctional adenocarcinoma. Methods A retrospective analysis was performed on a cohort of patients from a high-volume, single centre between January 2009 and January 2019 who had confirmed disease recurrence after receiving NAT and 2S-STO for either oesophageal or junctional (Siewert I/II) adenocarcinoma. The Unit’s prospectively collected cancer database was utilised as well as patients’ notes to determine the pattern of recurrence seen in this cohort. Patients receiving a three-stage or transhiatal oesophagectomy for any cause, or those diagnosed with squamous cell carcinoma were excluded. Results 215 patients were identified with recurrence following NAT and 2S-STO for oesophageal/junctional adenocarcinoma within the 10-year period. The median age was 69 (range 23-85) with 67% being male and 33% female. The median time to diagnosis of recurrence was 13 months following surgery. 87 (40%) patients were diagnosed with locoregional recurrence, with the commonest pattern being in mediastinal or abdominal lymph nodes, followed by peritoneal disease. 62 (29%) patients were diagnosed with distant recurrence, with the vast majority being in the liver or lungs. 66 (31%) patients had evidence of both locoregional and distant spread at diagnosis of recurrence. Conclusions The incidence of recurrence following curative treatment for oesophageal and junctional adenocarcinoma remains high. Locoregional disease appears to be the commonest pattern of recurrence as identified in this study, which would confirm spread predominates via the lymphatic and transcoelomic routes. Liver and lung remain the commonest sites for haematogenous spread, although other sites include adrenal, brain and bone. Although the optimum follow-up strategy remains undefined in such patients, timely investigation of symptoms is required for early diagnosis so as to optimise the benefits of palliative treatment.

Pattern of Recurrence of Glioblastoma Versus Grade 4 IDH-Mutant Astrocytoma Following Chemoradiation

Purpose To quantitatively compare the recurrence pattern of glioblastoma (IDH-wild type) versus grade 4 IDH-mutant astrocytoma (herein referred to as wtIDH and mutIDH, respectively) following primary chemoradiation. Methods Twenty-two wtIDH and 22 mutIDH patients matched by sex, extent of resection, and corpus callosum involvement were enrolled. The recurrent gross tumor volume (rGTV) was compared with both the gross tumor volume (GTV) and clinical target volume (CTV) from radiotherapy planning. Failure patterns were quantified by the incidence and volume of the rGTV outside the GTV and CTV, and positional differences of the rGTV centroid from the GTV and CTV. Results The GTV was smaller in wtIDH compared to the mutIDH group (mean±SD: 46.5±26.0 cm3 v. 72.2±45.4 cm3, p=0.026). The rGTV was 10.7±26.9 cm3 and 46.9±55.0 cm3 smaller than the GTV for the same groups (p=0.018). The rGTV extended outside the GTV in 22 (100%) and 15 (68%) (p=0.009) of wtIDH and mutIDH patients, respectively; however, the volume of rGTV outside the GTV was not significantly different (12.4±16.1 cm3 vs. 8.4±14.2 cm3, p=0.443). The rGTV metrics extending outside the CTV was not different between the groups. The rGTV centroid was within 5.7 mm of the closest GTV edge for 21 (95%) and 22 (100%) of wtIDH and mutIDH patients, respectively. Conclusion The rGTV extended beyond the GTV less often in mutIDH patients, suggesting limited margin radiotherapy could be beneficial in this group. The results support the study of small margin adaptive radiotherapy per the ongoing UNITED MR-Linac 5 mm CTV trial (NCT04726397).

681 PATTERN OF RECURRENCE IN PATIENTS WITH A PATHOLOGICALLY COMPLETE RESPONSE AFTER NEOADJUVANT CHEMORADIOTHERAPY AND SURGERY FOR OESOPHAGEAL CANCER

Neoadjuvant chemoradiotherapy (nCRT) and surgery is a widely used treatment for locally advanced resectable oesophageal cancer, with 20 and 50% of patients having a pathological complete response (pCR). Disease, however, still recurs in 20–30% of these patients. The aim of this study was to assess the pattern of recurrence in patients with pCR after nCRT and surgery. Methods All patients with pCR after neoadjuvant chemoradiotherapy and surgery included in the phase II and III ChemoRadiotherapy for Oesophageal followed by Surgery Study (CROSS) trials (April 2001—March 2009) and after the CROSS trials (September 2009—October 2017) were identified. The site of recurrence was compared to the applied radiation and surgical fields. Outcomes were median time to recurrence, overall and progression-free survivals. Results A total of 141 patients with a median follow-up of 100 (interquartile range [IQR] 64–134) months were included. Some 29 of 141 patients (21%) developed recurrence. Of these, four (14%) had isolated locoregional recurrence, 15 (52%) distant recurrence only and ten (34%) had both locoregional and distant recurrence. Among the 14 patients with locoregional recurrences, five were within the radiation field, seven outside the radiation field and two at the border. Median (IQR) time to recurrence was 24 (10–62) months. The 5-year overall survival was 74% and recurrence-free survival 70%. Conclusion Despite good overall survival, recurrence still occurred in 21% of patients. Most recurrences were distant, outside the radiation and surgical fields.