Radiation necrosis after radiation therapy treatment of brain metastases: A computational approach.

Metastasis is the process through which cancer cells break away from a primary tumor, travel through the blood or lymph system, and form new tumors in distant tissues. One of the preferred sites for metastatic dissemination is the brain, affecting more than 20% of all cancer patients. This figure is increasing steadily due to improvements in treatments of primary tumors. Stereotactic radiosurgery (SRS) is one of the main treatment options for patients with a small or moderate number of brain metastases (BMs). A frequent adverse event of SRS is radiation necrosis (RN), an inflammatory condition caused by late normal tissue cell death. A major diagnostic problem is that RNs are difficult to distinguish from BM recurrences, due to their similarities on standard magnetic resonance images (MRIs). However, this distinction is key to choosing the best therapeutic approach since RNs resolve often without further interventions, while relapsing BMs may require open brain surgery. Recent research has shown that RNs have a faster growth dynamics than recurrent BMs, providing a way to differentiate the two entities, but no mechanistic explanation has been provided for those observations. In this study, computational frameworks were developed based on mathematical models of increasing complexity, providing mechanistic explanations for the differential growth dynamics of BMs relapse versus RN events and explaining the observed clinical phenomenology. Simulated tumor relapses were found to have growth exponents substantially smaller than the group in which there was inflammation due to damage induced by SRS to normal brain tissue adjacent to the BMs, thus leading to RN. ROC curves with the synthetic data had an optimal threshold that maximized the sensitivity and specificity values for a growth exponent ß* = 1.05, very close to that observed in patient datasets.

Can low-dose intravenous bevacizumab be as effective as high-dose bevacizumab for cerebral radiation necrosis?

Although intravenous bevacizumab (IVBEV) is the most promising treatment for cerebral radiation necrosis (CRN), there is no conclusion on the optimal dosage. Our retrospective study aimed to compare the efficacy and safety of high-dose with low-dose IVBEV in treating CRN associated with radiotherapy for brain metastases (BMs). This paper describes 75 patients who were diagnosed with CRN secondary to radiotherapy for BMs, treated with low-dose or high-dose IVBEV and followed up for a minimum of 6 months. The clinical data collected for this study include changes in brain MRI, clinical symptoms, and corticosteroid usage before, during, and after IVBEV treatment. At the 3-month mark following administration of IVBEV, a comparison of two groups revealed that the median percentage decreases in CRN volume on T2-weighted fluid-attenuated inversion recovery and T1-weighted gadolinium contrast-enhanced image (T1CE), as well as the signal ratio reduction on T1CE, were 65.8% versus 64.8% (p = 0.860), 41.2% versus 51.9% (p = 0.396), and 37.4% versus 35.1% (p = 0.271), respectively. Similarly, at 6 months post-IVBEV, the median percentage reductions of the aforementioned parameters were 59.5% versus 62.0% (p = 0.757), 39.1% versus 31.3% (p = 0.851), and 35.4% versus 28.2% (p = 0.083), respectively. Notably, the incidence of grade ≥3 adverse events was higher in the high-dose group (n = 4, 9.8%) than in the low-dose group (n = 0). Among patients with CRN secondary to radiotherapy for BMs, the administration of high-dose IVBEV did not demonstrate superiority over low-dose IVBEV. Moreover, the use of high-dose IVBEV was associated with a higher incidence of grade ≥3 adverse events compared with low-dose IVBEV.

Pre-operative vs. post-operative stereotactic radiosurgery for operative metastatic brain tumors: study protocol for a phase III clinical trial.

BACKGROUND AND OBJECTIVES: Almost one third of cancer patients in the United States will develop brain metastases on an annual basis. Surgical resection is indicated in the setting of brain metastases for reasons, such as maximizing local control in select patients, decompression of mass effect, and/or tissue diagnosis. The current standard of care following resection of a brain metastasis has shifted from whole brain radiation therapy to post-operative stereotactic radiosurgery (SRS). However, there is a significant rate of local recurrence within one year of postoperative SRS. Emerging retrospective and prospective data suggest pre-operative SRS is a safe and potentially effective treatment paradigm for surgical brain metastases. This trial intends to determine, for patients with an indication for resection of a brain metastasis, whether there is an increase in the time to a composite endpoint of adverse outcomes; including the first occurrence of either: local recurrence, leptomeningeal disease, or symptomatic radiation brain necrosis - in patients who receive pre-operative SRS as compared to patients who receive post-operative SRS. METHODS: This randomized phase III clinical trial compares pre-operative with post-operative SRS for brain metastases. A dynamic random allocation procedure will allocate an equal number of patients to each arm: pre-operative SRS followed by surgery or surgery followed by post-operative SRS. EXPECTED OUTCOMES: If pre-operative SRS improves outcomes relative to post-operative SRS, this will establish pre-operative SRS as superior. If post-operative SRS proves superior to pre-operative SRS, it will remain a standard of care and halt the increasing utilization of pre-operative SRS. If there is no difference in pre- versus post-operative SRS, then pre-operative SRS may still be preferred, given patient convenience and the potential for a condensed timeline. DISCUSSION: Emerging retrospective and prospective data have demonstrated some benefits of pre-op SRS vs. post-op SRS. This study will show whether there is an increase in the time to the composite endpoint. Additionally, the study will compare overall survival; patient-reported outcomes; morbidity; completion of planned therapies; time to systemic therapy; time to regional progression; time to CNS progression; time to subsequent treatment; rate of radiation necrosis; rate of local recurrence; and rate of leptomeningeal disease. TRIAL REGISTRATION NUMBER: NCT03750227 (Registration date: 21/11/2018).

Novel powered 5.0-mm endoscopic debridement catheter for endoscopic transmural necrosectomy of pancreatic walled-off necrosis: a case series of consecutive patients from a tertiary referral center (with video).

BACKGROUND AND AIMS: EUS-guided drainage and, if required, endoscopic necrosectomy (EN) has become the criterion standard for the treatment of pancreatic walled-off necrosis (WON). A dedicated powered endoscopic debridement system, the EndoRotor (Interscope Inc, Northbridge, Mass, USA), has been introduced as an alternative to snare necrosectomy. This study evaluates the novel EndoRotor catheter, NecroMax 6.0 (Interscope Inc, Whitinsville, Mass, USA), for EN in patients with WON. METHODS: This single-center retrospective case series included consecutive patients with WON treated with the NecroMax 6.0 catheter. Safety, ability to perform EN, and clinical resolution were evaluated. RESULTS: Twenty patients underwent 30 EN procedures with the NecroMax 6.0 catheter. One suspected device-related adverse event was observed (3.3%). In 1 procedure, EN could not be performed because of excessive bending of the endoscope. Eighteen patients (90.0%) achieved clinical resolution. CONCLUSIONS: EN with the NecroMax 6.0 catheter was technically feasible in 96.7% of patients with a low rate of adverse events.

Comparative analysis of bevacizumab and LITT for treating radiation necrosis in previously radiated CNS neoplasms: a systematic review and meta-analysis.

PURPOSE: Radiation necrosis (RN) is a local inflammatory reaction that arises in response to radiation injury and may cause significant morbidity. This study aims to evaluate and compare the efficacy of bevacizumab and laser interstitial thermal therapy (LITT) in treating RN in patients with previously radiated central nervous system (CNS) neoplasms. METHODS: PubMed, Cochrane, Scopus, and EMBASE databases were screened. Studies of patients with radiation necrosis from primary or secondary brain tumors were included. Indirect meta-analysis with random-effect modeling was performed to compare clinical and radiological outcomes. RESULTS: Twenty-four studies were included with 210 patients in the bevacizumab group and 337 patients in the LITT group. Bevacizumab demonstrated symptomatic improvement/stability in 87.7% of cases, radiological improvement/stability in 86.2%, and steroid wean-off in 45%. LITT exhibited symptomatic improvement/stability in 71.2%, radiological improvement/stability in 64.7%, and steroid wean-off in 62.4%. Comparative analysis revealed statistically significant differences favoring bevacizumab in symptomatic improvement/stability (p = 0.02), while no significant differences were observed in radiological improvement/stability (p = 0.27) or steroid wean-off (p = 0.90). The rates of adverse reactions were 11.2% for bevacizumab and 14.9% for LITT (p = 0.66), with the majority being grade 2 or lower (72.2% for bevacizumab and 62.5% for LITT). CONCLUSION: Both bevacizumab and LITT exhibited favorable clinical and radiological outcomes in managing RN. Bevacizumab was found to be associated with better symptomatic control compared to LITT. Patient-, diagnosis- and lesion-related factors should be considered when choosing the ideal treatment modality for RN to enhance overall patient outcomes.

Plastic pigtail vs lumen-apposing metal stents for drainage of walled-off necrosis (PROMETHEUS study): an open-label, multicenter randomized trial.

BACKGROUND: Lumen-apposing metal stents (LAMS) have displaced double-pigtail plastic stents (DPS) as the standard treatment for walled-off necrosis (WON),ß but evidence for exclusively using LAMS is limited. We aimed to assess whether the theoretical benefit of LAMS was superior to DPS. METHODS: This multicenter, open-label, randomized trial was carried out in 9 tertiary hospitals. Between June 2017, and Oct 2020, we screened 99 patients with symptomatic WON, of whom 64 were enrolled and randomly assigned to the DPS group (n = 31) or the LAMS group (n = 33). The primary outcome was short-term (4-weeks) clinical success determined by the reduction of collection. Secondary endpoints included long-term clinical success, hospitalization, procedure duration, recurrence, safety, and costs. Analyses were by intention-to-treat. CLINICALTRIALS: gov, NCT03100578. RESULTS: A similar clinical success rate in the short term (RR, 1.41; 95% CI 0.88-2.25; p = 0.218) and in the long term (RR, 1.2; 95% CI 0.92-1.58; p = 0.291) was observed between both groups. Procedure duration was significantly shorter in the LAMS group (35 vs. 45-min, p = 0.003). The hospital admission after the index procedure (median difference, - 10 [95% CI - 17.5, - 1]; p = 0.077) and global hospitalization (median difference - 4 [95% CI - 33, 25.51]; p = 0.82) were similar between both groups. Reported stent-related adverse events were similar for the two groups (36 vs.45% in LAMS vs. DPS), except for de novo fever, which was significantly 26% lower in LAMS (RR, 0.26 [0.08-0.83], p = 0.015). CONCLUSIONS: The clinical superiority of LAMS over DPS for WON therapy was not proved, with similar clinical success, hospital stay and similar safety profile between both groups, yet a significant reduction in procedure time was observed. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov, NCT03100578.

Two cases of small bowel necrosis due to intussusception secondary to abnormal proliferation of intestinal Peyer's patches in infants after MMR vaccination.

BACKGROUND: Intussusception is one of the most common acute abdominal conditions in pediatric patients, and if left untreated, it may result in intestinal necrosis and even death. The etiology of the disease is unknown and may be related to a variety of factors, and there are only limited reports of small bowel necrosis secondary to abnormal Peyer's node hyperplasia after MMR vaccination. CASE PRESENTATION: In this report, we present two infants who had an abnormal proliferation of Peyer's nodes secondary to intussusception eventually leading to small bowel necrosis after MMR vaccination. CONCLUSIONS: Intestinal necrosis and infectious shock are the most common causes of infant mortality, and early detection and management are critical.

Clinical outcomes of perforator-based propeller flaps versus free flaps in soft tissue reconstruction for lower leg and foot trauma: a retrospective single-centre comparative study.

BACKGROUND: The efficacy and safety of perforator-based propeller flaps (PPF) versus free flaps (FF) in traumatic lower leg and foot reconstructions are debated. PPFs are perceived as simpler due to advantages like avoiding microsurgery, but concerns about complications, such as flap congestion and necrosis, persist. This study aimed to compare outcomes of PPF and FF in trauma-related distal lower extremity soft tissue reconstruction. METHODS: We retrospectively studied 38 flaps in 33 patients who underwent lower leg and foot soft tissue reconstruction due to trauma at our hospital from 2015 until 2022. Flap-related outcomes and complications were compared between the PPF group (18 flaps in 15 patients) and the FF group (20 flaps in 18 patients). These included complete and partial flap necrosis, venous congestion, delayed osteomyelitis, and the coverage failure rate, defined as the need for secondary flaps due to flap necrosis. RESULTS: The coverage failure rate was 22% in the PPF group and 5% in the FF group, with complete necrosis observed in 11% of the PPF group and 5% of the FF group, and partial necrosis in 39% of the PPF group and 10% of the FF group, indicating no significant difference between the two groups. However, venous congestion was significantly higher in 72% of the PPF group compared to 10% of the FF group. Four PPFs and one FF required FF reconstruction due to implant/fracture exposure from necrosis. Additionally, four PPFs developed delayed osteomyelitis post-healing, requiring reconstruction using free vascularized bone graft in three out of four cases. CONCLUSIONS: Flap necrosis in traumatic lower-leg defects can lead to reconstructive failure, exposing implants or fractures and potentially causing catastrophic outcomes like osteomyelitis, jeopardizing limb salvage. Surgeons should be cautious about deeming PPFs as straightforward and microsurgery-free procedures, given the increased complication rates compared to FFs in traumatic reconstruction. DATA ACCESS STATEMENT: The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

Minimizing Nipple-Areolar Complex Complications in Prepectoral Breast Reconstruction After Nipple-Sparing Mastectomy.

PURPOSE: Nipple-areolar complex (NAC) viability remains a significant concern following prepectoral tissue expander (TE) reconstruction after nipple-sparing mastectomy (NSM). This study assesses the impact of intraoperative TE fill on NAC necrosis and identifies strategies for mitigating this risk. METHODS: A chart review of all consecutive, prepectoral TEs placed immediately after NSM was performed between March 2017 and December 2022 at a single center. Demographics, mastectomy weight, intraoperative TE fill, and complications were extracted for all patients. Partial NAC necrosis was defined as any thickness of skin loss including part of the NAC, whereas total NAC necrosis was defined as full-thickness skin loss involving the entirety of the NAC. P < 0.05 was considered statistically significant. RESULTS: Forty-six patients (83 breasts) with an average follow-up of 22 months were included. Women were on average 46 years old, nonsmoker (98%), and nondiabetic (100%) and had a body mass index of 23 kg/m2. All reconstructions were performed immediately following prophylactic mastectomies in 49% and therapeutic mastectomies in 51% of cases. Three breasts (4%) were radiated, and 15 patients (33%) received chemotherapy. Mean mastectomy weight was 346 ± 274 g, median intraoperative TE fill was 150 ± 225 mL, and median final TE fill was 350 ± 170 mL. Partial NAC necrosis occurred in 7 breasts (8%), and there were zero instances of complete NAC necrosis. On univariate analysis, partial NAC necrosis was not associated with any patient demographic or operative characteristics, including intraoperative TE fill. In multivariable models controlling for age, body mass index, mastectomy weight, prior breast surgery, and intraoperative TE fill, partial NAC necrosis was associated with lower body mass index (odds ratio, 0.53; confidence interval [CI], 0.29-0.98; P < 0.05) and higher mastectomy weight (odds ratio, 1.1; CI, 1.01-1.20; P < 0.05). Prior breast surgery approached significance, as those breasts had a 19.4 times higher odds of partial NAC necrosis (95% CI, 0.88-427.6; P = 0.06). CONCLUSIONS: Nipple-areolar complex necrosis following prepectoral TE reconstruction is a rare but serious complication. In this study of 83 breasts, 7 (8%) developed partial NAC necrosis, and all but one were able to be salvaged.

Impact of endoprosthesis type on inflammatory response in patients undergoing endoscopic drainage of pancreatic fluid collections.

OBJECTIVE: To study the impact of endoprosthesis type on inflammatory response in patients undergoing endoscopic ultrasound (EUS)-guided drainage of pancreatic fluid collections (PFC). METHODS: Patients undergoing EUS-guided PFC drainage and treated using lumen-apposing metal stents (LAMS) or plastic endoprostheses constituted the study cohort. The primary outcome was the presence of systemic inflammatory response syndrome (SIRS) after index intervention. Secondary outcomes were persistent organ failure, new onset organ failure, duration of hospitalization, and treatment success. RESULTS: In all, 303 patients were treated using LAMS (n = 247) or plastic stents (n = 56). At 48 h postintervention, the presence of SIRS (25.0 vs. 14.2%, P = 0.047), new onset SIRS (10.0 vs. 1.8%, P = 0.017), and new organ failure (5.4 vs. 0.4%, P = 0.003) were significantly higher in the plastic stent cohort compared to LAMS. On multivariable logistic regression analysis, the use of plastic stents (odds ratio [OR] 2.7, 95% confidence interval [CI] 1.2-6.0, P = 0.014), patients receiving high-acuity care (OR 5.1, 95% CI 2.5-10.4, P < 0.001) and the presence of ≥33% of necrosis (OR 4.5, 95% CI 2.0-10.0, P < 0.001) were significantly associated with the presence of SIRS or new organ failure. While there was no significant difference in treatment success (96.4 vs. 95.5%, P = 0.77), duration of hospitalization was significantly longer for the plastic stent cohort (mean [standard deviation] 12.5 [17.8] vs. 7.9 [10.1] days, P = 0.009). CONCLUSIONS: Use of plastic stents as compared to LAMS was associated with a higher proportion of SIRS and new organ failure that prolonged hospital stay. Therefore, placement of LAMS is recommended in sick patients and those with ≥33% necrosis to minimize inflammatory response.

Chondroblastomas in Children and Young Adults: Revision of 55 Cases.

BACKGROUND: Chondroblastomas are uncommon primary bone tumors localized in long bone epiphyses in children and young adults. The risk of metastasis is rare, but they have a high capacity for local recurrence. Surgical curettage with bone grafting or bone substitute is the preferred treatment. METHODS: We performed an observational retrospective study of chondroblastomas treated in 2 hospitals in Barcelona from 1988 to 2018. We reviewed the location of the tumor, clinical presentation, imaging, histopathology, initial treatment, and cases of recurrence with a review of their treatment. We assessed the correlation between recurrence and index surgery, anatomic location, and certain histopathologic findings (presence of mitotic figures, necrosis, and positivity for protein S-100). RESULTS: The series included 55 patients treated from 1988 to 2018, with ages ranging from 6 to 26, and a mean follow-up of 6.1 years (±3.7). The most common location was the distal femur metaphyseal/epiphyseal region. The most frequent clinical presentation was pain in the affected. Forty-five cases (81.8%) were treated with curettage of the tumor, and 4 cases (7.3%) with a wide resection. Forty-two cases (85.7%) received bone substitutes after curettage or resection. We found 5 cases of recurrence (9.1% recurrence rate); however, we could not find a statistically significant correlation between index surgery and recurrence ( P =0.24), anatomic location and recurrence ( P =0.49), or recurrence and histopathologic findings (mitotic figures, P =0.49; necrosis, P =0.60; positivity for protein S-100, P =0.52). In all the cases the treatment for the local recurrence was surgical, with a final healing rate of 100%. CONCLUSIONS: Chondroblastomas should be considered in children and adolescents when presenting with pain and an image suggestive of a tumoral lesion on plain x-ray, most frequently in epiphyses of long bones.Surgical treatment is preferred, obtaining good results after curettage and bone substitute. Chondroblastomas are tumors with a high capacity for recurrence, therefore an adequate surgical technique and surgeon experience are paramount to achieve good outcomes. LEVEL OF EVIDENCE: Level IV (case series). Therapeutic studies-investigating results or treatment.

Clinical effectiveness of postoperative prostaglandin E1 administration in reducing flap necrosis following microsurgical reconstruction.

BACKGROUND: Extensive experimental evidence has suggested the potential efficacy of prostaglandin E1 (PGE1) in enhancing flap survival, leading to its widespread empirical use following free flap operation. However, the translation of these experimental findings into clinical benefits remains uncertain. This study aimed to assess the clinical effectiveness of postoperative PGE1 administration on the outcomes of microsurgical reconstruction. METHODS: A retrospective review was conducted for patients who underwent free flap-based reconstruction between September 2020 and November 2022, dividing into two cohorts. For all consecutive cases conducted during the formal half, PGE1 was administered for postoperative 7 days (PGE1 cohort), and for those during the latter, PGE1 was not given (non-PGE1 cohort). The profiles of perfusion-related complications (PRC) were compared between the two cohorts. Further analyses after propensity-score matching were performed. RESULTS: In total, 274 cases were analyzed, consisting of 142 in PGE1 and 132 in non-PGE1 cohort. Baseline characteristics were similar between the two cohorts, except for higher rates of comorbidities and chronic wound-related defects in the PGE1 cohort. Overall PRC developed in 37 cases (13.5%), including 6 (2.1%) total loss and 38 (10.2%) partial necrosis. Compared to the control, the PGE1 cohort exhibited significantly lower rates of overall PRC and partial flap necrosis. This difference remained significant on multivariable analyses. The rate of total flap loss did not differ between the cohorts. Consistent associations were observed in the propensity-score matching analysis. CONCLUSION: Postoperative administration of PGE1 appears to be associated with reduced risks for the development of partial flap necrosis.

Nipple-areola-complex preservation and obesity-Successful in stages.

BACKGROUND: The superiority of nipple-sparing mastectomy (NSM) on breast aesthetics and patient-reported outcomes has previously been demonstrated. Despite 42.4% of adults in the United States being considered obese, obesity has been considered a contraindication to NSM due to concerns for nipple areolar complex (NAC) malposition or ischemic complications. This report investigates the feasibility and safety of a staged surgical approach to NSM with immediate microsurgical breast reconstruction in the high-risk obese population. METHODS: Only patients with a body mass index (BMI) of >30 kg/m2 who underwent bilateral mastopexy or breast reduction for correction of ptosis or macromastia (stage 1), respectively, followed by bilateral prophylactic NSM with immediate microsurgical breast reconstruction with free abdominal flaps (stage 2) were included in the analysis. Patient demographics and surgical outcomes were analyzed. RESULTS: Fifteen patients with high-risk genetic mutations for breast cancer with a mean age and BMI of 41.3 years and 35.0 kg/m2 , respectively, underwent bilateral staged NSM with immediate microsurgical breast reconstruction (30 breast reconstructions). At a mean follow-up of 15.7 months, complications were encountered following stage 2 only and included mastectomy skin necrosis (5 breasts [16.7%]), NAC necrosis (2 breasts [6.7%]), and abdominal seroma (1 patient [6.7%]) all of which were considered minor and neither required surgical intervention nor admission. CONCLUSIONS: Implementation of a staged approach permits NAC preservation in obese patients who present for prophylactic mastectomy and immediate microsurgical reconstruction.

Supra-arcuate free fascial MS-TRAM, a modified technique to reduce donor site morbidity in obese population-comparative study.

BACKGROUND: Abdomen-based free flaps represent the gold standard option in the armamentarium of breast reconstruction. The natural evolution to more preservation with less invasive forms of these flaps has been driven by both patient and surgeon satisfaction. Nevertheless, obese patients are challenging due to the increased risk of compromised flap perfusion and donor site morbidity. This challenge is compounded by the prevalence of obesity worldwide, resulting in more free abdominal flaps being performed for breast reconstruction in obese patients. The authors present the outcomes of a modified supra-arcuate fascial muscle-sparing transverse rectus abdominus myocutaneous (FMS-TRAM) technique compared to standard muscle-sparing transverse rectus abdominus myocutaneous (MS-TRAM) technique to reduce the donor site morbidity while providing a well-vascularized large volume of autologous tissue. METHODS: A retrospective comparative data analysis was conducted at two centers: Cairo University Hospitals, Egypt, and University Hospitals Birmingham, United Kingdom. Standard MS-TRAM was performed in 65 patients between 2008 and 2011 (Group 1) versus 275 patients between 2011 and 2020 (Group 2) who underwent FMS-TRAM. The modified technique involved limiting the fascial incision to above or at the level of the arcuate line to preserve the integrity of the anterior rectus sheath caudally. All patients included were of the obese population (BMI≥30 kg/m2 ) and underwent unilateral post-mastectomy reconstruction. Patient demographics, comorbidities, operative details, and outcomes focusing on donor site morbidity and flap complications were recorded and compared between the two groups. RESULTS: The median age and BMI for Group 1 were 43 and 32, respectively. While for Group 2, they were 47 and 33, respectively. Flap weight ranged from 560 to 1470 g (Mean 705) for Group 1, while Group 2 ranged from 510 to 1560 (mean 715). The majority (280/340 [82%]) of the patients in both groups received radiotherapy. 7.7% of Group 1 were smokers, while in Group 2 it was 4.7%. The percentage of delayed versus immediate reconstruction in Group 1 was 60%/40%, while in Group 2, it was 43%/56%. The incidence of fat necrosis, partial necrosis, and total necrosis was 7.6%.1.5%, and 3%, respectively, for Group 1 and 8%, 1.4%, and 2.6%, respectively, for Group 2. The two-tailed p-value demonstrated a significant statistical difference (p < 0.00001) in donor site morbidity between both groups, with more bulge 20% (13/65) and hernia 1.5% (2/65) occurrence in Group 1 versus 1.9% (5/275) and 0.7% (2/275) in Group 2 respectively, over a follow-up period ranging from 24 to 60 months (mean 32). CONCLUSION: FMS-TRAM flaps are safe, robust, and reliable with less donor site morbidity while maintaining optimal flap perfusion for large volume flaps in obese patients with excellent, durable outcomes. It should be considered a valuable tool in the reconstructive armamentarium of breast reconstruction.

A Machine Learning Approach to Predicting Donor Site Complications Following DIEP Flap Harvest.

BACKGROUND: The additional donor site incisions in autologous breast reconstruction can predispose to abdominal complications. The purpose of this study is to delineate predictors of donor site morbidity following deep inferior epigastric perforator (DIEP) flap harvest and use those predictors to develop a machine learning model that can identify high-risk patients. METHODS: This is a retrospective study of women who underwent DIEP flap reconstruction from 2011 to 2020. Donor site complications included abdominal wound dehiscence, necrosis, infection, seroma, hematoma, and hernia within 90 days postoperatively. Multivariate regression analysis was used to identify predictors for donor site complications. Variables found significant were used to construct machine learning models to predict donor site complications. RESULTS: Of 258 patients, 39 patients (15%) developed abdominal donor site complications, which included 19 cases of dehiscence, 12 cases of partial necrosis, 27 cases of infection, and 6 cases of seroma. On univariate regression analysis, age (p = 0.026), body mass index (p = 0.003), mean flap weight (p = 0.006), and surgery time (p = 0.035) were predictors of donor site complications. On multivariate regression analysis, age (p = 0.025), body mass index (p = 0.010), and surgery duration (p = 0.048) remained significant. Radiographic features of obesity, such as abdominal wall thickness and total fascial diastasis, were not significant predictors of complications (p > 0.05). In our machine learning algorithm, the logistic regression model was the most accurate at predicting donor site complications with the accuracy of 82%, specificity of 0.93, and negative predictive value of 0.87. CONCLUSION: This study demonstrates that body mass index is superior to radiographic features of obesity in predicting donor site complications following DIEP flap harvest. Other predictors include older age and longer surgery duration. Our logistic regression machine learning model has the potential to quantify the risk of donor site complications.

Surgical Management in a Medical Emergency: Disseminated Extensive Tissue Damage Due to Snake Envenomation.

Many snakebite deaths in India may remain unreported as these patients still seek treatment from traditional healers or quacks. Though local and systemic toxicity due to snake envenomation is quite common, the clinical presentation as disseminated extensive tissue damage and ulceration is not seen. We present a lady who presented with extensive skin erosions with tissue necrosis in all four limbs and the trunk. The case was successfully managed with antisnake venom, wound debridement, and split skin grafting. Early antisnake venom halts the progression of tissue damage effects of snake venom. The future treatment of these extensive ulcerations may be the use of drugs that can inhibit the hydrolyzing enzymes of snake venom. The case also stresses the need for excellent wound care after the management of systemic envenomation with antivenom treatment.

Sphenoid Sinus Mucosal Flap after Transsphenoidal Surgery-A Systematic Review.

Background and Objectives: Skull base reconstruction is a crucial step during transsphenoidal surgery. Sphenoid mucosa is a mucosal membrane located in the sphenoid sinus. Preservation and lateral shifting of sphenoid mucosa as sphenoid mucosal flap (SMF) during the transsphenoidal exposure of the sella may be important for later closure. This is the first systematic review to evaluate the utility of sphenoid mucosal flap for sellar reconstruction after transsphenoidal surgery. Materials and Methods: A systematic literature search was performed in January 2023: Cochrane, EMBASE, PubMed, Scopus, and Web of Science. The following keywords and their combinations were used: "sphenoid mucosa", "sphenoid sinus mucosa", "sphenoid mucosal flap", "sphenoid sinus mucosal flap". From a total number of 749 records, 10 articles involving 1671 patients were included in our systematic review. Results: Sphenoid sinus mucosa used to be applied for sellar reconstruction as either a vascularized pedicled flap or as a free flap. Three different types of mucosal flaps, an intersinus septal flap, a superiorly based flap and an inferiorly based flap, were described in the literature. Total SMF covering compared to partial or no SMF covering in sellar floor reconstruction resulted in fewer postoperative CSF leaks (p = 0.008) and a shorter duration of the postoperative lumbar drain (p = 0.003), if applied. Total or partial SMF resulted in fewer local complications (p = 0.012), such as fat graft necrosis, bone graft necrosis, sinusitis or fungal infection, in contrast to no SMF implementation. Conclusions: SMF seems to be an effective technique for skull base reconstruction after transsphenoidal surgery, as it can reduce the usage of avascular grafts such as fat along with the incidence of local complications, such as fat graft necrosis, bone graft necrosis, sinusitis and fungal infection, or it may improve the sinonasal quality of life by maintaining favorable wound healing through vascular flap and promote the normalization of the sphenoid sinus posterior wall. Further clinical studies evaluating sphenoid mucosal flap preservation and application in combination with other techniques, particularly for higher-grade CSF leaks, are required.

Complete tumor necrosis after neoadjuvant chemotherapy defines good responders in patients with Ewing sarcoma.

BACKGROUND: Survival in patients who have Ewing sarcoma is correlated with postchemotherapy response (tumor necrosis). This treatment response has been categorized as the response rate, similar to what has been used in osteosarcoma. There is controversy regarding whether this is appropriate or whether it should be a dichotomy of complete versus incomplete response, given how important a complete response is for in overall survival of patients with Ewing sarcoma. The purpose of this study was to evaluate the impact that the amount of chemotherapy-induced necrosis has on (1) overall survival, (2) local recurrence-free survival, (3) metastasis-free survival, and (4) event-free survival in patients with Ewing sarcoma. METHODS: In total, 427 patients who had Ewing sarcoma or tumors in the Ewing sarcoma family and received treatment with preoperative chemotherapy and surgery at 10 international institutions were included. Multivariate Cox proportional-hazards analyses were used to assess the associations between tumor necrosis and all four outcomes while controlling for clinical factors identified in bivariate analysis, including age, tumor volume, location, surgical margins, metastatic disease at presentation, and preoperative radiotherapy. RESULTS: Patients who had a complete (100%) tumor response to chemotherapy had increased overall survival (hazard ratio [HR], 0.26; 95% CI, 0.14-0.48; p < .01), recurrence-free survival (HR, 0.40; 95% CI, 0.20-0.82; p = .01), metastasis-free survival (HR, 0.27; 95% CI, 0.15-0.46; p ≤ .01), and event-free survival (HR, 0.26; 95% CI, 0.16-0.41; p ≤ .01) compared with patients who had a partial (0%-99%) response. CONCLUSIONS: Complete tumor necrosis should be the index parameter to grade response to treatment as satisfactory in patients with Ewing sarcoma. Any viable tumor in these patients after neoadjuvant treatment should be of oncologic concern. These findings can affect the design of new clinical trials and the risk-stratified application of conventional or novel treatments.

Combined Drainage and Protocolized Necrosectomy Through a Coaxial Lumen-apposing Metal Stent for Pancreatic Walled-off Necrosis: A Prospective Multicenter Trial.

OBJECTIVE: We evaluated a protocolized endoscopic necrosectomy approach with a lumen-apposing metal stent (LAMS) in patients with large symptomatic walled-off pancreatic necrosis (WON) comprising significant necrotic content, with or without infection. SUMMARY BACKGROUND DATA: Randomized trials have shown similar efficacy of endoscopic treatment compared with surgery for infected WON. DESIGN: We conducted a regulatory, prospective, multicenter single-arm clinical trial examining the efficacy and safety of endoscopic ultrasound -guided LAMS with protocolized necrosectomy to treat symptomatic WON ≥6 cm in diameter with >30% solid necrosis. After LAMS placement, protocolized WON assessment was conducted and endoscopic necrosectomy was performed for insufficient WON size reduction and persistent symptoms. Patients with radiographic WON resolution to ≤ 3 cm and/or 60-day LAMS indwell had LAMS removal, then 6-month follow-up. Primary endpoints were probability of radiographic resolution by 60 days and procedure-related serious adverse events. RESULTS: Forty consecutive patients were enrolled September 2018 to March 2020, of whom 27 (67.5%) were inpatients and 19 (47.5%) had clinical evidence of infection at their index procedure. Mean WON size was 15.0 ± 5.6 cm with mean 53.2% ± 16.7% solid necrosis. Radiographic WON resolution was seen in 97.5% (95% CI, 86.8%, 99.9%) by 60 days, without recurrence in 34 patients with 6-month follow-up data. Mean time to radiographic WON resolution was 34.1 ± 16.8 days. Serious adverse events occurred in 3 patients (7.5%), including sepsis, vancomycin-resistant enterococcal bacteremia and shock, and upper gastrointestinal bleeding. There were no procedure-related deaths. CONCLUSIONS: Endoscopic ultrasound-guided drainage with protocolized endoscopic necrosectomy to treat large symptomatic or infected walled-off necrotic pancreatic collections was highly effective and safe. Clinicaltrials.-gov no: NCT03525808.

A Protocolized Management of Walled-Off Necrosis (WON) Reduces Time to WON Resolution and Improves Outcomes.

BACKGROUND AND AIMS: Patients with infected or symptomatic walled-off necrosis (WON) have high morbidity and health care utilization. Despite the recent adoption of nonsurgical treatment approaches, WON management remains nonalgorithmic. We investigated the impact of a protocolized early necrosectomy approach compared with a nonprotocolized, clinician-driven approach on important clinical outcomes. METHODS: Records were reviewed for consecutive patients with WON who underwent a protocolized endoscopic drainage with a lumen-apposing metal stent (cases), and for patients with WON treated with a lumen-apposing metal stent at the same tertiary referral center who were not managed according to the protocol (control subjects). The protocol required repeat cross-sectional imaging within 14 days after lumen-apposing metal stent placement, with regularly scheduled endoscopic necrosectomy if WON diameter reduction was <50%. Control patients were treated according to their clinician's preference without an a priori strategy. Inverse probability of treatment weighting-adjusted analysis was used to evaluate the influence of being in the protocolized group on time to resolution. RESULTS: A total of 24 cases and 47 control subjects were included. There were no significant differences in baseline characteristics. Although numbers of endoscopies and necrosectomies were similar, cases had lower adverse event rates, shorter intensive care unit stay, and required nutritional support for fewer days. On matched multivariate Cox regression, cases had earlier WON resolution (hazard ratio, 5.73; 95% confidence interval, 2.62-12.5). This was confirmed in the inverse probability of treatment weighting-adjusted analysis (hazard ratio, 3.4; 95% confidence interval, 1.92-6.01). CONCLUSIONS: A protocolized strategy resulted in faster WON resolution compared with a discretionary approach without the need for additional therapeutic interventions, and with a better safety profile and decreased health care utilization.