BackgroundRadiation therapy (RT) dose for inoperable pancreatic ductal adenocarcinoma (PDAC) has historically been non-ablative to avoid injuring gastrointestinal (GI) organs at risk (OARs). Accruing data suggest that dose escalation, in select patients, may significantly improve clinical outcomes. Early results of ablative stereotactic magnetic resonance image-guided adaptive radiation therapy (A-SMART) have been encouraging, although long-term outcomes are not well understood.MethodsA single institution retrospective analysis was performed of inoperable non-metastatic PDAC patients who received induction chemotherapy then 5-fraction A-SMART on a 0.35T-MR Linac from 2018-2021.ResultsSixty-two patients were evaluated with a median age of 66 years (range 35-91) and nearly all achieved Eastern Cooperative Oncology Group (ECOG) performance status 0-1 (96.8%). Locally advanced disease was common (72.6%), otherwise borderline resectable (22.6%), or medically inoperable (4.8%). All received induction chemotherapy for a median 4.2 months (range, 0.2-13.3) most commonly FOLFIRINOX (n=43; 69.4%). Median prescribed dose was 50 Gy (range 40-50); median biologically effective dose (BED10) was 100 Gy10. The median local control (LC), progression-free survival (PFS), and overall survival (OS) from diagnosis were not reached, 20 months, and 23 months, respectively. Also, 2-year LC, PFS, and OS were 68.8%, 40.0%, and 45.5%, respectively. Acute and late grade 3+ toxicity rates were 4.8% and 4.8%, respectively.ConclusionsTo our knowledge, this is the largest series of induction chemotherapy followed by ablative 5-fraction SMART delivered on an MR Linac for inoperable PDAC. The potential for this novel treatment strategy is to achieve long-term LC and OS, compared to chemotherapy alone, and warrants prospective evaluation.

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The article " Â-genus on non-spin manifolds with S 1 actions and the classification of positive quaternion-Kähler 12-manifolds" [3] contains an error in Lemma 2 of Part I, since an assumption on the finiteness of the second homotopy group is not sufficient to reach the desired conclusion. This error stems from an incorrect application of Theorem V in [2], and we thank M. Amann and A. Dessai for pointing it out (see [1]).An additional hypothesis of finiteness of the fourth homotopy group proves to be enough to correct Lemma 2 and, therefore, Theorems 1 and 3 that depend on it. We also thank M. Amann and A. Dessai [1] for this observation.On the other hand, Theorem 2 depends on the original version of Theorem 1 and, therefore, its proof is not complete. We note that the fourth homotopy group of the real Grassmannian of oriented 4-planes in R 7 , a positive quaternion-Kähler 12-manifold, is not finite.

A retrospective review was undertaken of 126 consecutive craniofacial procedures involving a transcranial component, performed at the Children's Medical Center at Dallas, between 1990 and 1994. Standard postoperative axillary temperature measurements were recorded until discharge. Age at surgery of less than 24 months correlated very strongly with a postoperative temperature of greater than 38 degrees C (r = -0.92). The incidence of postoperative fever was high in all age groups, yet there was still a significant difference between the group younger than 2 years and the group in which surgery was performed after the age of 2 years across all postoperative temperature ranges, from >38 degrees C to >39.5 degrees C (p < 0.001, chi-square test). The white blood cell count was elevated above the age-related normal in 67 percent of febrile patients. There was no correlation between type or duration of surgical procedure, length of intensive care or hospital stay, or the need for blood transfusion and the development of a significant postoperative fever. There were minor infectious complications in four patients (3 percent), only one of which was a wound problem related to the surgery. All infectious complications were easily identifiable clinically. There was no mortality or serious infections. The development of postoperative fever, and an elevated white blood cell count, is to be expected in pediatric patients undergoing craniofacial procedures. The routine laboratory investigation of postoperative fever in pediatric craniofacial patients under 2 years of age without procedures involving transgression of the paranasal sinuses is not warranted unless there are associated clinical indicators.