Safe Resection Margin Research Articles

Tumor regression and safe distance of distal margin after neoadjuvant therapy for rectal cancer.

Neoadjuvant therapy has been widely employed in the treatment of rectal cancer, demonstrating its utility in reducing tumor volume, downstaging tumors, and improving patient prognosis. It has become the standard preoperative treatment modality for locally advanced rectal cancer. However, the efficacy of neoadjuvant therapy varies significantly among patients, with notable differences in tumor regression outcomes. In some cases, patients exhibit substantial tumor regression, even achieving pathological complete response. The assessment of tumor regression outcomes holds crucial significance for determining surgical approaches and establishing safe margins. Nonetheless, current research on tumor regression patterns remains limited, and there is considerable controversy surrounding the determination of a safe margin after neoadjuvant therapy. In light of these factors, this study aims to summarize the primary patterns of tumor regression observed following neoadjuvant therapy for rectal cancer, categorizing them into three types: tumor shrinkage, tumor fragmentation, and mucinous lake formation. Furthermore, a comparison will be made between gross and microscopic tumor regression, highlighting the asynchronous nature of regression in the two contexts. Additionally, this study will analyze the safety of non-surgical treatment in patients who achieve complete clinical response, elucidating the necessity of surgical intervention. Lastly, the study will investigate the optimal range for safe surgical resection margins and explore the concept of a safe margin distance post-neoadjuvant therapy.

Impact of the Size and Depth of Pulmonary Nodules on the Surgical Approach for Lung Resection in the Treatment of Early-stage Lung Cancer ≤2 cm

Current studies suggest that for early-stage lung cancers with a component of ground-glass opacity measuring ≤2 cm, sublobar resection is suitable if it ensures adequate margins. However, lobectomy may be necessary for some cases to achieve this. The aim of this study was to explore the impact of size and depth on surgical techniques for wedge resection, segmentectomy, and lobectomy in early-stage lung cancer ≤2 cm, and to determine methods for ensuring a safe resection margin during sublobar resections. Clinical data from 385 patients with early-stage lung cancer ≤2 cm, who underwent lung resection in 2022, were subject to a retrospective analysis, covering three types of procedures: wedge resection, segmentectomy and lobectomy. The depth indicator as the OA value, which is the shortest distance from the inner edge of a pulmonary nodule to the opening of the corresponding bronchus, and the AB value, which is the distance from the inner edge of the nodule to the pleura, were measured. For cases undergoing lobectomy and segmentectomy, three-dimensional computed tomography bronchography and angiography (3D-CTBA) was performed to statistically determine the number of subsegments required for segmentectomy. The cutting margin width for wedge resection and segmentectomy was recorded, as well as the specific subsegments and their quantities removed during lung segmentectomy were documented. In wedge resection, segmentectomy, and lobectomy, the sizes of pulmonary nodules were (1.08±0.29) cm, (1.31±0.34) cm and (1.50±0.35) cm, respectively, while the depth of the nodules (OA values) was 6.05 (5.26, 6.85) cm, 4.43 (3.27, 5.43) cm and 3.04 (1.80, 4.18) cm for each procedure, showing a progressive increasing trend (P<0.001). The median resection margin width obtained from segmentectomy was 2.50 (1.50, 3.00) cm, significantly greater than the 1.50 (1.15, 2.00) cm from wedge resection (P<0.001). In wedge resections, cases where AB value >2 cm demonstrated a higher proportion of cases with resection margins less than 2 cm compared to those with margins greater than 2 cm (29.03% vs 12.90%, P=0.019). When utilizing the size of the nodule as the criterion for resection margin, the instances with AB value >2 cm continued to show a higher proportion in the ratio of margin distance to tumor size less than 1 (37.50% vs 17.39%, P=0.009). The median number of subsegments for segmentectomy was three, whereas lobectomy cases requiring segmentectomy involved five subsegments (P<0.001). The selection of the surgical approach for lung resection is influenced by both the size and depth of pulmonary nodules. This study first confirms that larger portions of lung tissue must be removed for nodules that are deeper and larger to achieve a safe margin. A distance of ≤2 cm from the inner edge of the pulmonary nodule to the nearest pleura may be the ideal indication for performing wedge resection.

Endoscopic endonasal combined transoral medial approach to the nasopharynx, parapharyngeal space, and jugular foramen.

This study aimed to validate the feasibility of an endoscopic endonasal combined transoral medial approach for treating lesions in the nasopharynx, parapharyngeal space (PPS), and jugular foramen. Anatomical and imaging information of six patients who underwent surgery via this approach were reviewed and analyzed. The feasibility and advantages of the endoscopic endonasal combined transoral medial approach, which uses an inside-to-outside medial surgical corridor, were identified. Total resection was achieved in 3 cases with benign tumors. Safe resection margins were obtained in 2 cases with recurrent nasopharyngeal carcinoma (NPC). Pathological biopsy of NPC lesion between the Eustachian tube and arterial sheath was achieved. The internal carotid artery (ICA) was accurately located and protected in all cases and no complications occurred. Lesions in the nasopharynx, PPS, and jugular foramen can be directly assessed via this approach. The ICA can be well identified during the surgery.

Resection margins, lymph node harvest and 3 year survival in open and laparoscopic colorectal cancer surgery; a prospective cohort study

IntroductionLaparoscopic colorectal cancer surgery has been gaining popularity in the last decade. However, there are concerns about adequate lymph node dissection and safe resection margins in laparoscopic colorectal cancer surgery. This study was aimed at comparing the lymph node (LN) clearance and surgical resection margins and 3-year survival for open and laparoscopic colorectal cancer surgery.MethodA pre-tested interviewer administered questionnaire was used to assess the adoption of the laparoscopic approach by Sri Lankan surgeons. Data was collected prospectively from patients who underwent open or laparoscopic colorectal cancer surgery at the University Surgical Unit of the National Hospital of Sri Lanka from April 2016 to May 2019. The histopathology records were analysed to determine the longitudinal and circumferential resection margins(CRM) and the number of lymph nodes harvested. The resection margins were classified as positive or negative. The total number of LN examined was evaluated. Presence of local recurrence and liver metastasis was determined by contrast enhanced CT scan during 3-years of follow up. Chi square, T test and z test for proportions were used to compare CRM, LN harvest and survival rates between the groups.ResultsOf the surgeons interviewed only 11 (18.4%) performed laparoscopic colorectal cancer surgery. A total of 137 patients (83 males and 54 females) were studied. Eighty-one procedures were laparoscopic and 56 procedures were open. All patients had clear longitudinal resection margins. Seventy-eight patients in the laparoscopic group (96%) and 51 patients (91%) in the open group had clear CRM (p > 0.05). A total of 2188 LNs (mean 15.9) were resected in all procedures. Six-hundred-eighty-nine lymph nodes were removed during open procedures (mean 12.3, SD 0.4) and 1499 (mean 18.5, SD 0.6) were removed during laparoscopy (p < 0.05). At 3 years follow-up the disease-free survival in the laparoscopic and open colon cancer patients was 27/41 (65.8%) and 16/29 (55.1%) respectively (p = 0.35). Disease free survival in the laparoscopic and open rectal cancer patients was 23/38 (60.5%) and 13/25 (52.0%) respectively (p = 0.40). Four patients were lost during follow-up.Discussion and conclusionCRM was comparable in the two groups. Laparoscopic group had a significantly higher LN harvest. Three-year survival rates were similar in the two groups. Acceptable results can be obtained with laparoscopic colorectal cancer surgery.

Conformal sphincteric resection for ultra-low rectal cancer located below the dentate line: A pilot report.

Sphincter-sparing surgery can be achieved in most cases of low rectal cancer with the development of intersphincteric resection. However, abdominoperineal resection is still inevitable for patients with tumours located below the dentate line. To address this, we have developed a procedure called conformal sphincteric resection (CSR) in which the corresponding part of the subcutaneous portion of the external anal sphincter and the perianal skin on the tumour side is removed to achieve a safe distal resection margin and lateral resection margin while the dentate line and the internal anal sphincter on the tumour-free side are preserved as much as possible, to achieve sphincter preservation without compromising oncological safety and functional acceptability, and to render tumour location no longer a contraindication for sphincter-sparing surgery. This is the first study to describe the concept, indication and surgical procedure of CSR and to report its preliminary surgical, oncological and functional results. This is a retrospective, single-centre, single-arm pilot study conducted at Huashan Hospital, Fudan University. Demographic, clinicopathological, oncological and functional follow-up data were collected from 20 consecutive patients with rectal tumours located below the dentate line who underwent laparoscopic CSR by the same surgical team from June 2018 to March 2022. The mean distance of the tumour's lower edge from the anal verge was 13.1 ± 6.0 mm. The mean distal resection margin was 10.6 ± 4.3 mm. All circumferential resection margins were negative. There were no instances of perioperative mortality. The complication rate was 25% but all were Clavien-Dindo Grade I. Among the 20 cases, 17 were diagnosed with adenocarcinoma, one with squamous cell carcinoma and two with adenoma featuring high-grade intraepithelial neoplasia. Pathological TNM staging revealed two, seven, five, five and one case(s) in Stages 0, I, II, III and IV, respectively. The median follow-up period was 20 months (interquartile range 22 months), with no withdrawals. The overall and disease-free survival rates were both 95%. The mean Wexner incontinence score and low anterior resection syndrome score recorded 18 months following diverting ileostomy closure were 6.3 ± 3.8 and 27.3 ± 3.6, respectively. This study has proposed the CSR procedure for the first time, which is a technically feasible, oncologically safe and functionally acceptable procedure for carefully selected patients with rectal tumours located below the dentate line.

Optimal surgical techniques for curative resection of the rectal cancer

Abstract The aim of rectal cancer surgery is to achieve a curative resection by completely removing the rectum involved with cancer surrounding the mesorectum, obtaining a safe adequate resection margin, and preserving important structures crucial for the patient's quality of life. Optimal dissection along the avascular embryological fusion line and among deep invisible structures is essential. Whereas a minimally invasive surgical approach allows for better visibility of deep pelvic structures compared with the open surgery period, the sequence of dissection and anatomical knowledge about pelvic fascia and relevant nerve structures are crucial for safe pelvic dissection in terms of oncologic and functional outcomes. In this review, we represent practical technical tips based on personal experience and previous studies to achieve the mentioned goals.

Measurement of distal intramural spread and the optimal distal resection by naked eyes after neoadjuvant radiation for rectal cancers

BackgroundThe safe distance between the intraoperative resection line and the visible margin of the distal rectal tumor after preoperative radiotherapy is unclear. We aimed to investigate the furthest tumor intramural spread distance in fresh tissue to determine a safe distal intraoperative resection margin length.MethodsTwenty rectal cancer specimens were collected after preoperative radiotherapy. Tumor intramural spread distances were defined as the distance between the tumor’s visible and microscopic margins. Visible tumor margins in fresh specimens were identified during the operation and were labeled with 5 - 0 sutures under the naked eye at the distal 5, 6, and 7 o’clock directions of visible margins immediately after removal of the tumor. After fixation with formalin, the sutures were injected with nanocarbon particles. Longitudinal tissues were collected along three labels and stained with hematoxylin and eosin. The spread distance after formalin fixation was measured between the furthest intramural spread of tumor cells and the nanocarbon under a microscope. A positive intramural spread distance indicated that the furthest tumor cell was distal to the nanocarbon, and a negative value indicated that the tumor cell was proximal to the nanocarbon. The tumor intramural spread distance in fresh tissue during the operation was 1.75 times the tumor intramural spread distance after formalin fixation according to the literature.ResultsAt the distal 5, 6, and 7 o’clock direction, seven (35%), five (25%), and six (30%) patients, respectively, had distal tumor cell intramural spread distance > 0 mm. The mean and 95% confidence interval of tumor cell intramural spread distance in fresh tissue during operation was − 0.3 (95%CI − 4.0 ~ 3.4) mm, − 0.9 (95%CI − 3.4 ~ 1.7) mm, and − 0.4 (95%CI − 3.5 ~ 2.8) mm, respectively. The maximal intraoperative intramural spread distances in fresh tissue were 8.8, 7, and 7 mm, respectively.ConclusionsThe intraoperative distance between the distal resection line and the visible margin of the rectal tumor after radiotherapy should not be less than 1 cm to ensure oncological safety.

Surgical Treatment of Bone Sarcoma

Simple SummaryEven today, a malignant bone tumor is still a threatening condition for the patient. Such tumors are difficult to treat and they require an interdisciplinary approach to ensure the best possible outcome. This review article provides an overview of the three dominating bone sarcoma entities: osteosarcoma, chondrosarcoma, and Ewing sarcoma. Their prognoses and main pillars of treatment (chemotherapy, radiotherapy, surgery) are laid out with a special focus on the surgical management of this condition. Five cases are described to illustrate different surgical strategies such as biological reconstruction and implantation of a megaprosthesis. Finally, an outline of future developments in the field of tumor surgery is presented with a special focus on technical innovations to help improve surgical outcome and implant survival.Bone sarcomas are rare primary malignant mesenchymal bone tumors. The three main entities are osteosarcoma, chondrosarcoma, and Ewing sarcoma. While prognosis has improved for affected patients over the past decades, bone sarcomas are still critical conditions that require an interdisciplinary diagnostic and therapeutic approach. While radiotherapy plays a role especially in Ewing sarcoma and chemotherapy in Ewing sarcoma and osteosarcoma, surgery remains the main pillar of treatment in all three entities. After complete tumor resection, the created bone defects need to be reconstructed. Possible strategies are implantation of allografts or autografts including vascularized bone grafts (e.g., of the fibula). Around the knee joint, rotationplasty can be performed or, as an alternative, the implantation of (expandable) megaprostheses can be performed. Challenges still associated with the implantation of foreign materials are aseptic loosening and infection. Future improvements may come with advances in 3D printing of individualized resection blades/implants, thus also securing safe tumor resection margins while at the same time shortening the required surgical time. Faster osseointegration and lower infection rates may possibly be achieved through more elaborate implant surface structures.

The safe surgical margin in Ewing’s sarcoma

IntroductionThere is recent evidence advocating the use of post-chemotherapy MRI for safe resection of primary bone sarcoma in providing a clear margin of disease. This paper challenges this view by providing evidence obtained from comparing surgical resection margin measurements calculated off the pre- and post-chemotherapy MRIs to the post-operative histological analysis. MethodA retrospective patho-radiological analysis of 10 patients treated for long bone Ewing's sarcoma. The pre- and post-chemotherapy MRI radiological measurements were correlated with the post-operative gross and microscopic histological specimens with the principle aim of determining which represented the accurate histological extent of disease and therefore which image set should be used in determining the surgical resection margins. ResultsIn the 10 cases there was a discrepancy in the extent of pathological disease on comparative histological and radiological assessment. The mean age at presentation was 19.5years [4–45 years], with a female bias (n = 7/10). The lower limbs were more commonly involved than the upper limb (femur n = 2/10, tibia n = 3/10, fibula n = 2/10, humerus n = 2/10, ulna n = 1/10). There was no correlation between the percentage reduction in measured volume/length of pathological bone on sequential MRI and the percentage necrosis on histology. The average discrepancy between the length of pathological bone on histology and on MRI was 2.7 cm. Using the baseline pre-chemotherapy MRI to plan the surgical resection margins, 7/10 patients had their surgical resection margins through radiologically clear but pathologically abnormal bone (without histological evidence of residual tumour). Had the post-chemotherapy MRI been used a further 3 patients would have had their tumour resected through pathologically abnormal bone. No patients had or would have had tumour resected through residual tumour. ConclusionsThe use of the post-chemotherapy MRI for planning surgical resection margins increases the risk of resecting through histologically abnormal bone that may have been previously contaminated by tumour, without significant benefit of preserving sufficient bone to facilitate joint or physeal sparing surgery. The evidence from this study supports current guidelines recommending the use of pre-chemotherapy MRI to plan safe surgical resection margins in Ewing's sarcoma.

Advantages and disadvantages of transthoracic approach for adenocarcinoma of the esophagogastric junction

Adenocarcinoma of the esophaogastric junction (AEG) has anatomical characteristics of spanning two organs and anatomical sites. Thoracic surgery and gastrointestinal surgery aim at the safe resection margin of esophagus, the scope of lower mediastinal lymph node dissection and whether transthoracic surgery will increase complications. However, there are great differences and controversies in the surgical approach, surgical method, lymph node dissection and extent of resection of AEG. For Siewert II AEG via abdominal mediastinal approach, due to the limitation of exposure and the difficulty of operation, it is difficult to acquire a satisfactory proximal resection margin, and very difficult to dissect the inferior mediastinal lymph nodes. The transthoracic approach can provide adequate exposure, reduce the difficulty of operation, obtain satisfactory resection margin of esophagus and allow lower mediastinal lymph node dissection, which may bring better prognosis. Although transthoracic approach may increase the incidence of pulmonary infection, the standard development of thoracoscopic technology will overcome the disadvantage of transthoracic approach for Siewert II AEG.

Tumours of Nasal Septum: A Retrospective Study of 32 Patients.

Objective: Tumours of the nasal septum are a rare and heterogeneous group of lesions in the sinonasal tract. The management of the different lesions of this site is debated. The aim of this study is to share our experience on a rare clinical condition and stimulate other centres to publish theirs. Methods: We retrospectively analysed the databases of sinonasal tumours treated at the Sections of Otolaryngology (ENT) of two University Hospitals (Palermo and Genova) between 2012 and 2020. Results: From the two databases, a cohort of 32 patients with tumours of nasal septum were selected. All patients underwent an endoscopic examination. Large tumours underwent preoperative computed tomography (CT) scan without contrast medium. In 22 (68.7%) cases, the preoperative radiologic evaluation also included magnetic resonance imaging (MRI) with gadolinium to obtain a better differentiation of the lesions and study the vascular pattern. All the large lesions were biopsied under endoscopic guidance using local anaesthesia; the same approach was used to remove the tumours and their attachment with safe resection margins. Conclusions: While malignant lesions require an excision of the mass with resection of all layers of the nasal septum, benign lesions must be typed according to histological considerations in order to plan the most appropriate type of surgical resection.

Resection margin of colorectal cancer surgery

The judgment of surgical resection margins is an important factor affecting local recurrence and distant metastasis of colorectal cancer, which is crucial to the prognosis of patients. How to select a standard and ideal surgical resection margin is a challenge for colorectal cancer surgeons. Surgical resection margins for colorectal cancer include longitudinal resection margin (LRM) and circumferential resection margin (CRM), and the distance of safe resection margins varies according to different guidelines. Surgical resection margins are mainly evaluated by preoperative imaging, operative experience, operative type, hyperspectral imaging (HPI) and fluorescence angiography (FA), and postoperative pathology. It is the constant pursuit of colorectal cancer surgeons to pay attention to the safe resection margins in colorectal cancer surgery to reduce local recurrence and distant metastasis.

Precise resection and defect repair of external nose malignant tumor

Objective: To explore the methods for the accurate resection of malignant tumors of the external nose, and the accurate evaluation and repair of tissue defects. Methods: We collected 48 cases with nasal malignant tumors treated in 980 Hospital, Joint Support Force of the People's Liberation Army from January 2010 to June 2020, including 28 males and 20 females, aged 36-86 years. The pathological types of tumors included basal cell carcinomas (n=29), squamous cell carcinomas (n=11), trichilemmal carcinomas(n=6), denoid cystic carcinoma (n=1) and non-Hodgkin lymphoma (n=1). Tumor resection was mainly based on the traditional extended resection determined by the safety margin, and Mohs surgery was used to minimize the scope of resection, for the margin that significantly affected the repairing results, such as the lesion adjacent to the nasal alar margin, nasal columella or deep easy-penetrating margin. All cases obtained tumor resection and primary/secondary defect reconstruction. Results: According to the pathological type and tumor size, the safe resection margin was mainly 4-10 mm, and Mohs surgery was used in 24 cases. Limited-size defects in 38 cases were repaired with double-leaf flaps, kite flaps, nasal dorsum brow flaps, nasolabial flaps or free tissues. Among 10 cases with compound defects, 8 cases were repaired with frontal flaps, including 4 cases with single frontal flaps, 2 cases with additional titanium mesh stent reconstruction and 2 cases with over and out frontal flaps. During follow-up of 1 to 10 years, all the flaps survived without flap necrosis, and the postoperative nasal contour and ventilation were satisfactory. One patient had tumor recurrence 18 months after operation, 2 patients died of cardiovascular and cerebrovascular diseases, and other patients survived without tumors. Conclusions: Mohs surgery can basically meet the requirements for precise resection of external nasal malignant tumors. Individualized application of adjacent tissue flaps and various frontal flaps is a reasonable choice to achieve the satisfactory outcome of external nasal repair and to take into account the complexity of operation.

Role of Donuts and Safe Resection Margins in Rectal Cancer Surgery

Resection margins in rectal cancer surgery have a pivotal role in assessing the adequacy of surgery as well as playing an important role in determining the prognosis for the patient. With better understanding of tumor biology, more importance is being laid on circumferential resection margin (CRM) rather than distal/proximal resection margin. Positive CRM is an important predictor for increased local recurrence rates. The length of safe distal resection margin in rectal cancer surgery has reduced significantly over the past few decades, with no significant change in the prognosis of patients. To avoid permanent stoma, more and more sphincter saving procedures are being performed, and this has been made possible as a result of more and more use of staplers. While using staplers, donuts are produced from the two resected ends and there is controversy whether these should be sent for histopathological examination or not. In this article, we discuss the importance of resection margins and donuts in rectal cancer surgery.

Omission of neoadjuvant radiotherapy for clinical T2/N1 and T3N0/1 middle and low rectal cancers with safe circumferential resection margins.

PurposeFor moderately advanced rectal cancers with safe circumferential margins, the oncologic benefit of neoadjuvant radiotherapy must be reconsidered because of the possibility of overtreatment, resulting in complications from radiotoxicity. To evaluate the oncologic safety of the omission of neoadjuvant radiotherapy for moderately advanced rectal cancers, we evaluated and compared the prognoses of patients who underwent radical resection with and without neoadjuvant radiotherapy for T2/N1 and T3N0/1 middle and low rectal cancers with safe circumferential resection margins.MethodsWe retrospectively enrolled 66 patients who underwent radical resection for clinical (c) T2N1 and T3N0/1 middle and low rectal cancers between 2008 and 2014. Patients with distant metastasis; cT4, cN2, or positive lateral pelvic lymph nodes; positive circumferential resection margin; signet-ring cell carcinoma; cT1/2N0; or those who had received adjuvant radiotherapy were excluded. The clinical and pathological characteristics and 5-year oncologic outcomes of the no-radiotherapy (n = 34) and radiotherapy (n = 32) groups were compared.ResultsThe rates of abdominoperineal resection and ileostomies and the proportion of patients who received adjuvant chemotherapy were significantly higher in the radiotherapy group. There were no significant differences in tumor location, clinical stage, surgery type, pathologic N stage, anastomotic leakage, or long-term oncologic outcomes including 5-year disease-free survival, overall survival, and local recurrence and distant metastasis rates between both groups.ConclusionThe oncologic benefit of neoadjuvant radiotherapy for cT2/N1 and T3N0/1 middle and low rectal cancers with safe circumferential resection margins is considered unclear, and it can be omitted to prevent radiotoxicity and facilitate prompt essential treatment.

Laparoscopic versus Open Liver Resection for Posterosuperior Segments Located Hepatocellular Carcinoma in Cirrhotic Patients: A Propensity Score-Matching Analysis

Background: Laparoscopic liver resections in posterosuperior segments (PSS) S7-S8 remains a technically demandig procedure and should be performed only in expert centers by skilled laparoscopic surgeons. Technical difficulties are related to the curvilinear liver surfaces, the limited working space to identify safe resection margins and to achieve bleeding control. The aim of our study was to evaluate the short- and longterm outcomes of Laparoscopic liver resections (LLR) versus open liver resections (OLR) for the treatment of HCC lesions located in PSS. Method: We retrospective analyzed 406 consecutive cirrothic patients underwent laparoscopic (78) vs (328) open resections for HCC in PSS using HeRcOLeS database. Patients were divided into LLR and OLR groups and then, perioperative, postoperative and oncological outcomes were analyzed. Propensity score-matched analysis was used to match groups for preoperative characteristics, liver functions tests, hcc position and surgical procedure. Results: After propensity score matching 116 patients were enrolled, 58 in the LLR group and 58 in the OLR group. Operative time was lower in the OLR group than in the LLR group (245± 82 vs 265±118 , p= 0.001) as Pringle Maneuver duration that was lower in OLR group than in the LLR one (41±21 vs 57± 15 , p=0.001). There were no significant differences between the two groups in terms of complications, hospital stay, post-operative mortality, recurrence and overall survival. Coclusions: LLR of tumours in PSS is a safe and feasible procedure for HCC, without compromising oncological safety and, with similar postoperative outcomes than open techniques.

"Split" combined subsegmentectomy: A case series.

BackgroundClinically, some specific pulmonary nodules have safe resection margins that are located in multiple subsegments in the center of lung lobe. It is therefore difficult to ensure the resection margins through conventional combined subsegmentectomy or wedge resection, and thus lobectomy is required. For these types of pulmonary nodules, “split” operation was performed to fully inflate the reserved lung tissues on both sides. This study aimed to preliminarily assess the feasibility and safety of “split” operation.MethodsCases with these types of pulmonary nodules were selected. Some of the cases were subjected to “split” operation and the operation conditions, including operation time, bleeding amount, length of hospital stay, computed tomography (CT) reexaminations, and pulmonary function, were analyzed.ResultsThe “split” operation was performed and successfully completed for seven patients. There was no case of conversion to thoracotomy and the median operation time, bleeding amount, and length of hospital stay were 219 min, 30.0 ml, and 4 days, respectively. No death or pulmonary complications such as pulmonary infection, lung torsion, and bronchopleural fistula occurred, and only one patient had incision fat liquefaction. After 3 months, the median percentage of preserved pulmonary function was 85.8% and a CT scan showed that the reserved lung tissues of the seven patients were well inflated and without obvious imaging findings of atelectasis.Conclusion“Split” combined subsegmentectomy can be used as a new and safe operative method for deep pulmonary nodules with safe resection margins involving multiple subsegments in the center of the lung lobe.

Detecting pulmonary nodules by using ultrasound multiple scattering.

Although X-Ray Computed Tomography (CT) is widely used for detecting pulmonary nodules inside the parenchyma, it cannot be used during video-assisted surgical procedures. Real-time, non-ionizing, ultrasound-based techniques are an attractive alternative for nodule localization to ensure safe resection margins during surgery. Conventional ultrasound B-mode imaging of the lung is challenging due to multiple scattering. However, the multiple scattering contribution can be exploited to detect regions inside the lung containing no scatterers. Pulmonary nodules are homogeneous regions in contrast to the highly scattering parenchyma containing millions of air-filled alveoli. We developed a method relying on mapping the multiple scattering contribution inside the highly scattering lung to detect and localize pulmonary nodules. Impulse response matrices were acquired in ex-vivo pig and dog lungs using a linear array transducer to semi-locally investigate the backscattered field. Extracting the multiple-scattering contribution using singular-value decomposition and combining it with a depression detection algorithm allowed us to detect and localize regions with less multiple scattering, associated with the nodules. The feasibility of this method was demonstrated in five ex-vivo lungs containing a total of 20 artificial nodules. Ninety-five percent of the nodules were detected. Nodule depth and diameter significantly correlated with their ex-vivo CT-estimated counterparts (R = 0.960, 0.563, respectively).

BREAST-CONSERVING SURGERY AFTER NEOADJUVANT CHEMOTHERAPY IN BREAST CANCER PATIENTS

The purpose of the study was to present the most recent data on the outcomes of breast-conserving surgery after neoadjuvant chemotherapy for breast cancer patients.Material and methods. We analyzed relevant publications available in the pubmed, cochrane library, e-library databases between 1990 and 2020, and 24 of them were used to write this review.Results. Neoadjuvant chemotherapy for breast cancer patients is currently a widespread treatment option. The main advantage of this type of treatment for patients with early stage breast cancer is the feasibility of performing breast-conserving surgery in cases of partial or complete clinical response and, therefore, the improvement of the quality of life of patients with equivalent rates of disease-free survival compared to radical mastectomies.Conclusion. Numerous studies have shown that breast-conserving surgery following neoadjuvant chemotherapy is the safe surgery with good oncologic outcomes and an alternative to radical mastectomies in breast cancer patients. However, further studies are required to determine the optimal safe resection margin width in patients with complete and partial responses to neoadjuvant chemotherapy.

In situ DESI-MSI lipidomic profiles of mucosal margin of oral squamous cell carcinoma.

BackgroundAlthough there is consensus that the optimal safe margin is ≥ 5mm, obtaining clear margins (≥5 mm) intraoperatively seems to be the major challenge. We applied a molecular diagnostic method at the lipidomic level to determine the safe surgical resection margin of OSCC by desorption electrospray ionisation mass spectrometry imaging (DESI-MSI).MethodsBy overlaying mass spectrometry images with hematoxylin-eosin staining (H&E) from 18 recruited OSCC participants, the mass spectra of all pixels across the diagnosed tumour and continuous mucosal margin regions were extracted to serve as the training and validation datasets. A Lasso regression model was used to evaluate the test performance.FindingsBy leave-one-out validation, the Lasso model achieved 88.6% accuracy in distinguishing between tumour and normal regions. To determine the safe surgical resection distance and margin status of OSCC, a set of 14 lipid ions that gradually decreased from tumour to normal tissue was assigned higher weight coefficients in the Lasso model. The safe surgical resection distance of OSCC was measured using the developed 14 lipid ion molecular diagnostic model for clinical reference. The overall accuracy of predicting tumours, positive margins, and negative margins was 92.6%.InterpretationThe spatial segmentation results based on our diagnostic model not only clearly delineated the tumour and normal tissue, but also distinguished the different status of surgical margins. Meanwhile, the safe surgical resection margin of OSCC on frozen sections can also be accurately measured using the developed diagnostic model.FundingThis study was supported by Nanjing Municipal Key Medical Laboratory Constructional Project Funding (since 2016) and the Centre of Nanjing Clinical Medicine Tumour (since 2014).