Wide Surgical Margins Research Articles

Risk Factors of Microscopically Tumor-Free Surgical Margins for Recurrence and Survival of Oral Squamous Cell Carcinoma Patients.

ObjectivesThe concept of adequate surgical margins remains controversial in oral squamous cell carcinoma (OSCC) surgery. This study aimed to identify surgical margin-related indicators that might impact recurrence and survival of OSCC patients.Materials and MethodsHistopathological examination was performed using hematoxylin-eosin-stained surgical margin tissue sections in 235 OSCC patients. Axin2 and Snail expression at the surgical margin was detected by immunohistochemistry. The impact of the Axin2-Snail cascade on tumorigenesis of the immortalized human oral keratinocyte (IHOK) line was investigated in vivo.ResultsThe width and dysplasia of surgical margins were not significantly associated with the outcome of OSCC patients. In a multivariate analysis using variable clinicopathologic factors and with Axin2 and Snail expression as cofactors, higher age (hazard ratio [HR]:1.050; P=0.047), Axin2 (HR:6.883; P=0.014), and Snail abundance (HR:5.663; P=0.009) had independent impacts on worsened overall survival. Similarly, lesion site in retromolar trigone (HR:4.077; P=0.010), upper (HR:4.332; P=0.005) and lower gingiva (HR:3.545; P=0.012), presence of extranodal extension (HR:9.967; P<0.001), perineural invasion (HR:3.627; P=0.024), and Snail abundance (HR:3.587; P<0.001) had independent impacts on worsened recurrence-free survival. Furthermore, Axin2 knockdown induced decreased Snail expression and attenuated tumorigenesis in the IHOK line.ConclusionHistopathological examination of surgical margins may not be reliable to predict OSCC patient outcome. Molecular analysis may provide a more accurate risk assessment of surgical margins in OSCC. In particular, Axin2 and Snail are potential predictive biomarkers for the risk assessment of surgical margins in OSCC.

Ungual Melanoma Disguised by Onychomycosis

Ungual melanoma is known to be frequently misdiagnosed, and the primary misdiagnosis of ungual melanoma includes onychomycosis. We report a very rare case of onychomycosis concealing ungual melanoma in situ. A 52- year-old male patient presented with a yellow to brown thickened left great toenail that had existed for 10 years. In the front view, Hutchinson's sign which refers periungual extension of brown-black pigmentation from melanonychia was also observed on his hyponychium. First, fungal infection of his toenail was confirmed with positive KOH result. Next, a nail biopsy after nail avulsion was done to assess Breslow depth and to determine surgical margin. And ungual melanoma was diagnosed with immunohistochemical stains. Non-amputative wide local excision with 5 mm surgical margin followed by skin grafting was done Unfortunately in three years ungual melanoma in situ has recurred 2 times and then progressed to invasive malignant melanoma, so he was referred to the Department of plastic surgery for further invasive surgical treatment and regularly monitored to check the recurrence. According to a prior retrospective study, 52% of ungual melanomas were clinically misdiagnosed. Thus, proper diagnosis of ungual melanoma is very important for the patients' better prognosis. It would be important for physicians to examine the nail plate as well as the underneath structures for patients with nail disease including onychomycosis.

Outcome and Prognostic Factors in Cats Undergoing Resection of Intestinal Adenocarcinomas: 58 Cases (2008-2020).

The purpose of this multi-institutional retrospective study was to expand the available data pertaining to pre-operative clinical findings, progression-free and overall survival times, and potential prognostic factors for cats undergoing surgery for intestinal adenocarcinomas. Fifty-eight cats treated over a 12-year period were included in the study. Progression-free and overall survival times were estimated using Kaplan-Meier analyses. Potential prognostic variables were evaluated for associations with progression-free and overall survival using univariate Cox proportional hazards regression analyses. Prior to surgery, the intestinal mass was identified using ultrasonography in 89% of cats in which it was applied; however, imaging findings suggestive of intrathoracic metastases were observed in only 9% of cats. Among 22 cats undergoing ultrasound-guided fine needle aspiration cytology, the results agreed with the results of histopathology in only 10 cats. Discordant results were most commonly related to the presence of marked inflammation in cytology samples, which may have obscured the presence of neoplastic cells. Diffuse intestinal small cell lymphoma was identified as a comorbidity in 5 cats. Resection of the tumor with the objective of obtaining wide surgical margins was performed in each cat. On histopathology, 20 tumors were classified as mucinous adenocarcinoma and 28 were adenocarcinoma not otherwise specified. Intestinal transection site margins were complete in 94% of cats; however, complete mural margins were present in only 15% of cats. Local lymph node metastases were identified in 52% of cats and carcinomatosis was diagnosed in 81% of cats. Disease progression was documented in 32 of the 58 cats (55%). Of these 32 cats, 14 (43%) had local recurrence of the primary intestinal tumor. Median progression-free survival was 203 days (95% CI 130–299 days), and median overall survival time was 284 days (95% CI 200–363 days). Mitotic count was inversely associated with progression-free survival (HR 1.04; 95% CI 1.01–1.07, P = 0.005); however, none of the remaining potential prognostic factors, including administration of adjuvant chemotherapy, were significantly associated with progression-free or overall survival. Feline intestinal adenocarcinoma remains an aggressive and highly fatal disease. Large, randomized controlled clinical trials will be needed to improve the survival prospects for affected cats.

Evaluation of histopathological margin and other recurrence parameters in basal cell carcinoma: A retrospective analysis of 8821 lesions

Basal cell carcinoma (BCC) is the most common skin cancer. Removing the lesion with wide surgical margins and obtaining a microscopically intact margin is considered sufficient in the treatment of BCC. However, it may not always be possible to provide wide and intact margins in cosmetically and functionally important areas. Although recurrence rates after BCC excision vary among studies, the recurrence rate at 5 years is considered to be 2%. BCC subtype, perineural invasion, and close margin are important factors in recurrence. The aims of this study are to investigate the other factors associated with recurrence in BCC treatment and reveal the value of the "histopathological surgical margin" which can help in making the decision for re-excision. A statistically significant correlation is observed between the increase in tumour size and recurrence(p<0.05). The recurrence rate after excision with a histopathologic margin of 1mm or less is 19%. This rate is found to be 8% in patients with a histopathological margin greater than 1mm and 3mm or less. Reticular dermis and deeper tissue invasion statistically increase the recurrence rate. Multiple excision and the presence of residual tumour in the re-excision sample also increase the recurrence rate. In conclusion, recurrence in BCC patients is affected by more than one parameter. We highly recommend re-excision in patients with a histopathological margin of 1mm or less. In tumours with histopathological margins between 1mm and 3mm, the decision for re-excision or "wait-and-see" approach should be made according to the characteristics of the tumours and patients.

The Histopathological Growth Pattern of Colorectal Liver Metastases Impacts Local Recurrence Risk and the Adequate Width of the Surgical Margin.

The histopathological growth pattern (HGP) of colorectal liver metastases (CLM) has been associated with prognosis. This study was designed to elucidate if the HGP is associated with local recurrence risk and impacts the adequate width of surgical margin. All consecutive patients resected for CLM in 2018-2019 were considered. HGP was prospectively classified as follows: desmoplastic, pushing, and replacement. Surgical margin was classified as follows: R0 (margin ≥ 1 mm), R1vasc (0-mm margin, tumor detachment from intrahepatic vessels), and R1par (tumor exposure along transection plane). R0 resections were further distinguished in R0min (1-mm margin) and R0wide (> 1-mm margin). A total of 340 resection areas in 136 patients were analyzed (70 R0min, 143 R0wide, 31 R1vasc, 96 R1par). HGP was desmoplastic in 26 cases, pushing in 221, and replacement in 93. Thirty-six local recurrences occurred (11%, median follow-up 21 months): 1 after R0wide, 4 after R0min, 3 after R1vasc, and 28 after R1par resection. In R1par group, local recurrence rate was high independently of HGP (29%). In R1vasc and R0min groups, local recurrence risk was higher in the replacement group (R1vasc: 29% vs. 4% if pushing/desmoplastic; R0min: 11% vs. 4%). In R0wide group, local recurrence risk was low for all HGP ( < 1%). Independent predictors of local recurrence were replacement HGP (odds ratio = 1.654, P = 0.036), and R1par resection (odds ratio = 57.209, P < 0.001 vs. R0). Replacement HGP is associated with an increased risk of local recurrence. In these patients, a wide surgical margin should be pursued, because R1vasc and R0min resections could be insufficient. R1par resection is inadequate, independently of the HGP.

Association of Adjuvant Radiation Therapy With Long-Term Overall and Recurrence-Free Survival After Hepatectomy for Hepatocellular Carcinoma: A Multicenter Propensity-Matched Study

R0 resection with a wide surgical margin is the gold standard for hepatocellular carcinoma (HCC), yet R0 resection with narrow margins and even R1 resection is not uncommon in real-world clinical practice. We sought to use a propensity-matched analysis to characterize the efficacy of adjuvant radiation therapy on long-term oncological survival after hepatectomy for HCC with narrow or positive margins. Using a multi-institutional database, patients with HCC who underwent hepatectomy with negative margins of 0.1 to 1.0 cm or pathologically positive margins were analyzed. Using propensity score matching (PSM) and multivariate Cox-regression analysis, the effect of adjuvant radiation therapy on long-term overall survival (OS) and recurrence-free survival (RFS) was evaluated. Among 683 patients who met inclusion criteria, 82 patients received adjuvant radiation therapy within 10 weeks after surgery. Radiation therapy-related major toxic effects were minimal among patients receiving adjuvant radiation therapy. PSM analysis created 78 matched pairs of patients. In the PSM cohort, median OS and RFS among patients treated with adjuvant radiation therapy were more favorable than individuals who were not treated (72.5 and 37.3 months versus 52.5 and 24.0 months, both P < .05). After adjustment for other confounding factors on multivariate analyses, adjuvant radiation therapy remained independently associated with favorable OS and RFS after hepatectomy with close/positive surgical margins for HCC (hazard ratios, 0.821 and 0.827, respectively). Despite the lack of consensus on the role of adjuvant radiation therapy after HCC resection, this PSM analysis suggested improved OS and RFS with adjuvant radiation therapy after hepatectomy with close/positive surgical margins for HCC. Future randomized controlled trials are needed to further define the survival benefit of adjuvant radiation therapy for patients with HCC.

Clinical features and treatment outcomes of dedifferentiated and grade 3 chondrosarcoma: A multi-institutional study.

Chondrosarcoma is the second most common primary malignant bone tumor. In this multicenter study, we sought to evaluate the disease‐specific survival (DSS) and disease‐free survival (DFS), and prognostic factors in patients with dedifferentiated chondrosarcoma (DDCS) or grade 3 chondrosarcoma (G3CS) in Japan. We retrospectively investigated the treatment outcomes and prognostic factors in 62 patients with DDCS and 19 patients with G3CS at 15 institutions participating in the Japanese Musculoskeletal Oncology Group. We also clarified significant clinicopathological factors for oncological outcomes. In surgery for primary lesions aimed at cure, a histologically negative margin (R0) was obtained in 93% (14/15) of patients with G3CS and 100% (49/49) of patients with DDCS. The 5‐year DSS was 18.5% in patients with DDCS and 41.7% in patients with G3CS (p = 0.13). Local control was obtained in 80% (12/15) and 79.6% (39/49) of patients with G3CS and DDCS in the primary lesion after surgery with a wide surgical margin, respectively. In multivariate analysis, stage and no treatment/palliative treatment for the primary lesion were independent prognostic factors for DSS of DDCS, and age and no treatment/palliative treatment for DSS of G3CS. The 5‐year DFS rate was 22.8% in 26 patients with DDCS who did not receive adjuvant chemotherapy, and 21.4% in 14 patients who received adjuvant chemotherapy. The prognosis of DDCS remains poor, although R0 resection was carried out in most cases. Effective and/or intensive chemotherapeutic regimens or agents should be considered or developed for patients with high‐grade chondrosarcoma, particularly for those with DDCS.

Microvascular Invasion in Hepatocellular Carcinoma: A Review of Its Definition, Clinical Significance, and Comprehensive Management.

Hepatocellular carcinoma (HCC) is one of the most common types of malignancies in the world, and most HCC patients undergoing liver resection relapse within five years. Microvascular invasion (MVI) is an independent factor for both the disease-free survival and overall survival of HCC patients. At present, the definition of MVI is still controversial, and a global consensus on how to evaluate MVI precisely is needed. Moreover, this review summarizes the current knowledge and clinical significance of MVI for HCC patients. In terms of management, antiviral therapy, wide surgical margins, and postoperative transcatheter arterial chemoembolization (TACE) could effectively reduce the incidence of MVI or improve the disease-free survival and overall survival of HCC patients with MVI. However, other perioperative management practices, such as anatomical resection, radiotherapy, targeted therapy and immune therapy, should be clarified in future investigations.

Fibrin glue assisted amniotic membrane graft reconstruction of conjunctival fornix and canthus following excision of conjunctival tumours.

Conjunctival tumors involving non-limbal locations, such as the fornix and canthus, are typically excised using a “non-touch” technique, often with a wide surgical margin. Reconstruction of these large defects can be difficult due to the contour of the ocular surface and are often complicated by shortening of the fornix, symblepharon formation, and restriction of eye movements. In our experience, the use of amniotic membrane grafts combined with the sealant properties of fibrin glue such as Tisseel® has improved our surgical outcomes during the reconstruction phase. We would like to highlight and describe our surgical technique using fibrin glue and squint hooks to aid amniotic membrane graft reconstruction for surgically challenging locations in the fornix and canthus following excision of conjunctival lesions, with excellent surgical outcomes.

Evaluation of the Surgical Margin Threshold for Avoiding Recurrence after Partial Nephrectomy in Patients with Renal Cell Carcinoma.

PurposeAn adequate minimal surgical margin for partial nephrectomy (PN) has not yet been conclusively established. Therefore, we aimed to compare PN recurrence rates according to surgical margin status and to establish an adequate minimal surgical margin.Materials and MethodsWe retrospectively studied patients with clinically localized renal cell carcinoma who underwent PN between 2005 and 2014. Surgical margin width (SMW) was assessed for all surgical tissues and divided into three groups: SMW <1 mm, SMW ≥1 mm, and positive surgical margin (PSM). The data were analyzed using the Kaplan-Meier method with log-rank tests and multivariate Cox regression models.ResultsOf 748 patients (median age, 55 years; interquartile range, 46–64 years; 220 female), 704 (94.2%) and 44 (5.8%) patients had negative and PSMs, respectively. Recurrence-free survival was significantly lower in patients with PSMs (p<0.001) and was not significantly different between SMW ≥1 mm and <1 mm groups (p=0.604). PSM was a significant predictor of recurrence (hazard ratio: 8.03, 95% confidence interval: 2.74–23.56, p<0.001), in contrast to SMW <1 mm (p=0.680).ConclusionA PSM after PN significantly increases the risk of recurrence. We discovered that even a submillimeter safety surgical margin may be enough to prevent recurrence. To maximize normal renal parenchyma preservation and to avoid cancer recurrence in renal parenchymal tumor patients, PN may be a safe treatment, except for those with a PSM in the final pathology.

Dermatofibrosarcoma Protuberans is Possible Without Skin Involvement

Dermatofibrosarcoma protuberans (DFSP) is a painless, slowly growing, rare skin tumor. It is most common in the trunk part of the body. It is frequently seen in the 40s. It is usually a low-grade sarcoma. DFSP, which is a locally benign-aggressive tumor, begins with a small size and may infiltrate the skin, subcutaneous adipose tissues, muscles and bones, and may recur despite extensive excision. It never metastasize without higher grade fibrosarcomatous changes. Although the benefit of chemotherapy and radiotherapy is limited, it can be applied in cases of recurrence or metastasis. We present a case of DFSP without skin lesions in a 46-year-old woman presenting with a slow-growing mass on her back. The mass was removed with a wide surgical margin. We aimed to emphasize that DFSP, which is very rare, can be seen without dermal involvement.

Prediction of surgical margin width using Mohs micrographic surgery for extramammary Paget's disease based on clinicopathological parameters: classification tree analysis of 150 cases.

Extramammary Paget's disease (EMPD) frequently extends beyond clinical borders, causing a high recurrence rate. Mohs micrographic surgery (MMS) has been used for management of EMPD, but its efficiency is compromised by technical limitations inherent in MMS. To identify clinicopathologic parameters of predictive value regarding MMS final margin width (FMW) for EMPD, and provide some preliminary guidance in selecting initial surgical margin width for improved efficiency. This was a retrospective study of 150 consecutive EMPD patients who underwent MMS between 2013 and 2019. Clinicopathological parameters and surgical data were collected to construct a classification tree of FMW. A six-node classification tree with a sensitivity of 86.25% and a specificity of 48.57% was generated. Lesion width, disease duration and inflammation score were used to select subgroups of patients in whom optimal initial margin width may be recommended. Classification tree analysis may help identify important variables to consider when selecting MMS initial surgical margins for EMPD.

Extensor Mechanism-Sparing Technique for Management of Proximal Tibia Sarcoma Resection: A Case Series Study

The proximal tibia is one of the most challenging anatomic sites for resection of large bone tumors, due to the vicinity of the extensor mechanism. Here, we report outcomes of a novel radical resection technique which preserves the extensor apparatus. 8 patients were operated between 2001 and 2011 for large sarcomas with high-grade tibial localization. Six were giant cell tumor of bone histology (GCTB; defined as severe bone destruction and soft tissue extension) and two chrondrosarcoma at surgical grade G1, but with double localization in tibia and femur. Primary bone tumors and recurrences were treated with novel multiplanar resection technique avoiding removal of the tibial tuberosity and the patella tendon insertion, preserving extensor mechanism. In all cases, curettage and borage were not indicated due to extensive lesion size. Radical resection of the lower extremity (2 femurs and 8 tibias) yielded wide margins (R0) and patients were evaluated at 10 years of follow up. The average post operative Musculoskeletal Tumor Society (MSTS) score was 26.87 points (range: 23-29). All patients reached full passive and active extension and the maximum active flexion was 108.75° (range: 90°-120°). At the last follow-up (mean: 121.8 months), all patients and implants survived; no local infection, recurrence, metastasis, or relevant complications occurred. This surgical technique therefore appears to provide a safe treatment option when wide surgical margins are possible, and preserving the integrity of the extensor mechanism may improve the clinical outcome.

Anatomic resection improved the long-term outcome of hepatocellular carcinoma patients with microvascular invasion: A prospective cohort study.

BACKGROUNDThe long-term effect of anatomic resection (AR) is better than that of non-anatomic resection (NAR). At present, there is no study on microvascular invasion (MVI) and liver resection types.AIMTo explore whether AR improves long-term survival in patients with hepatocellular carcinoma (HCC) by removing the peritumoral MVI.METHODSA total of 217 patients diagnosed with HCC were enrolled in the study. The surgical margin was routinely measured. According to the stratification of different tumor diameters, patients were divided into the following groups: ≤ 2 cm group, 2-5 cm group, and > 5 cm group.RESULTSIn the 2-5 cm diameter group, the overall survival (OS) of MVI positive patients was significantly better than that of MVI negative patients (P = 0.031). For the MVI positive patients, there was a statistically significant difference between AR and NAR (P = 0.027). AR leads to a wider surgical margin than NAR (2.0 ± 2.3 cm vs 0.7 ± 0.5 cm, P < 0.001). In the groups with tumor diameters < 2 cm, both AR and NAR can obtain a wide surgical margin, and the surgical margins of AR are wider than that of NAR (3.5 ± 5.8 cm vs 1.6 ± 0.5 cm, P = 0.048). In the groups with tumor diameters > 5 cm, both AR and NAR fail to obtain wide surgical margin (0.6 ± 1.0 cm vs 0.7 ± 0.4 cm, P = 0.491). CONCLUSIONFor patients with a tumor diameter of 2-5 cm, AR can achieve the removal of peritumoral MVI by obtaining a wide incision margin, reduce postoperative recurrence, and improve prognosis.

Melanoma trials that defined surgical management: Overview of trials that established NCCN margin guidelines.

Since the observation that clearance of all visible and microscopic tumors from cutaneous melanoma is critical to prevent a recurrence, wide surgical margins have been central to surgical dogma. In the last several decades, more conservative margin widths have been vigorously studied by surgical investigators to lessen wound complications, the need for reconstruction, and healthcare costs. This review summarizes surgeon-led clinical trials that define current guidelines and highlights the challenges to initiate and perform trials today.

Feasibility Investigation of Fluorescence Method in Uniport Thoracoscopic Anatomical Segmentectomy for Identifying the Intersegmental Boundary Line

背景与目的肺段切除术逐渐成为影像学上表现为早期肺癌的肺部小结节的标准手术方式之一。本研究通过对比单孔胸腔镜下荧光法与改良膨胀萎陷法在界定段间交界线的围手术期结果，评估荧光法应用于肺段切除术的有效性和可行性。方法回顾性分析2018年2月-2020年8月期间在南京胸科医院胸外科接受单孔胸腔镜肺段切除术的连续198例患者的围手术期数据。在三维智能交互式定性和定量分析（intelligent/interactive qualitative and quantitative analysis-three dimensional, IQQA-3D）图像分析系统的指导下，精确识别和解剖离断靶段结构，继而通过荧光法或改良膨胀萎陷法确认段间交界线。评价两种方法的临床疗效和术后并发症。结果荧光法组有98%的患者呈现出清晰的段间交界线，甚至部分患者使用了较低剂量的吲哚菁绿（indocyanine green, ICG）。相比改良膨胀萎陷法，荧光法的段间交界线的清晰呈现时间[(23.59±4.47) s vs (1, 026.80±318.34) s, P < 0.01]和手术时间[(89.3±31.6) min vs (112.9±33.3) min, P < 0.01]明显缩短。改良膨胀萎陷法术后长时间漏气的发生率高于荧光法组（8.0% vs 26.5%, P=0.025）。两组的术中失血量、术后胸管持续引流时间、术后住院时间、手术切缘宽度及其他术后并发症均无明显差异（P均 > 0.05）。结论荧光法可以高度准确地识别段间交界线，使得解剖性肺段切除术更加简单、更加快速，因此荧光法有可能成为一种可行且有效的技术，以提高单孔胸腔镜肺段切除术的质量。

Anatomical vs nonanatomical liver resection for solitary hepatocellular carcinoma: A systematic review and meta-analysis.

BACKGROUNDThe long-term survival of patients with solitary hepatocellular carcinoma (HCC) following anatomical resection (AR) vs non-anatomical resection (NAR) is still controversial. It is necessary to investigate which approach is better for patients with solitary HCC.AIMTo compare perioperative and long-term survival outcomes of AR and NAR for solitary HCC.METHODSWe performed a comprehensive literature search of PubMed, Medline (Ovid), Embase (Ovid), and Cochrane Library. Participants of any age and sex, who underwent liver resection, were considered following the following criteria: (1) Studies reporting AR vs NAR liver resection; (2) Studies focused on primary HCC with a solitary tumor; (3) Studies reporting the long-term survival outcomes (> 5 years); and (4) Studies including patients without history of preoperative treatment. The main results were overall survival (OS) and disease-free survival (DFS). Perioperative outcomes were also compared.RESULTSA total of 14 studies, published between 2001 and 2020, were included in our meta-analysis, including 9444 patients who were mainly from China, Japan, and Korea. AR was performed on 4260 (44.8%) patients. The synthetic results showed that the 5-year OS [odds ratio (OR): 1.19; P < 0.001] and DFS (OR: 1.26; P < 0.001) were significantly better in the AR group than in the NAR group. AR was associated with longer operating time [mean difference (MD): 47.08; P < 0.001], more blood loss (MD: 169.29; P = 0.001), and wider surgical margin (MD = 1.35; P = 0.04) compared to NAR. There was no obvious difference in blood transfusion ratio (OR: 1.16; P = 0.65) or postoperative complications (OR: 1.24, P = 0.18).CONCLUSIONAR is superior to NAR in terms of long-term outcomes. Thus, AR can be recommended as a reasonable surgical option in patients with solitary HCC.

Neither Surgical Margin Status nor Somatic Mutation Predicts Local Recurrence After R0-intent Resection for Colorectal Liver Metastases

BackgroundWe evaluated the associations of surgical margin status and somatic mutations with the incidence of local recurrence (LR) and oncologic outcomes in patients undergoing R0-intent (microscopically negative margin) resection of colorectal liver metastases (CLM). MethodsPatients with CLM who underwent initial R0-intent resection and analysis of tumor tissue using next-generation sequencing during 2001–2018 were analyzed. Recurrences were classified as LR (at the resection margin), other intrahepatic recurrence, or extrahepatic recurrence. Predictors and survival effect of LR were evaluated using univariate and multivariate analysis. ResultsOf 552 patients analyzed, 415 (75%) had R0 resection (margin width ≥ 1.0 mm), and 38 (7%) had LR. LR incidence was not affected by surgical margin width. RAS/TP53 co-mutation was associated with increased risk of intrahepatic recurrence (67% vs. 49%; p < 0.001) and overall recurrence (p < 0.001). However, incidence of LR did not differ significantly by RAS/TP53, BRAF, SMAD4, or FBXW7 mutation. Extrahepatic disease (hazard ratio [HR], 1.47; p = 0.034), > 8 cycles of preoperative chemotherapy (HR, 1.98; p = 0.033), tumor viability ≥ 50% (HR, 1.55; p = 0.007), RAS/TP53 co-mutation (HR, 1.69; p = 0.001), and SMAD4 mutation (HR, 2.44; p < 0.001) were independently associated with poor overall survival, but surgical margin status was not. ConclusionsAlthough somatic mutations were associated with overall recurrence, neither surgical margin width nor somatic mutations affected LR risk after R0-intent hepatectomy for CLM. LR and prognosis were likely driven by individual tumor biology rather than surgical margins.

Risk of Recurrence and Patterns of Failure in Estrogen Receptor-Negative Ductal Carcinoma In Situ Patients

Ductal carcinoma in situ (DCIS) constitutes 15%-25% of newly diagnosed breast cancers. Similar to invasive breast cancer, DCIS tumors vary in terms of immunohistochemistry markers and pathological variables. For invasive carcinoma, treatment options and prognosis depend on these factors, including the expression of estrogen receptors (ER). ER negative (ER-) invasive breast cancers are known to be more aggressive. Treatment guidelines and prognosis for DCIS, however, are less well defined. Compared to ER+ DCIS, ER- DCIS is a far less common diagnosis, with 75% of DCIS expressing ER receptors. Data specific for ER- DCIS patients are thus lacking. The objective of this study was to investigate recurrence rates and patterns of failure of ER- DCIS in a single institution, and compare these statistics to the historic predominantly ER+ data in attempt to enhance risk stratification methods for DCIS patients in the future.We performed a retrospective review of medical records of DCIS patients diagnosed between 2004 and 2018, identifying 138 patients with ER negative tumors. 22 patients were lost to follow up immediately after diagnosis and were excluded from further analysis. Median follow up time for the remaining 116 patients was 46.5 months. Data on recurrence were collected. Statistical analysis included descriptive statistics, chi-square test, T-test for independent samples, and logistic regression.11 (9.5%) patients were found to have breast cancer recurrence. Median time to recurrence was 37 months. 8 (72.7%) patients developed a non-invasive recurrence (DCIS), with the remaining patients diagnosed with invasive ductal carcinoma (IDC). The recurrence was ipsilateral in 7 (63.6%) patients, and contralateral in the remaining 4 (36.4%). All DCIS recurrences were ER- as opposed to IDC recurrences, all of which expressed ER receptors. Patients who developed a recurrence underwent a lumpectomy 90.9% of the time for their initial resection, compared with 56.2% of patients with non-recurrent DCIS. We next evaluated the use of adjuvant RT, RT dose, tumor grade, size, presence of necrosis, and width of surgical margins as predictors of recurrence. Neither rates of RT administration, nor the RT dose were significantly different between the patients who developed recurrent disease versus those who did not. There was a trend toward higher recurrence for patients with high grade DCIS (grade 3) and presence of necrosis. Other factors (tumor size, presence of necrosis, and width of excision margins) did not predict for recurrence risk in our sample.Contrary to expectations, ER- DCIS recurrence rates were similar to previously reported DCIS recurrence rates. This is in contrast to the well described findings for ER- invasive carcinomas. Future prospective studies are needed to further evaluate the outcomes for this patient population.

1330 How Does the Tumour-Free Margin Width After Breast-Conserving Surgery in Patients with Ductal Carcinoma in Situ (DCIS) Impact Local Recurrence Rates?

Abstract Introduction In the UK, breast conserving surgery (BCS) has been indicated to completely excise ductal carcinoma in situ(DCIS) to negative margins for around 70% of diagnosed women. The tumour-free radial surgical margin width is an important marker for determining the local recurrence (LR). Setting the margin too wide will result in additional re-excision and too low may result in increased LR rates. This review investigates the different tumour-free margins and its effect on LR. Method A literature review was conducted using the Cochrane library and Pubmed database with key terms. Cohort studies of more than 100 participants with a five-year follow up in women over 18 were included. Results &amp;gt;2mm versus 0mm: LR was significantly reduced in DCIS from one very-low evidence retrospective cohort studies (N = 1,503). &amp;gt;2mm versus 1-2mm: Meaningful reduction in LR with DCIS was found in one very low-quality retrospective cohort study(N = 433). &amp;gt;2mm versus &amp;lt;1mm: Clinically meaningful reduction in LR for DCIS was found in very low-quality retrospective study (N = 466). &amp;gt;2mm versus 1-2mm: Meaningful reduction in LR with DCIS was found in one very low-quality retrospective cohort study(N = 433). Conclusions LR rates were reduced by further increasing the negative margin width in DCIS but only low-quality evidence was available to define these margins. This is an area for further research to enhance patient care and prevent increased LR.