Citations

6036 Background: E3311 is a phase II randomized study of intermediate risk HPV+ OPC patients who underwent TOS by credentialed surgeons and were then treated by pathology-guided, deintensified post-operative treatment. Recent retrospective population data suggest that time to post-operative radiotherapy (PORT) > 6 weeks is associated with worse progression-free survival (PFS). Methods: We retrospectively analyzed demographics, pathologic characteristics, and oncologic outcomes in E3311 by time to initiation of PORT (short vs long, exploring both 6 and 7 weeks postop as the cutpoint). Binary and categorical variables were compared using a chi-square test (or a Fisher’s exact test for small sample sizes). Ordinal variables were compared using a Wilcoxon rank sum test. PFS and overall survival (OS) were estimated using the Kaplan-Meier method and compared using a log-rank test, which was stratified by intermediate- (Arms B/C) vs high-risk (Arm D). Results: Among 321 evaluable patients, the median time to initiation of PORT was 5.1 weeks (range 0.7-15.7); 5.0 (0.7-15.7) for Arm B, 5.1 (2.4-7.0) for Arm C, 5.6 (3.6-7.9) for Arm D. No significant difference in PFS or OS was observed whether PORT commenced by 6 or 7 weeks postoperatively, compared with longer time to initiation of PORT (p = 0.62 and 0.65, p = 0.30 and p = 0.41, respectively). 3-yr PFS rates were 93.5% (95% CI: 89.4%, 96.0%) among those treated ≤6 weeks, and 91.2% (95% CI: 81.4%, 95.9%) among those treated > 6 weeks; 3-yr OS rates were 96.1% (95% CI: 92.7%, 98.0%) among those treated ≤6 weeks, and 94.1% (95% CI: 84.9%, 97.8%) among those treated > 6 weeks. No significant differences in outcomes were observed between intermediate risk treatment arms (deintensified (50Gy) or standard dose (60Gy) RT). Additional demographic and pathologic characteristics, including primary site, margin status, histologic grade, stage, and extranodal extension were not significantly different between those with short vs long time to PORT, whether 6 or 7 weeks was used as the cutpoint. There were more T2 tumors in those treated > 7 weeks postop (84% vs. 49%, p = 0.007). PS = 1 patients were more numerous among those with shorter time to PORT (10% vs 0%, with the 7 week cutpoint). Conclusions: In contrast to retrospective NCDB data, intermediate- and high-risk HPV+ OPC patients enrolled on E3311 had favorable 3-yr PFS and OS rates that were not significantly worse when adjuvant therapy was started > 6 wks or > 7wks. These results argue against a survival advantage for initiation of PORT within 6 or 7 weeks for early-stage HPV+ OPC managed with high-quality transoral resection. The optimal time window to initiate PORT in HPV+ OPC patients remains to be determined. Clinical trial information: NCT01898494 .

4007 Background: Biliary tract cancer (BTC) is an aggressive malignancy with a poor prognosis, and current treatment options for advanced BTC are limited, with second-line therapy, FOLFOX and S-1 offering an objective response rate (ORR) of 5.0% and 7.5%, respectively. Up to 20% of BTCs overexpress human epidermal growth factor receptor 2 (HER2). Tucatinib (TUC) is a highly selective HER2-directed TKI approved for HER2-positive (HER2+) metastatic breast and colorectal cancer. Discussed here are the efficacy and safety results of TUC combined with Trastuzumab (Tras) in pts with previously treated HER2+ metastatic BTC. Methods: SGNTUC-019 (NCT04579380) is an open-label phase 2 basket study evaluating efficacy, safety, and tolerability of TUC and Tras in pts with HER2-altered solid tumors. Pts in the BTC cohort had been previously treated with and progressed after ≥1 line of systemic therapy for metastatic disease. Eligible pts had locally determined HER2+ (defined as HER2 overexpression determined by immunohistochemistry [IHC] 3+ or HER2 amplification determined by in situ hybridization assay or next-generation sequencing) metastatic BTC. Pts were treated on a 21-day cycle with TUC (300 mg orally twice a day) and Tras (8 mg/kg IV followed by 6 mg/kg every 3 wks). Disease status was determined based on RECIST v1.1 with assessments performed every 6 wks for 24 wks and every 12 wks thereafter. The primary endpoint is confirmed objective response rate (cORR) per investigator assessment. Secondary endpoints include overall survival (OS), disease control rate (DCR), duration of response (DOR), progression-free survival (PFS), and safety. Results: Thirty pts were enrolled in the BTC cohort as of data cutoff date of 30 Nov 2022. The median duration of follow-up was 8.3 months. cORR was 46.7% (90% CI, 30.8, 63.0), with 14 responses including 1 complete and 13 partial responses. Median DOR was 6.0 months (90% CI, 5.5, not estimable). DCR was 76.7% (n=23; 90% CI, 60.6, 88.5), and median PFS was 5.5 months (90% CI, 3.9, 8.1). At data cutoff, 13 (43.3%) patients had died, and the 12-months OS rate was 53.8% (90% CI, 35.2, 69.1%). Overall, the most common treatment-emergent adverse events (TEAEs) reported were pyrexia (43.3%) and diarrhea (40.0%). Grade ≥3 TEAEs were reported in 18 (60.0%) of 30 pts; however, only 6 (20.0%) and 2 (6.7%) of these pts had Grade ≥3 TEAEs related to TUC and Tras, respectively. Two (6.7%) pts discontinued TUC due to TEAEs, cholangitis and liver disorder. No deaths were due to TEAEs. Conclusions: The combination of TUC and Tras was well tolerated in pts with previously treated HER2+ metastatic BTC. The observed antitumor activity supports the combination of TUC and Tras as a future chemotherapy-free treatment option for this population with historically poor outcomes. Clinical trial information: NCT04579380 .

OBJECTIVE There are no commercially available hybrid closed-loop insulin delivery systems customized to achieve pregnancy-specific glucose targets in the U.S. This study aimed to evaluate the feasibility and performance of at-home use of a zone model predictive controller–based closed-loop insulin delivery system customized for pregnancies complicated by type 1 diabetes (CLC-P). RESEARCH DESIGN AND METHODS Pregnant women with type 1 diabetes using insulin pumps were enrolled in the second or early third trimester. After study sensor wear collecting run-in data on personal pump therapy and 2 days of supervised training, participants used CLC-P targeting 80–110 mg/dL during the day and 80–100 mg/dL overnight running on an unlocked smartphone at home. Meals and activities were unrestricted throughout the trial. The primary outcome was the continuous glucose monitoring percentage of time in the target range 63–140 mg/dL versus run-in. RESULTS Ten participants (HbA1c 5.8 ± 0.6%) used the system from mean gestational age of 23.7 ± 3.5 weeks. Mean percentage time in range increased 14.1 percentage points, equivalent to 3.4 h per day, compared with run-in (run-in 64.5 ± 16.3% versus CLC-P 78.6 ± 9.2%; P = 0.002). During CLC-P use, there was significant decrease in both time over 140 mg/dL (P = 0.033) and the hypoglycemic ranges of less than 63 mg/dL and 54 mg/dL (P = 0.037 for both). Nine participants exceeded consensus goals of above 70% time in range during CLC-P use. CONCLUSIONS The results show that the extended use of CLC-P at home until delivery is feasible. Larger, randomized studies are needed to further evaluate system efficacy and pregnancy outcomes.

Background: An open Achilles tendon repair is performed in patients who have suffered an acute rupture. All patients with this injury should be counseled on their treatment options, which include open operative repair and functional rehabilitation. We prefer the use of an open repair in high-level athletes and those who have delayed presentation. Typically, this injury—and the resulting open repair—are seen in young or middle-aged patients as well as athletes. Operative repair of a ruptured Achilles tendon is associated with a much faster return to activity/sport when compared with nonoperative alternatives. This surgical procedure is especially useful in allowing this patient population to return to their previous activity level and functional capacity as quickly as possible. Description: Open repair of a ruptured Achilles tendon begins with a 6 to 8-cm incision over the posteromedial aspect of the lower leg. Superficial and deep dissections are performed until the 2 ends of the ruptured tendon are identified. Adhesions are debrided to adequately mobilize and define the proximal and distal segments of the tendon. With use of a fiber tape suture, a modified locking Bunnell stitch is utilized to secure both ends. The fiber tape is tied securely, and the repair is reinforced with Vicryl suture (Ethicon). Once the tendon is repaired, the paratenon layer is identified and repaired with a running 0 or 2-0 Vicryl suture. This is an important step to minimize postoperative wound complications. The wound is then closed, and the extremity is splinted in maximum plantar flexion. Alternatives: Alternative treatments include minimally invasive surgical techniques such as percutaneous Achilles tendon repair and nonoperative treatment with functional rehabilitation, which can provide excellent outcomes but can also lead to a slight decrease in explosiveness as the patient returns to sport 1,2 . Rationale: Nonoperative and operative treatment of Achilles tendon rupture can both result in excellent patient outcomes. Appropriate patient selection is critical. Younger patients hoping to return to more highly competitive athletics should consider operative repair 3 . Possible differences have been identified in peak torque when comparing operative versus nonoperative treatment, with patients who had undergone operative repair having greater peak torque (i.e., explosiveness) 2 . Otherwise, findings are similar between treatment options as long as the patients meet the criteria for nonoperative treatment. Expected Outcomes: Overall, the scientific literature demonstrates that the functional outcomes following operative repair are good to excellent. In a study by Hsu et al. 4 , 88% of patients were able to return to their baseline level of activity by 5 months postoperatively, with a complication rate of 10.6% and no reruptures. In a recent meta-analysis by Meulenkamp et al. 5 , the authors found that operative repair of Achilles tendon rupture was associated with a reduced risk of rerupture compared with primary immobilization (i.e., conventional cast immobilization with delayed weight-bearing for at least 6 weeks only). However, open surgical repair, minimally invasive repair, and functional rehabilitation all had similar risk of rerupture 5 . In a review by Ochen et al. 6 that analyzed 29 studies with a total of 15,862 patients, operative repair was associated with a significantly lower risk of rerupture compared with nonoperative treatment (2.3% versus 3.9%, respectively). However, operative treatment was also associated with a significantly higher complication rate compared with nonoperative treatment (4.9% versus 1.6%, respectively) 6 . Finally, in a meta-analysis by Soroceanu et al. 7 , the authors found that if early range-of-motion protocols and functional rehabilitation were utilized, operative and nonoperative treatment resulted in similar outcomes and equivalent rates of rerupture. Important Tips: To prevent rerupture of an Achilles tendon, remind patients to engage in adequate stretching and warming prior to physical activity. Palpate and locate the tendon defect prior to making the first incision. Immobilize the ankle joint in a splint for 2 weeks postoperatively in maximum plantar flexion. Pitfalls include: ○ Poor suture management leading to tangling in the repair. ○ Undertensioning or overtensioning of the repair, which can be avoided by sterilely draping out both legs and checking resting tension intraoperatively. ○ Failure to close the paratenon, causing scarring of the skin or surrounding tissues, which can be avoided by making a relieving incision on the deep surface of the paratenon. ○ Leaving suture knots on the dorsal side of the repair that may aggravate the skin. Acronyms & Abbreviations: MRI = magnetic resonance imaging ESU = electrosurgical unit

6077 Background: E3311 is a phase II randomized study which showed favorable outcomes among intermediate (INT) risk HPV+ OPC patients (pts) who underwent TOS followed by pathology-guided or adapted, deintensified adjuvant treatment. Among HPV+ pts treated with definitive chemoradiation, survival outcomes are worse among those who smoked > 10 pack years (pk-yrs). Methods: We retrospectively analyzed demographics, pathologic results, and efficacy outcomes from E3311 by smoking group (current (C) vs. former (F) and > 10 vs. ≤10 pk-yrs – the latter a pre-specified stratification factor for INT patients). Binary and categorical variables were compared using a chi-square test (or Fisher’s exact test for small sample sizes). Ordinal variables were compared using a Wilcoxon rank sum test. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method and compared using a log-rank test. Results: Among 359 evaluable pts, performance status (PS) was significantly worse for pts with > 10 pk-yrs vs. ≤10 pk-yrs (15.4% vs. 7.9% with PS of 1, p = 0.034). Primary site, margin status, histologic grade, stage, and extranodal extension were not significantly different between the groups of > 10 vs. ≤10 pk-yrs. Smoking status (F vs. C) was available for 182 pts with a history of smoking. Slightly more C vs. F smokers had tonsil as primary site (79.5% vs. 65.0%, p = 0.09). Positive margins were significantly more frequent among C smokers (10.3% vs. 2.1%; p = 0.029). Overall, there were no significant differences in PFS (p = 0.55) or OS (p = 0.94), comparing those with > 10 vs. ≤10 pk-yrs, or comparing C vs. F smokers (p = 0.76, p = 0.82, respectively). Similarly, no significant differences were observed within the treatment arms. (Table 1) Conclusions: In this analysis of smoking status in E3311, INT risk HPV+ OPC pts who are C smokers or have a history of > 10 pk-yrs had favorable 3-yr PFS and OS rates that were not significantly worse than those with < 10 pk-yrs history. This data represents the first treatment approach for HPV+ OPC in which outcomes were not influenced by smoking status. Clinical trial information: NCT01898494. [Table: see text]

Background: Automated insulin delivery (AID) systems have proven effective in increasing time-in-range during both clinical trials and real-world use. Further improvements in outcomes for single-hormone (insulin only) AID may be limited by suboptimal insulin delivery settings. Methods: Adults (≥18 years of age) with type 1 diabetes were randomized to either sensor-augmented pump (SAP) (inclusive of predictive low-glucose suspend) or adaptive zone model predictive control AID for 13 weeks, then crossed over to the other arm. Each week, the AID insulin delivery settings were sequentially and automatically updated by an adaptation system running on the study phone. Primary outcome was sensor glucose time-in-range 70–180 mg/dL, with noninferiority in percent time below 54 mg/dL as a hierarchical outcome. Results: Thirty-five participants completed the trial (mean age 39 ± 16 years, HbA1c at enrollment 6.9% ± 1.0%). Mean time-in-range 70–180 mg/dL was 66% with SAP versus 69% with AID (mean adjusted difference +2% [95% confidence interval: −1% to +6%], P = 0.22). Median time <70 mg/dL improved from 3.0% with SAP to 1.6% with AID (−1.5% [−2.4% to −0.5%], P = 0.002). The adaptation system decreased initial basal rates by a median of 4% (−8%, 16%) and increased initial carbohydrate ratios by a median of 45% (32%, 59%) after 13 weeks. Conclusions: Automated adaptation of insulin delivery settings with AID use did not significantly improve time-in-range in this very well-controlled population. Additional study and further refinement of the adaptation system are needed, especially in populations with differing degrees of baseline glycemic control, who may show larger benefits from adaptation.

Background: We investigated the potential benefits of automated insulin delivery (AID) among individuals with type 1 diabetes (T1D) in sub-populations of baseline device use determined by continuous glucose monitor (CGM) use status and insulin delivery via multiple daily injections (MDI) or insulin pump. Materials and Methods: In a six-month randomized, multicenter trial, 168 individuals were assigned to closed-loop control (CLC, Control-IQ, Tandem Diabetes Care), or sensor-augmented pump (SAP) therapy. The trial included a two- to eight-week run-in phase to train participants on study devices. The participants were stratified into four subgroups: insulin pump and CGM (pump+CGM), pump-only, MDI and CGM (MDI+CGM), and MDI users without CGM (MDI-only) users. We compared glycemic outcomes among four subgroups. Results: At baseline, 61% were pump+CGM users, 18% pump-only users, 10% MDI+CGM users, and 11% MDI-only users. Mean time in range 70-180 mg/dL (TIR) improved from baseline in the four subgroups using CLC: pump+CGM, 62% to 73%; pump-only, 61% to 70%; MDI+CGM, 54% to 68%; and MDI-only, 61% to 69%. The reduction in time below 70 mg/dL from baseline was comparable among the four subgroups. No interaction effect was detected with baseline device use for TIR ( P = .67) or time below ( P = .77). On the System Usability Questionnaire, scores were high at 26 weeks for all subgroups: pump+CGM: 87.2 ± 12.1, pump-only: 89.4 ± 8.2, MDI+CGM 87.2 ± 9.3, MDI: 78.1 ± 15. Conclusions: There was a consistent benefit in patients with T1D when using CLC, regardless of baseline insulin delivery modality or CGM use. These data suggest that this CLC system can be considered across a wide range of patients.

Objectives: To determine whether 2 different methods of post-operative head and neck free flap monitoring affect flap failure and complication rates. Methods: A retrospective chart review of 803 free flaps performed for head and neck reconstruction by the same microvascular surgeon between July 2013 and July 2020 at 2 separate hospitals within the same healthcare system. Four-hundred ten free flaps (51%) were performed at Hospital A, a medical center where flap checks were performed at frequent, scheduled intervals by in-house resident physicians and nurses; 393 free flaps (49%) were performed at Hospital B, a medical center where flap checks were performed regularly by nursing staff with resident physician evaluation as needed. Total free flap failure, partial free flap failure, and complications (consisting of wound infection, fistula, and reoperation within 1 month) were assessed. Results: There were no significant differences between Hospitals A and B when comparing rates of total free flap failure, partial free flap failure, complication, or re-operation ( P = .27, P = .66, P = .65, P = .29, respectively). There were no significant differences in urgent re-operation rates for flap compromise secondary to thrombosis and hematoma ( P = .54). Conclusions: In our series, free flap outcomes did not vary based on the degree of flap monitoring by resident physicians. This data supports the ability of a high-volume, well-trained, nursing-led flap monitoring program to detect flap compromise in an efficient fashion while limiting resident physician obligations in the age of resident duty hour restrictions.

Background: Pregnancies in type 1 diabetes are high risk, and data in the United States are limited regarding continuous glucose monitoring (CGM)-based hypoglycemia throughout pregnancy while on sensor-augmented insulin pump therapy. Materials and Methods: Pregnant women with type 1 diabetes in the LOIS-P Study (Longitudinal Observation of Insulin use and glucose Sensor metrics in Pregnant women with type 1 diabetes using continuous glucose monitors and insulin pumps) were enrolled before 17 weeks gestation at three U.S. centers and we used their personal insulin pump and a study Dexcom G6 CGM. We analyzed data of 25 pregnant women for CGM hypoglycemia based on international consensus guidelines for percentage time <63 and 54 mg/dL, hypoglycemic events and prolonged hypoglycemia events for 24-h, daytime, and overnight periods, and severe hypoglycemia (SH) episodes. Results: For a 24-h period, biweekly median percentage of time <63 mg/dL ranged from 0.8% at biweek 4–5 to 3.7% at biweek 14–15 with high variability throughout pregnancy. Median percentage of time <63 and 54 mg/dL was higher overnight than daytime ( P < 0.01). Hypoglycemic events occurred throughout the pregnancy, ranged 1–4 events per 2 weeks, significantly decreased after the 20th week, and occurred predominantly during daytime ( P < 0.01). For overnight period, hypoglycemia and events were more concentrated from 12 to 3 am. Seven prolonged hypoglycemia events without any associated SH occurred in four participants (16%), primarily overnight. Three participants experienced a single episode of SH. Conclusions: Our results suggest a higher overall risk of hypoglycemia throughout pregnancy during the overnight period with continued daytime risk of hypoglycemic events in pregnancies complicated by type 1 diabetes.