The internal mammary artery perforator flap in pharyngoesophageal, cervical tracheal, and cutaneous neck reconstruction.

The internal mammary artery perforator (IMAP) flap is an evolution of the deltopectoral flap that is harvested based upon a single perforator from the internal mammary artery. Its favorable characteristics include pliability as a fasciocutaneous flap, ease of harvest, and minimal donor site morbidity. In this paper, we report our harvest technique and the versatility of the IMAP flap for pharyngoesophageal, cervical tracheal, and cutaneous neck defects. We seek to highlight the IMAP as a useful regional reconstructive option in both the primary and salvage reconstructive setting. As such, this flap is an important option in the head and neck reconstructive surgeon's armamentarium.

How far are we off? Analyzing the accuracy of surgical margin relocation in the head and neck.

BACKGROUND: Positive surgical margin rates remain high in head and neck cancer surgery. Relocation is challenging given the complex, three-dimensional (3D) anatomy. METHODS: Prospective, multi-institutional study to determine accuracy of head and neck surgeons and pathologists relocating margins on virtual 3D specimen models using written descriptions from pathology reports. Using 3D models of 10 head and neck surgical specimens, each participant relocated 20 mucosal margins (10 perpendicular, 10 shave). RESULTS: A total of 32 participants, 23 surgeons and 9 pathologists, marked 640 margins. Of the 320 marked perpendicular margins, 49.7% were greater than 1 centimeter from the true margin with a mean relocation error of 10.2 mm. Marked shave margins overlapped with the true margin a mean 54% of the time, with no overlap in 44 of 320 (13.8%) shave margins. CONCLUSIONS: Surgical margin relocation is imprecise and challenging even for experienced surgeons and pathologists. New communication technologies are needed.

Comparative Outcomes for Microvascular Free Flap Monitoring Outside the Intensive Care Unit.

OBJECTIVE: There is a trend towards nonintensive care unit (ICU) or specialty ward management of select patients. Here, we examine postoperative outcomes for patients transferred to a general ward following microvascular free flap (FF) reconstruction of the head and neck. STUDY DESIGN: Retrospective quality control study. SETTING: Single tertiary care center. METHODS: Consecutive patients who underwent FF of the head and neck before and after a change in protocol from immediate postoperative monitoring in the ICU ("Pre-protocol") to the general ward setting ("Post-protocol"). Outcomes included overall length of stay (LOS), ICU LOS, FF compromise, and postoperative complications. RESULTS: A total of 150 patients were included, 70 in the pre-protocol group and 80 in the post-protocol group. There were no significant differences in age, sex, comorbidities, tumor stage, or type of FF. Mean LOS decreased from 8.18 to 7.68 days (P = .4), and mean ICU LOS decreased significantly from 5.2 to 1.7 days (P < .01). There were no significant differences in postoperative or airway-related complications (P = .6) or FF failure rate (2.9% vs 2.6%, P > .9). There was a non-significant increase in ancillary consults in the post-protocol group (45% vs 33%, P = .13) and a significant increase in rapid response team calls, a nurse-driven safety net for abnormal vitals or mental status (19% vs 3%, P = .003). CONCLUSION: We show the successful implementation of a protocol shifting care of FF patients from the ICU to a general ward postoperatively, suggesting management on the floor with less frequent flap monitoring is safe and conserves ICU beds. Additional teaching and familiarity with these patients may over time reduce the rapid response calls.

Development of an augmented reality guidance system for head and neck cancer resection.

The use of head-mounted augmented reality (AR) for surgeries has grown rapidly in recent years. AR aids in intraoperative surgical navigation through overlaying three-dimensional (3D) holographic reconstructions of medical data. However, performing AR surgeries on complex areas such as the head and neck region poses challenges in terms of accuracy and speed. This study explores the feasibility of an AR guidance system for resections of positive tumour margins in a cadaveric specimen. The authors present an intraoperative solution that enables surgeons to upload and visualize holographic reconstructions of resected cadaver tissues. The solution involves using a 3D scanner to capture detailed scans of the resected tissue, which are subsequently uploaded into our software. The software converts the scans of resected tissues into specimen holograms that are viewable through a head-mounted AR display. By re-aligning these holograms with cadavers with gestures or voice commands, surgeons can navigate the head and neck tumour site. This workflow can run concurrently with frozen section analysis. On average, the authors achieve an uploading time of 2.98 min, visualization time of 1.05 min, and re-alignment time of 4.39 min, compared to the 20 to 30 min typical for frozen section analysis. The authors achieve a mean re-alignment error of 3.1 mm. The authors' software provides a foundation for new research and product development for using AR to navigate complex 3D anatomy in surgery.

Neighborhood-Level Disadvantage and Delayed Adjuvant Therapy in Head and Neck Cancer.

Importance: For patients with head and neck squamous cell carcinoma (HNSCC), initiation of postoperative radiation therapy (PORT) within 6 weeks of surgery is recommended by the National Comprehensive Cancer Network Guidelines and the Commission on Cancer. Although individual-level measures of socioeconomic status are associated with receipt of timely, guideline-adherent PORT, the role of neighborhood-level disadvantage has not been examined. Objective: To characterize the association of neighborhood-level disadvantage with delays in receiving PORT. Design, Setting, and Participants: This retrospective cohort study included 681 adult patients with HNSCC undergoing curative-intent surgery and PORT from 2018 to 2020 at 4 US academic medical centers. The data were analyzed between June 21, 2023, and March 5, 2024. Main Outcome Measures and Measures: The primary outcome was delay in initiating guideline-adherent PORT (ie, >6 weeks after surgery). Time-to-PORT (TTP) was a secondary outcome. Census block-level Area Deprivation Index (ADI) scores were calculated and reported as national percentiles (0-100); higher scores indicate greater deprivation. The association of ADI scores with PORT delay was assessed using multivariable logistic regression adjusted for demographic, clinical, and institutional characteristics. PORT initiation across ADI score population quartiles was evaluated with cumulative incidence plots and Cox models. Results: Among 681 patients with HNSCC undergoing surgery and PORT (mean [SD] age, 61.5 [11.2] years; 487 [71.5%] men, 194 [29.5%] women) the PORT delay rate was 60.8% (414/681) and median (IQR) TTP was 46 (40-56) days. The median (IQR) ADI score was 62.0 (44.0-83.0). Each 25-point increase in ADI score was associated with a corresponding 32% increase in the adjusted odds ratio (aOR) of PORT delay (aOR, 1.32; 95% CI, 1.07-1.63) on multivariable regression adjusted for institution, age, race and ethnicity, insurance, comorbidity, cancer subsite, stage, postoperative complications, care fragmentation, travel distance, and rurality. Increasing ADI score population quartiles were associated with increasing TTP (hazard ratio of PORT initiation, 0.71; 95% CI, 0.53-0.96; 0.59; 95% CI, 0.44-0.77; and 0.54; 95% CI, 0.41-0.72; for ADI quartiles 2, 3, and 4 vs ADI quartile 1, respectively). Conclusions and Relevance: Increasing neighborhood-level disadvantage was independently associated with a greater likelihood of PORT delay and longer TTP in a dose-dependent manner. These findings indicate a critical need for the development of multilevel strategies to improve the equitable delivery of timely, guideline-adherent PORT.

#OtoTwitter: The Top 75 Twitter Influencers in Otolaryngology and Association With Academic Impact.

OBJECTIVES: Social media has enabled discussion of relevant topics within otolaryngology. With increasing academic discourse occurring on virtual platforms, it is important to examine who is influencing these discussions. This study thus aims to: (1) identify the top Twitter influencers in otolaryngology and (2) assess the relationship between Twitter influence and academic impact. STUDY DESIGN: Cross-sectional analysis. SETTING: Twitter. METHODS: The Right Relevance program was used to identify and rank the top 75 Twitter influencers, excluding organizations, according to the search terms "otolaryngology," "head and neck surgery," "ear nose throat," "rhinology," "head and neck," "laryngology," "facial plastics," and "otology." Demographic data and h-index were collected for each influencer. Correlational analyzes were performed to assess the relationships between Twitter rank and geographic location, sex, subspecialty, and h-index. RESULTS: The majority of the top 75 influencers were otolaryngologists (87%), female (68%), and located in the United States (61%). General otolaryngology (n = 20, 31%) was more well-represented than any individual subspecialty including facial plastics (n = 10, 15%), rhinology (n = 10, 15%), and neurotology (n = 9, 14%). There was a significant relationship between Twitter rank and h-index (Spearman ρ value of -0.32; 95% confidence interval: -0.51 to -0.01; P = .006). Twitter rank was not significantly correlated with subspecialty, sex, or geographic location (P > .05). CONCLUSION: The majority of Twitter influencers within otolaryngology were otolaryngologists, female, and located in the United States. Social media influence is positively associated with academic impact among otolaryngologists.

Effect of preoperative programmed death-1 or programmed death ligand-1 immune check point inhibition on complications after surgery for primary head and neck cancer.

BACKGROUND: There is sparse literature on the effect of preoperative immunotherapy on complications after surgery for primary head and neck squamous cell carcinoma (HNSCC). The objectives are to compare complication rates in patients receiving surgery with and without neoadjuvant immune checkpoint inhibitors (nICI) for primary HNSCC and to evaluate factors associated with increased odds of surgical complications. METHODS: A retrospective review of patients who underwent ablation and free flap reconstruction or transoral robotic surgery (TORS) for primary HNSCC between 2017-2021 was conducted. Complications were compared between patients who underwent surgery with or without nICI before and after propensity score matching. Regression analysis to estimate odds ratios was performed. RESULTS: A total of 463 patients met inclusion criteria. Free flap reconstruction constituted 28.9% of patients and TORS constituted 71.1% of patients. nICI was administered in 83 of 463 (17.9%) patients. There was no statistically significant difference in surgical, medical, or overall complications between patients receiving surgery with or without nICI. In the unmatched cohort, multivariable model identified non-White race, former/current smoking history, free flap surgery, and perineural invasion as factors significantly associated with increased complications. In the matched cohort, multivariable model identified advanced age and free flap surgery as factors significantly associated with increased complications. PLAIN LANGUAGE SUMMARY: It is safe to give immunotherapy before major surgery in patients who have head and neck cancer. Advanced age, non-White race, current/former smoking, free flap surgery, and perineural invasion may be associated with increased the odds of surgical complications.

Virtual 3D Specimen Mapping in Head & Neck Oncologic Surgery.

OBJECTIVES: Virtual 3D specimen mapping of oncologic surgical specimens provides a visual record of the specimen and margin sampling sites which can be utilized in a variety of cancer care settings. Our objective was to perform a retrospective review of head and neck surgical oncology cases where the specimen was mapped post-operatively and to evaluate the utility of these 3D specimen maps amongst the multidisciplinary cancer care team. METHODS: A retrospective review of our 3D specimen model biorepository was performed. Surgical specimens were 3D scanned and then graphically annotated (or "mapped") during routine pathologic processing. The resulting 3D specimen maps were distributed to the multidisciplinary oncologic care team. Final margin status and any use of the 3D specimen maps were recorded. RESULTS: A total of 28 cases were included. Virtual 3D specimen maps were utilized by the cancer care team in 8 cases (29%), including 2 positive margin cases, 2 close margin cases, and 4 indeterminate margin cases. 3D specimen maps were used to visualize positive margin sites for pathologist-surgeon communication as a visual reference during tumor board discussions and to inform radiation treatment planning. CONCLUSION: Post-operative virtual 3D specimen mapping of oncologic specimens creates a permanent visual record of the specimen and the margins sampled and may serve as a beneficial tool for communication amongst the multidisciplinary cancer care team. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:191-197, 2024.

How Often is Cancer Present in Oral Cavity Re-resections After Initial Positive Margins?

OBJECTIVE: To evaluate the rate at which carcinoma is present in the re-resection specimen following initial positive margins during head and neck cancer surgery and its impact on oncologic outcomes. STUDY DESIGN: Retrospective chart review. METHODS: A single institution retrospective chart review of patients that underwent curative-intent surgery for oral cavity cancer was performed. Final pathology reports were reviewed to identify patients with initial positive margins who underwent re-resection during the same operation. Initial positive margin was defined as severe dysplasia, carcinoma in situ (CIS), or carcinoma. Cox proportional hazards and Kaplan-Meier analyses were used to assess for associations with survival outcomes. RESULTS: Among 1873 total patients, 190 patients (10.1%) had initial positive margins and underwent re-resection during the same surgery. Additional carcinoma, CIS, or severe dysplasia was found in 29% of re-resections, and 31% of patients with initial positive margins had final positive margins. Half of the patients with a final positive margin had a positive margin at an anatomic site different than the initial positive margin that was re-resected. The median follow-up was 636 days (range 230-1537). Re-resection with cancer and final positive margin status was associated with worse overall survival (OS; p = 0.044 and p = 0.05, respectively). However, only age, T4 disease, and surgery for recurrent oral cavity cancer were independently associated with OS (p < 0.001, p = 0.005, and p = 0.001, respectively). CONCLUSIONS: Fewer than a third of oral cavity re-resections contain further malignancy, which may suggest that surgeons have difficulty relocating the site of initial positive margin. Final positive margins are often at anatomic sites different than the initial positive margin. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:717-724, 2024.

3D Specimen Scanning and Mapping in Musculoskeletal Oncology: A Feasibility Study.

BACKGROUND: Surgical resection is the primary treatment for bone and soft tissue tumors. Negative margin status is a key factor in prognosis. Given the three-dimensional (3D) anatomic complexity of musculoskeletal tumor specimens, communication of margin results between surgeons and pathologists is challenging. We sought to perform ex vivo 3D scanning of musculoskeletal oncology specimens to enhance communication between surgeons and pathologists. METHODS: Immediately after surgical resection, 3D scanning of the fresh specimen is performed prior to frozen section analysis. During pathologic grossing, whether frozen or permanent, margin sampling sites are annotated on the virtual 3D model using computer-aided design (CAD) software. RESULTS: 3D scanning was performed in seven cases (six soft tissue, one bone), with specimen mapping on six cases. Intraoperative 3D scanning and mapping was performed in one case in which the location of margin sampling was shown virtually in real-time to the operating surgeon to help achieve a negative margin. In six cases, the 3D model was used to communicate final permanent section analysis. Soft tissue, cartilage, and bone (including lytic lesions within bone) showed acceptable resolution. CONCLUSIONS: Virtual 3D scanning and specimen mapping is feasible and may allow for enhanced documentation and communication. This protocol provides useful information for anatomically complex musculoskeletal tumor specimens. Future studies will evaluate the effect of the protocol on positive margin rates, likelihood that a re-resection contains additional malignancy, and exploration of targeted adjuvant radiation protocols using a patient-specific 3D specimen map.

Impact of comorbidities on immediate post-operative complications in oral cavity free flap patients.

PURPOSE: To examine the relationship between comorbidities and the development of immediate post-operative complications in patients undergoing oral cavity composite resection (OCCR) with free flap (FF) reconstruction. MATERIALS AND METHODS: Retrospective analysis was completed on all consecutive OCCRs with FF reconstruction performed at a single quaternary care facility between 1999 and 2020. Comorbidities, immediate post-operative complications, patient demographics, and tumor characteristics were collected. Odds ratios (OR) with 95 % confidence intervals were calculated for associations between comorbidities and immediate post-operative complications. RESULTS: 320 patients who underwent OCCR with FF reconstruction were included. One hundred twenty-one (37.8 %) patients developed a post-operative complication during their initial hospital admission. The most common complications were non-pneumonia cardiopulmonary events (14.1 %), pneumonia (9.4 %), and wound infection (8.4 %). Other complications included flap compromise, bleeding, and fistula. On multivariate analysis, patients without comorbid conditions were less likely to develop a post-operative complication (OR 0.64; 0.41-0.98). Atrial fibrillation (OR 2.94; 1.17-7.39) and cerebrovascular disease (OR 2.28; 1.08-4.84) were associated with increased odds of developing any complications. Furthermore, cerebrovascular disease (OR: 2.33; 1.04-5.39) and peripheral vascular disease (OR: 2.7; 1.2-6.08) were independently associated with pneumonia. CONCLUSION: In this retrospective review of patients undergoing OCCR with FF reconstruction for oral cavity SCC, lack of identifiable comorbidities appeared to be protective for post-operative complications while atrial fibrillation and cerebrovascular disease were associated with increased odds of any complication. Pre-existing vascular disease was also associated with an increased risk of pneumonia.

Oral cavity cancer in young, non-smoking, and non-drinking patients: A contemporary review.

Oral squamous cell carcinoma (OSCC) in non-smoking and non-drinking (NSND) individuals appears to be distinct from the traditional head and neck squamous cell carcinoma (HNSCC). The incidence of this subset is increasing, as are the number of studies examining its characteristics. NSND OSCC individuals tend to be younger (<45 years) compared to traditional HNSCC patients. The proportion of females in the NSND OSCC cohort is also higher. The tongue is the predominantly affected subsite. Studies have revealed several gene mutations and unique epigenomic profiles but no definitive genetic etiology. Transcriptomic analysis has not found any causative viral agents. Other proposed etiologies include chronic dental trauma, microbiome abnormalities, marijuana consumption, and genetic disorders. There are international efforts to determine the relative prognostic outcome of this unique cohort, but no consensus has been reached. Here, we review the incidence, demographics, subsite, possible etiologies, prognosis, and therapy implications of the NSND OSCC cohort.

Resection of a ventral intramedullary spinal cord ependymoma through an anterior cervical approach: illustrative case.

BACKGROUND: Although posterior myelotomy leaves patients with dorsal column deficits, few reports have explored the anterior cervical approach for cervical intramedullary tumors. The authors describe the resection of a cervical intramedullary ependymoma through an anterior approach with a two-level corpectomy and fusion. OBSERVATIONS: A 49-year-old male presented with a C3-5 ventral intramedullary mass with polar cysts. Because of the ventral location of the tumor and the added benefit of avoiding a posterior myelotomy and dorsal column deficits, an anterior C4-5 corpectomy offered a direct route and excellent visualization of the ventrally located tumor. After a C4-5 corpectomy, microsurgical resection, and C3-6 anterior fusion with a fibular allograft filled with autograft, the patient remained neurologically intact. Magnetic resonance imaging (MRI) on postoperative day (POD) 1 confirmed gross-total resection. The patient was extubated on POD 2 and was discharged home on POD 4 with a stable examination. At 9 months, the patient developed mechanical neck pain refractory to conservative treatment and underwent a posterior fusion to address pseudarthrosis. MRI at 15 months showed no evidence of tumor recurrence with the resolution of neck pain. LESSONS: An anterior cervical corpectomy provides a safe corridor to access ventral cervical intramedullary tumors and avoids posterior myelotomy. Although the patient required a three-level fusion, we believe the tradeoff of decreased motion compared to dorsal column deficits is preferred.

Complications following salvage transoral robotic surgery with and without reconstruction: A systematic review of the literature.

BACKGROUND: Transoral robotic surgery (TORS) has been used in the salvage setting for head and neck cancers both with and without reconstruction. The complications of salvage TORS and the effect of reconstruction on complications has not been studied. OBJECTIVE: To study the complications of salvage TORS and examine the effect of reconstruction on complication rates. METHOD: An electronic search of the English- language literature using PubMed, Medline, and the Cochrane database was conducted and a systematic review performed in accordance with PRISMA guidelines (CRD42020181057). RESULTS: A total of 23 studies including 533 patients have been published on salvage TORS.The average patient age was 61.2 years.Prior treatment was described for 420 patients.205 (48.8%) underwent prior definitive radiotherapy (RT).160 (38.1%) underwent definitive chemoradiotherapy (CRT).Only 55 (13.1%) had prior surgery.Overall, there were 158 complications with a pooled rate of 33.6% (95%CI: 25.4-42.3%).77 were major complications requiring surgical intervention with a pooled rate of 18.9% (95% CI: 14.8-23.3%).The number of patients undergoing reconstruction among salvage cases in the literature is 59 (9.19%), with 24 local flaps and 25 microvascular free flaps.Reconstruction was associated with lower overall hemorrhage rates but had no impact on major hemorrhage rates. CONCLUSIONS: The pooled incidence rates of major complications, major POH and emergency tracheostomy following salvage TORS are 18.9%, 10.5%, and 4.4%.The rate of death following salvage TORS is 3.6%. Reconstruction was associated with lower overall hemorrhage rate after salvage TORS but had no impact on major postoperative hemorrhage rates.

Trends in Positive Surgical Margins in cT3-T4 Oral Cavity Squamous Cell Carcinoma.

OBJECTIVE: Positive surgical margins in oral cavity squamous cell carcinoma are associated with cost escalation, treatment intensification, and greater risk of recurrence and mortality. The positive margin rate has been decreasing for cT1-T2 oral cavity cancer over the past 2 decades. We aim to evaluate positive margin rates in cT3-T4 oral cavity cancer over time, and determine factors associated with positive margins. STUDY DESIGN: Retrospective analysis of a national database. SETTING: National Cancer Database 2004 to 2018. METHODS: All adult patients diagnosed between 2004 and 2018 who underwent primary curative intent surgery for previously untreated cT3-T4 oral cavity cancer with known margin status were included. Logistic univariable and multivariable regression analyses were performed to identify factors associated with positive margins. RESULTS: Among 16,326 patients with cT3 or cT4 oral cavity cancer, positive margins were documented in 2932 patients (18.1%). Later year of treatment was not significantly associated with positive margins (odds ratio [OR] 0.98, 95% confidence interval [CI] 0.96-1.00). The proportion of patients treated at academic centers increased over time (OR 1.02, 95% CI 1.01-1.03). On multivariable analysis, positive margins were significantly associated with hard palate primary, cT4 tumors, advancing N stage, lymphovascular invasion, poorly differentiated histology, and treatment at nonacademic or low-volume centers. CONCLUSION: Despite increased treatment at academic centers for locally advanced oral cavity cancer, there has been no significant decrease in positive margin rates which remains high at 18.1%. Novel techniques for margin planning and assessment may be required to decrease positive margin rates in locally advanced oral cavity cancer.

Augmented-Reality Surgery to Guide Head and Neck Cancer Re-resection: A Feasibility and Accuracy Study.

BACKGROUND: Given the complex three-dimensional (3D) anatomy of head and neck cancer specimens, head and neck surgeons often have difficulty relocating the site of an initial positive margin to perform re-resection. This cadaveric study aimed to determine the feasibility and accuracy of augmented reality surgery to guide head and neck cancer re-resections. METHODS: This study investigated three cadaveric specimens. The head and neck resection specimen was 3D scanned and exported to the HoloLens augmented reality environment. The surgeon manually aligned the 3D specimen hologram into the resection bed. Accuracy of manual alignment and time intervals throughout the protocol were recorded. RESULTS: The 20 head and neck cancer resections performed in this study included 13 cutaneous and 7 oral cavity resections. The mean relocation error was 4 mm (range, 1-15 mm) with a standard deviation of 3.9 mm. The mean overall protocol time, from the start of 3D scanning to alignment into the resection bed, was 25.3 ± 8.9 min (range, 13.2-43.2 min). Relocation error did not differ significantly when stratified by greatest dimension of the specimen. The mean relocation error of complex oral cavity composite specimens (maxillectomy and mandibulectomy) differed significantly from that of all the other specimen types (10.7 vs 2.8; p < 0.01). CONCLUSIONS: This cadaveric study demonstrated the feasibility and accuracy of augmented reality to guide re-resection of initial positive margins in head and neck cancer surgery.

Variance in 3D anatomic localization of surgical margins based on conventional margin labeling in head and neck squamous cell carcinoma.

OBJECTIVE: In head and neck cancer (HNC), positive margins are strongly predictive of treatment failure. We sought to measure the accuracy of localization of margin sampling sites based on conventional anatomic labels using a digital 3D-model. METHODS: Preoperative CT scans for 9 patients with HNC treated operatively at our institution were imported into a multiplanar radiology software, which was used to render a digital 3D model of each tumor intended to represent the resection specimen. Surgical margin labels recorded during the operative case were collected from pathology records. Margin labels (N = 64) were presented to participating physicians.Participants were asked to mark the anatomic location of each surgical margin using the 3D-model and corresponding radiographic planes for reference.For each individual margin, the 3D coordinates of each participant's marker were used to calculate a mean localization point called the geometric centroid. Mean distance from individual markers to the centroid was compared between participantsand margin types. RESULTS: Amongst 7 surgeons, markers were placed a mean distance of 12.6 mm ([SD] = 7.5) from the centroid.Deep margins were marked with a greater mean distance than mucosal/skin margins (19.6 [24.8] mm vs. 15.3 [14.9] mm, p = 0.034). When asked to relocate a margin following re-resection, surgeons marked a point an average of 20.6 [12.4] mm from their first marker with a range of 3.9- 45.1 mm. CONCLUSIONS: Retrospective localization of conventionally labeled margins is an imprecise process with variability across the care team. Future interventions targeting margin documentation and communication may improve sampling precision.