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Rumer, Kristen K.

https://orcid.org/0000-0003-2713-8811

Mayo Clinic

Mayo Clinic

Citations 9

Beyond fluorescence intensity: a Minimum acquisition and reporting standard and emerging technologies for colorectal indocyanine green fluorescence angiography studies
Chhetri, Parvat Kuwar , Bhan, Anmol, Rumer, Kristen K., Larson, D. W., Kuwar Chhetri, Parvat, Bhan, Anmol, Rumer, Kristen K. , Larson, David W.

Frontiers in Surgery | July 2, 2026 | Volume: 13 | Issue: No issue available | Pages: No page available

10.3389/fsurg.2026.1864848 Get It

Background Intraoperative indocyanine green fluorescence angiography (ICG-FA) is increasingly utilized to assess bowel perfusion during colorectal anastomosis. Although recent multicenter randomized trials have yielded mixed findings, pooled randomized evidence and 2025 SAGES guidance indicate an overall benefit, particularly in left-sided and rectal surgery. However, acquisition protocols, interpretation criteria, and reported endpoints remain heterogeneous. Main message ICG-FA reflects the dynamics of an intravascular dye signal and is affected by injection technique, hemodynamic status, camera geometry, display mode, and platform-specific processing. Visual interpretation shows substantial interobserver variability. Thus, single fluorescence-intensity snapshots are unstable for comparison. In contrast, time-intensity kinetics and spatial heterogeneity measures are more reproducible and physiologically meaningful. Among reported kinetic metrics, the time ratio (TR = T1/2Max/Tmax) is promising. However, current evidence is preliminary and needs multicenter validation. Proposal We propose a practical minimum acquisition and reporting standard for colorectal ICG-FA studies as an expert-opinion framework for future consensus development. This includes consistent reporting of ICG administration, physiological status at assessment, imaging conditions, camera geometry, analysis methodology, measured outcomes, decision impact, and software/version details. We also describe other relevant approaches, such as laser speckle contrast imaging (LSCI), hyperspectral imaging (HSI), and artificial intelligence (AI)-assisted interpretation. Conclusions The key question is no longer only whether ICG-FA should be used, but how its signal should be acquired, quantified, interpreted, and reported. Better standardization should improve comparability, support multicenter validation, and clarify where perfusion imaging adds the greatest clinical value.
Long-Term Outcomes of Botulinum Toxin in the Treatment of Chronic Anal Fissures: A Stepwise Approach to Managing Recurrent and Persistent Cases
Aboelmaaty, Sara , Gupta, Anupama , Keshk, Nouran O., Gomaa, Ibrahim A. , Perry, William, Rumer, Kristen K. , Perry, William , Cheng Ng, Jyi, Zhang, Lindsey M, Perry, William R , Ng, Jyi Cheng , Zhang, Lindsey M.

Diseases of the Colon & Rectum | January 5, 2026 | Volume: 69 | Issue: 4 | Pages: 608-616

10.1097/dcr.0000000000004034 Get It

BACKGROUND: Chronic anal fissures are a painful condition characterized by a tear in the anal mucosa. Botulinum toxin injection is a minimally invasive treatment option, but long-term effectiveness in recurrent or persistent cases remains unclear. OBJECTIVE: This study evaluates the long-term outcomes of botulinum toxin injections for the treatment of chronic anal fissures. DESIGN: This study is a retrospective review. SETTINGS: The study was conducted at a tertiary academic center. PATIENTS: Adults with chronic anal fissures treated with botulinum toxin between 2018 and 2023 were included. MAIN OUTCOME MEASURES: Short- and long-term healing, recurrence, or persistence after botulinum toxin injection. Persistent or recurrent fissure(s) were followed for outcomes after subsequent repeat injections or surgery (lateral internal sphincterotomy or fissurectomy). RESULTS: Among 161 patients, 45.3% (n = 73) experienced short-term healing after botulinum toxin as first-line therapy, but only 26% (n = 42) had sustained healing. Subsequent treatment patterns were similar for recurrent (n = 31) and persistent (n = 88) fissures: 35% versus 31% no further intervention, 55% versus 42% multiple subsequent injections, 10% versus 23% surgery, respectively. Sustained healing was achieved in 63% (n = 10/16) of patients who underwent surgery compared with 37% (n = 14/38) who had repeat botulinum toxin injections ( p = 0.06). Only 49% achieved sustained healing after a single injection, multiple injections, or injection(s) with surgery. Complications included 5 episodes of mild fecal incontinence in the botulinum toxin group and 2 instances of surgical site infection in the surgery group. LIMITATIONS: Limitations include a single-institution, retrospective study design and loss to follow-up. CONCLUSION: Botulinum toxin remains a valuable therapy for chronic anal fissures. Many patients have persistent or recurrent fissures after botulinum toxin injection and undergo additional interventions. Despite multiple interventions, only half of the patients achieved sustained healing, regardless of the treatment pattern. These data do not support the use of botulinum toxin over surgery for the treatment of chronic fissures, are helpful for counseling patients on the safety profile of each, and set expectations regarding the need for multiple interventions. See Video Abstract . RESULTADOS A LARGO PLAZO DEL USO DE TOXINA BOTULÍNICA EN EL TRATAMIENTO DE FISURAS ANALES CRÓNICAS: UN ENFOQUE GRADUAL PARA EL MANEJO DE CASOS RECURRENTES Y PERSISTENTES ANTECEDENTES: Las fisuras anales crónicas son una afección dolorosa caracterizada por un desgarro en la mucosa anal. La inyección de toxina botulínica es una opción de tratamiento mínimamente invasiva, pero su eficacia a largo plazo en casos recurrentes o persistentes sigue sin estar clara. OBJETIVO: Evaluar los resultados a largo plazo de las inyecciones de toxina botulínica para el tratamiento de las fisuras. DISEÑO: Revisión retrospectiva. ENTORNO: Centro académico terciario. PACIENTES: Adultos con fisuras crónicas tratados con toxina botulínica entre 2018 y 2023. PRINCIPALES MEDIDAS DE RESULTADO: Curación a corto y largo plazo, recurrencia o persistencia después de la inyección de toxina botulínica. Se realizó un seguimiento de las fisuras persistentes o recurrentes para evaluar los resultados después de repetidas inyecciones o cirugía (esfinterotomía interna lateral o fisurectomía). RESULTADOS: Entre los 161 pacientes, el 45,3 % (n = 73) experimentó una curación a corto plazo tras la toxina botulínica como terapia de primera línea, pero solo el 26 % (n = 42) tuvo una curación sostenida. Los patrones de tratamiento posteriores fueron similares para las fisuras recurrentes (n = 31) o persistentes (n = 88): 35 % frente a 31 % sin intervención adicional, 55 % frente a 42 % con múltiples inyecciones posteriores, 10 % frente a 23 % con cirugía, respectivamente. Se logró una curación sostenida en el 63 % (n = 10/16) de los pacientes que se sometieron a cirugía, en comparación con el 37 % (n = 14/38) que recibió inyecciones repetidas de toxina botulínica ( p = 0,06). Solo el 49 % logró una curación sostenida después de una sola inyección, múltiples inyecciones o inyecciones con cirugía. Las complicaciones incluyeron 5 episodios de incontinencia fecal leve en el grupo de la toxina botulínica y dos casos de infección en el sitio quirúrgico en el grupo de la cirugía. LIMITACIONES: Estudio retrospectivo de una sola institución y pérdida de seguimiento. CONCLUSIÓN: La toxina botulínica sigue siendo una terapia valiosa para las fisuras anales crónicas. Muchos pacientes presentan fisuras persistentes o recurrentes tras la inyección de toxina botulínica y se someten a intervenciones adicionales. A pesar de las múltiples intervenciones, solo la mitad de los pacientes lograron una curación sostenida, independientemente del patrón de tratamiento. Estos datos no respaldan el uso de la toxina botulínica frente a la cirugía para el tratamiento de las fisuras crónicas, pero son útiles para asesorar a los pacientes sobre el perfil de seguridad de cada una y establecer expectativas con respecto a la necesidad de múltiples intervenciones. ( AI-generated translation )
Combined TaTME with SP Robot for Low Anterior Resection in Rectal Cancer: rSPa TaTME
Keshk, Nouran O., Perez-Pachon, Mauricio E., Gomaa, Ibrahim A. , Aboelmaaty, Sara , Rumer, Kristen K. , Shawki, Sherief , Gomaa, Ibrahim , Keshk, Nouran O., Larson, David W.

Cancers | April 15, 2025 | Volume: 17 | Issue: 8 | Pages: 1328

10.3390/cancers17081328 Get It

Background: Total mesorectal excision (TME) remains the gold standard for the resection of rectal cancer regardless of the modality: open, laparoscopic, or robotic. The transanal TME (TaTME) approach has been utilized to overcome the difficulties encountered with the dissection of tumors in the distal pelvis. Recently, a single-port robotic approach (rSPa) was introduced, where three arms and a camera emanate from a 2.5 cm diameter port. This report presents the first experience in the United States combining those two approaches (rSPa TaTME) in rectal cancer, evaluating its safety and oncologic outcomes. Methods: This is a retrospective review of our prospectively maintained rectal cancer database. Patient demographics, tumor characteristics, neoadjuvant treatment, and oncologic and surgical outcomes were recorded. Results: Between May 2022 and August 2024, ten patients (six females, four males) with a median age at surgery of 53 years (range: 38–85) and a mean BMI of 26 (±5) kg/m2 were included for analysis. The median distance of tumors from the anorectal junction was 3.2 cm (range: 2–5.3 cm). All patients had negative margins, with eight complete TME specimens, one near complete, and one incomplete. The mean number of lymph nodes harvested was 24 (±11). The average operative time was 351 (243–411) min. The average length of stay was four days. The ileostomy was reversed in nine out of ten patients. Six patients experienced complications within 30 days of surgery. There were no local or distal recurrences, with a mean follow-up of 20 months (range: 4–30). Conclusions: rSPa TaTME is a unique and innovative method of combining two minimally advanced approaches for the resection of distal rectal cancers, with acceptable surgical and oncologic outcomes.
Validated Integration of Tumor Deposits in N Staging for Prognostication in Colon Cancer
Sassun, Richard , Sileo, Annaclara , Ng, Jyi Cheng , Violante, Tommaso , Gomaa, Ibrahim A. , Mandrekar, Jay , Rumer, Kristen K. , Gomaa, Ibrahim , Violante, Tommaso , Cheng, Jyi Ng , Sassun, Richard , McKenna, Nicholas P. , Larson, David W.

JAMA Surgery | February 5, 2025 | Volume: 160 | Issue: 4 | Pages: 408

10.1001/jamasurg.2024.6729 Get It

Importance Tumor deposits have prognostic value in colon cancer, but the current American Joint Committee on Cancer (AJCC) staging only considers them if there are no concurrent positive lymph nodes. Objective To devise a staging system for colon cancer by integrating counts of tumor deposits with positive lymph nodes while retaining the current AJCC staging framework. Design, Setting, and Participants This retrospective cohort study examines data from a large-volume, tertiary care center database (January 2010 through March 2023 with follow-up until December 2023) and the population-based National Cancer Database (January 2010 through December 2020 with follow-up until December 2021). Participants were adults (age 18-75 years) with stage III colon adenocarcinoma who underwent chemotherapy, and had a specified positive lymph node count and tumor deposit count were selected. Exposure A real positive lymph nodes count was developed and used to derive Sassun-Mayo N/tumor, lymph node, and metastasis (TNM) stages that were compared with the AJCC N/TNM stages. Main Outcomes and Measures Receiver operating characteristic (ROC) curves and Kaplan-Meier analyses for 3-year overall survival were performed to assess the efficiency of the 2 staging systems. The concordance index was used for validation using the National Cancer Database. Results From a total patient number of 11 162 (institutional) and 848 704 (national), the final patient numbers were 788 and 77 790, respectively. The institutional database patients had a mean (SD) age of 58.5 (11.5) years; there were 433 male patients (54.9%) and 355 female (45.1%). The national database patients had a mean (SD) age of 59.3 (10.6) years; there were 40 315 male patients (51.8%) and 37 475 female (48.2%). ROC curve areas were improved using the Sassun-Mayo stages (3-year death for AJCC TMN, 0.63 [95% CI, 0.57-0.69] vs 0.66 [95% CI, for 0.60-0.72] for Sassun-Mayo TNM). Kaplan-Meier curves revealed visible overlaps among AJCC N stages, which were absent in the Sassun-Mayo N stages. The concordance index in the Sassun-Mayo N/TNM stages was 0.611 and 0.616, respectively, while in the AJCC N/TNM stages, it was 0.598 and 0.606, respectively. Patients upstaged from N1 to N2 (n = 10 307; 13.2%) had a 3-year overall survival rate nearly identical to that of AJCC N2a patients. Additionally, 3001 patients (3.9%) were upstaged from N2a to N2b, indicating that 13 308 patients (17.1%) with stage III colon cancer across cohorts were understaged. Conclusions and Relevance This study found that Sassun-Mayo N/TNM staging provided superior overall survival stratification compared with the current AJCC staging, suggesting that their implementation could improve prognostication in colon cancer.
Neoadjuvant immunotherapy versus adjuvant chemotherapy in anorectal melanoma
Sassun, Richard , Sileo, Annaclara , Ng, Jyi Cheng , Violante, Tommaso , Gomaa, Ibrahim A. , Block, Matthew S. , Perry, William , Rumer, Kristen K. , Larson, David W. , Larson, David W , Violante, Tommaso , Cheng, Jyi Ng , Perry, William R , Sassun, Richard , Sileo, Annaclara , McKenna, Nicholas P.

British Journal of Surgery | November 4, 2024 | Volume: 111 | Issue: 11 | Pages: No page available

10.1093/bjs/znae269 Get It

Reflections on Living With Cancer During Fellowship
Peterson, U.D., Westphal, Ann J., Rumer, Kristen K. , Peterson, Urbee Disha, Westphal, Ann J.

JAMA Internal Medicine | October 21, 2024 | Volume: 185 | Issue: 2 | Pages: 141

10.1001/jamainternmed.2024.5501 Get It

This Inside Story describes the experiences of the authors, who both received cancer diagnoses during their fellowships.
Tofacitinib Exposure Does Not Increase Postoperative Complications Among Patients With Ulcerative Colitis Undergoing Total Colectomy: A Retrospective Case–Control Study
Gomaa, Ibrahim A. , Aboelmaaty, Sara , Bhatt, Himani , Vierkant, Robert A. , Shawki, Sherief , Larson, David W. , Behm, Kevin T. , Rumer, Kristen K. , Gomaa, Ibrahim , Vierkant, Robert A , Larson, David W

Diseases of the Colon & Rectum | August 1, 2024 | Volume: 67 | Issue: 11 | Pages: 1443-1449

10.1097/dcr.0000000000003440 Get It

BACKGROUND: Ulcerative colitis, total colectomy, and tofacitinib have all been associated with an increased risk of venous thromboembolism. OBJECTIVE: To determine whether preoperative tofacitinib exposure increases venous thromboembolism or other postoperative complications among patients with ulcerative colitis undergoing subtotal colectomy, total colectomy, or total proctocolectomy. DESIGN: Retrospective, case-controlled study at a single institution. SETTINGS: A tertiary referral center. PATIENTS: Adult patients with ulcerative colitis undergoing subtotal colectomy, total colectomy, or total proctocolectomy after 2018 who were taking tofacitinib within 30 days of surgery (n = 56) were compared to age- and sex-matched patients with ulcerative colitis undergoing the same surgeries but who were not exposed to tofacitinib (n = 56). MAIN OUTCOME MEASURE: The primary outcome was differences in the incidence of venous thromboembolism within 90 days of surgery based on tofacitinib exposure. Secondary outcomes were 90-day postoperative complications. RESULTS: Groups were well matched for age (non-tofacitinib: mean 35.2 years [SD 12.0], tofacitinib: 35.9 [SD 12.1], p = 0.36) and sex (41% women in each group, p = 1.00). Medical characteristics were similar between groups except for biological medication exposure 30 days before surgery (non-tofacitinib: 66%, tofacitinib: 36%, p = 0.004). Surgical characteristics did not differ between groups. Most patients were discharged on extended venous thromboembolism prophylaxis (non-tofacitinib: 80% and tofacitinib: 77%). Adjusted for biological exposure, there were no statistically significant differences in venous thromboembolism (non-tofacitinib exposed: 14%, tofacitinib exposed: 4%, p = 0.09) or other postoperative outcomes. LIMITATION: Retrospective, single institutional study. CONCLUSIONS: Among patients with ulcerative colitis undergoing total colectomy or proctocolectomy, exposure to tofacitinib was not associated with an increased risk of venous thromboembolism or other postoperative complications. See Video Abstract . LA EXPOSICIÓN A TOFACITINIB NO AUMENTA LAS COMPLICACIONES POSOPERATORIAS ENTRE PACIENTES CON COLITIS ULCEROSA SOMETIDOS A COLECTOMÍA TOTAL: UN ESTUDIO RETROSPECTIVO DE CASOS Y CONTROLES ANTECEDENTES: La colitis ulcerosa, la colectomía total y el tofacitinib han sido asociados con un mayor riesgo de tromboembolismo venoso. OBJETIVO: Determinar si la exposición preoperatoria a tofacitinib aumenta la tromboembolia venosa u otras complicaciones posoperatorias entre pacientes con colitis ulcerosa sometidos a colectomía subtotal, colectomía total o proctocolectomía total. DISEÑO: Estudio retrospectivo de casos y controles en una sola institución. AJUSTES: Un centro de referencia terciario. PACIENTES: Los pacientes adultos con colitis ulcerosa sometidos a colectomía subtotal, colectomía total o proctocolectomía total después del año 2018 que se encontraron consumiendo tofacitinib dentro de los 30 días posteriores a la cirugía (n = 56) fueron comparados con pacientes con colitis ulcerosa de la misma edad y sexo sometidos a las mismas cirugías pero que no estuvieron expuestos a tofacitinib (n = 56). MEDIDA DE RESULTADO PRINCIPAL: El resultado primario fueron las diferencias en las incidencias de tromboembolismo venoso dentro de los 90 días posteriores a la cirugía según la exposición a tofacitinib. Los resultados secundarios fueron las complicaciones posoperatorias a los 90 días. RESULTADOS: Los grupos se encontraban bien emparejados por edad (sin tofacitinib: media 35,2 años [DE 12,0], tofacitinib: 35,9 [DE 12,1], p = 0,36) y sexo (41% mujeres en cada grupo, p = 1,00). Las características médicas fueron similares entre los grupos, excepto por la exposición a medicamentos biológicos 30 días antes de la cirugía (sin tofacitinib: 66 %, tofacitinib: 36 %, p = 0,004). Las características quirúrgicas no difirieron entre los grupos. La mayoría de los pacientes fueron dados de alta con profilaxis extendida para tromboembolismo venoso (sin tofacitinib: 80% y tofacitinib: 77%). Ajustado a la exposición biológica, no hubo diferencias estadísticamente significativas en el tromboembolismo venoso (no expuestos a tofacitinib: 14%, expuestos a tofacitinib: 4%, p = 0,09) u otros resultados posoperatorios. LIMITACIÓN: Estudio institucional único, retrospectivo. CONCLUSIÓN: Entre los pacientes con colitis ulcerosa sometidos a colectomía total o proctocolectomía, la exposición a tofacitinib no se asoció con un mayor riesgo de tromboembolismo venoso u otras complicaciones posoperatorias. (Traducción—Dr Osvaldo Gauto )
Surgical Abdominal Emergencies among Patients with Cerebral Palsy: A Case Report and Review Article
Aboelmaaty, Sara , Gomaa, Ibrahim A. , Rumer, Kristen K. , Perez, Mauricio E.

World Journal of Colorectal Surgery | July 12, 2024 | Volume: 13 | Issue: 2 | Pages: 54-57

10.4103/wjcs.wjcs_11_24 Get It

Abstract Surgical abdominal emergencies among patients with cerebral palsy (CP) are infrequently reported. The most commonly reported reason for urgent and emergent abdominal surgery among patients with CP is intestinal volvulus. Intestinal volvulus leads to obstruction and vascular compromise, potentially resulting in life-threatening ischemia and necrosis. Volvulus typically presents with abdominal pain and decreased bowel function. When patients are nonverbal and have baseline bowel dysfunction, symptoms of volvulus can be difficult to diagnose. Here, we present a case of an adult female patient with CP who presented with ischemic colitis with perforation and underwent emergency total colectomy and end-ileostomy. Her postoperative course was complicated by two episodes of intestinal volvulus that occurred one and three months after the initial operation. At the second presentation, she had global bowel ischemia due to the volvulus, which led to her death. We have reviewed and summarized the current literature regarding abdominal emergencies among patients with CP.
Appendiceal ganglioneuroma incidentally found during resection of recurrent rectal cancer: case report and review of the literature
Perez, Mauricio E. , Horton, Rachel, Rumer, Kristen K. , Perez Pachon, Mauricio E

Journal of Surgical Case Reports | February 17, 2024 | Volume: 2024 | Issue: 2 | Pages: No page available

10.1093/jscr/rjae019 Get It

Abstract Ganglioneuromas (GN) are benign neuroblastic tumors that arise from neural crest cells. Since they present with nonspecific symptoms, diagnosis is often incidental. We are reporting a case of an adult appendiceal GN incidentally found during rectal cancer surgery. A 42-year-old male was diagnosed with recurrent rectal cancer after experiencing urinary difficulties and buttock pain. A multiple-stage pelvic exenteration was carried out after neoadjuvant chemotherapy and chemoradiation. Prophylactic appendectomy was done during the course of surgery, and pathology reported an appendix with GN at the distal tip. GN are often found incidentally and rarely cause appendicitis. Depending on their location and size, they might become symptomatic. While there is some controversy on whether surgery is the treatment of choice for all GN, diagnosis is rarely apparent preoperatively, and all appendiceal masses should be resected.