Spigelian hernias in the adult population: a systematic review of the literature.

PURPOSE: Spigelian Hernia (SH) is characterized by the protrusion of abdominal viscera or preperitoneal fat through a defect in the spigelian aponeurosis. The objective of this systematic review was to evaluate current literature on Spigelian Hernias in adult population and elucidate their characteristics and preferable management. METHODS: MEDLINE and Scopus bibliographical databases were systematically searched (last search: 31st January 2024) for studies concerning SHs. RESULTS: Two hundred and thirty-four articles met predefined inclusion criteria and concerned collectively 1,629 patients with SHs (58.7% females) with an age of 62.32 ± 17.71 (mean ± SD) years and a BMI of 28.56 ± 7.34 (mean ± SD) kg/m2. A minimally invasive approach was opted at 46.8% of cases, while a mesh was implemented at 67.9% of cases. Postoperative length of hospital stay was 2.8 ± 2.9 (mean ± SD) days. Following individual cases analysis, open surgery was preferable at emergency setting (OR: 2.45; 95% CI: 1.36-4.41; p-value: 0.003), and minimally invasive approaches were associated with shorter length of hospital stay [2 (1-9) vs. 5 (1-22) days; p-value: <0.001]. Overall, thirty-day postoperative morbidity and mortality rates reached 7.0% and 0.3% respectively. CONCLUSION: SH is a rare ventral hernia, and it concerns most frequently overweight women. Open surgical approach is preferred in emergency cases, while laparoscopic surgery is associated with shorter hospitalization. Further comparative studies are necessary to determine optimal surgical approach.

Sex differences in survival following surgery for esophageal cancer: A systematic review and meta-analysis.

The impact of sex on the prognosis of patients with esophageal cancer remains unclear. Evidence supports that sex- based disparities in esophageal cancer survival could be attributed to sex- specific risk exposures, such as age at diagnosis, race, socioeconomic status, smoking, drinking, and histological type. The aim of our study is to investigate the role of sex disparities in survival of patients who underwent surgery for esophageal cancer. A systematic review and meta-analysis of the existing literature in PubMed, EMBASE, and CENTRAL from December 1966 to February 2023, was held. Studies that reported sex-related differences in survival outcomes of patients who underwent esophagectomy for esophageal cancer were identified. A total of 314 studies were included in the quantitative analysis. Statistically significant results derived from 1-year and 2-year overall survival pooled analysis with Relative Risk (RR) 0.93 (95% Confidence Interval (CI): 0.90-0.97, I2 = 52.00) and 0.90 (95% CI: 0.85-0.95, I2 = 0.00), respectively (RR < 1 = favorable for men). In the postoperative complications analysis, statistically significant results concerned anastomotic leak and heart complications, RR: 1.08 (95% CI: 1.01-1.16) and 0.62 (95% CI: 0.52-0.75), respectively. Subgroup analysis was performed among studies with <200 and > 200 patients, histology types, study continent and publication year. Overall, sex tends to be an independent prognostic factor for esophageal carcinoma. However, unanimous results seem rather obscure when multivariable analysis and subgroup analysis occurred. More prospective studies and gender-specific protocols should be conducted to better understand the modifying role of sex in esophageal cancer prognosis.

Statins and statin intensity in peripheral artery disease.

Background: Peripheral artery disease (PAD) affects more than 202 million people worldwide. Several studies have shown that patients with PAD are often undertreated, and that statin utilization is suboptimal. European and American guidelines highlight statins as the first-line lipid-lowering therapy to treat patients with PAD. Our objective with this meta-analysis was to further explore the impact of statins on lower extremities PAD endpoints and examine whether statin dose (high vs. low intensity) impacts outcomes. Patients and methods: We performed a systematic review and meta-analysis according to the PRISMA guidelines. Any study that presented a comparison of use of statins vs. no statins for PAD patients or studies comparing high vs. low intensity statins were considered to be potentially eligible. We excluded studies with only critical limb threatening ischemia (CLTI) patients. The Medline (PubMed) database was searched up to January 31, 2021. A random effects meta-analysis was performed. Results: In total, 39 studies and 275,670 patients were included in this meta-analysis. In total, 136,025 (49.34%) patients were on statins vs. 139,645 (50.66%) who were not on statins. Statin use was associated with a reduction in all cause-mortality by 42% (HR: 0.58, 95% CI: 0.49-0.67, p<0.01) and cardiovascular death by 43% (HR: 0.57, 95% CI: 0.40-0.74, p<0.01). Statin use was associated with an increase in amputation-free survival by 56% (HR: 0.44, 95% CI: 0.30-0.58, p<0.01). The risk of amputation and loss of patency were reduced by 35% (HR: 0.65, 95% CI: 0.41-0.89, p<0.01) and 46% (HR: 0.54, 95% CI: 0.34-0.74, p<0.01), respectively. Statin use was also associated with a reduction in the risk of major adverse cardiovascular events (MACE) by 35% (HR: 0.65, 95% CI: 0.51-0.80, p<0.01) and myocardial infarction rates by 41% (HR: 0.59, 95% CI: 0.33-0.86, p<0.01). Among patients treated with statins, the high-intensity treatment group was associated with a reduction in all cause-mortality by 36% (HR: 0.64, 95% CI: 0.54-0.74, p<0.01) compared to patients treated with low intensity statins. Conclusions: Statin treatment among patients with PAD was associated with a statistically significant reduction in all-cause mortality, cardiovascular mortality, MACE, risk for amputation, or loss of patency. Higher statin dose seems to be associated with improved outcomes.

Management of Morgagni's Hernia in the Adult Population: A Systematic Review of the Literature.

BACKGROUND: Morgagni's hernia (MH) is defined by the protrusion of abdominal viscera through an anterior retrosternal diaphragmatic defect. The objective of this study was to systematically review current literature on MHs in adult population and assess their clinical characteristics and therapeutic approach. METHODS: PubMed and Cochrane bibliographical databases were searched (last search: 15th January 2021) for studies concerning MHs. RESULTS: Inclusion criteria were met by 189 studies that included 310 patients (61.0% females) with an age of 57.37 ± 18.41 (mean ± SD) years. Pulmonary symptoms, abdominal pain, and nausea-vomit were among the most frequent symptomatology. MHs were predominantly right-sided (84.0%), with greater omentum (74.5%) and transverse colon (65.1%) being the most commonly herniated viscera. The majority of cases underwent an open procedure, while 42.3% of patients had a minimally invasive procedure. Abdominal approach was mostly preferred, while a thoracic one was chosen at 20.6% of cases and a thoracoabdominal at 3.2%. Thirty-day postoperative complications were recorded at 29 patients and 30-day mortality was 2.3%. CONCLUSIONS: MH is a rare type of congenital diaphragmatic hernia which rarely manifests in adult population with atypical pulmonary and gastrointestinal symptoms. Surgery is the gold standard for their management. Open surgical approach is preferable in emergency cases, while laparoscopic surgery is favored in elective setting and is associated with shorter hospitalization. Further studies are crucial in order to elucidate etiology and optimal therapeutic approach.

Statin therapy for reduction of cardiovascular and limb-related events in critical limb ischemia: A systematic review and meta-analysis.

High-intensity statins are recommended for patients with peripheral artery disease (PAD). Critical limb ischemia (CLI) is the most advanced presentation of PAD. The benefit of statins in the CLI population is unclear based on the existent studies. Our objective was to perform a systematic review and meta-analysis regarding the efficacy of statin therapy in patients with CLI. PRISMA guidelines were followed. PubMed, EMBASE, and Cochrane CENTRAL databases were reviewed up to April 30, 2019. The primary outcomes included amputation rates and all-cause mortality. Secondary outcomes included primary patency rates, amputation-free survival and major adverse cardiac or cerebrovascular events (MACCE). Risk of bias was assessed with the Robins-I tool for observational studies. A random-effects model meta-analysis was performed. Heterogeneity was assessed with I2. Funnel plots and Egger's test were used to assess publication bias. Nineteen studies including 26,985 patients with CLI were included in this systematic review. Among patients with known data on statin status, 12,292 (49.6%) were on statins versus 12,513 (50.4%) not on statins. Patients treated with statins were 25% less likely to undergo amputation (HR 0.75; 95% CI: 0.59-0.95; I2 = 79%) and 38% less likely to have a fatal event (HR 0.62; 95% CI: 0.52-0.75; I2 = 41.2%). Statin therapy was also associated with increased overall patency rates and lower incidence of MACCE. There was substantial heterogeneity in the analysis for amputation and amputation-free survival (I2 > 70%). In conclusion, statins are associated with decreased risk for amputation, mortality, and MACCE, as well as increased overall patency rates among patients with CLI. Future studies should assess whether other lipid-lowering medications in addition to high-intensity statins can further improve outcomes among patients with CLI. (PROSPERO registration number: CRD42019134160).

Pseudoachalasia: a systematic review of the literature.

Pseudoachalasia, also known as secondary achalasia, is a clinical condition mimicking idiopathic achalasia but most commonly caused by malignant tumors of gastroesophageal junction (GEJ). Our aim was to systematically review and present all available data on demographics, clinical features, and diagnostic modalities involved in patients with pseudoachalasia. A systematic search of literature published during the period 1978-2019 was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (end-of-search date: June 25th, 2019). Two independent reviewers extracted data with regards of study design, interventions, participants, and outcomes. Thirty-five studies met our inclusion criteria and were selected in the present review. Overall, 140 patients with pseudoachalasia were identified, of whom 83 were males. Mean patient age was 60.13 years and the mean weight loss was 13.91 kg. A total of 33 (23.6%) patients were wrongly 'treated' at first for achalasia. The most common presenting symptoms were dysphagia, food regurgitation, and weight loss. The median time from symptoms' onset to hospital admission was 5 months. Most common etiology was gastric cancer (19%). Diagnostic modalities included manometry, barium esophagram, endoscopy, and computed tomography (CT). Pseudoachalasia is a serious medical condition that is difficult to be distinguished from primary achalasia. Clinical feature assessment along with the correct interpretation of diagnostic tests is nowadays essential steps to differentiate pseudoachalasia from idiopathic achalasia.

Mortality after endovascular treatment of infrarenal abdominal aortic aneurysms - the newer the better?

Although endovascular repair of infrarenal abdominal aortic aneurysms (EVAR) presents a delicate alternative treatment for abdominal aortic aneurysms (AAA) with lower perioperative mortality, its long-term efficacy remains a matter of concern. The purpose of this study was to evaluate the currently reported mortality evidence after EVAR and to examine the possible effect of aneurysm status and the study period on mortality rates. The PubMed and Cochrane bibliographical databases were thoroughly searched for studies reporting on more than 1 000 patients with non-ruptured or ruptured infrarenal AAA, treated with EVAR from August 1991 to September 2016. A total of 10 910 titles/abstracts were retrieved and 121 studies were deemed relevant. Twenty-six studies met the inclusion criteria and reported on 354 500 patients with a mean age of 74.6 years. Almost all of the studies referred to elective EVAR and the mean aneurysm size was 5.58 cm. The most common early complication for elective EVAR was perioperative bleeding (1.9 %), whereas hospital-acquired pneumonia was a major concern in urgent EVAR (28.5 %). Conversion rate to open surgery was 1.2 %. The 30-day all-cause mortality rate was 4.84 % (1.7 % for non- ruptured aneurysms, 33.8 % for ruptured aneurysms).The overall all-cause late mortality in a mean follow-up period of 23.8 months was 19.1 %. The aneurysm-related late mortality rate was 3.4 %. With respect to the time period of patient enrollment, studies reporting on patients recruited before 2006 were found to face more secondary complications and higher late mortality rates than patients enrolled after 2005.The endovascular treatment of large and anatomically suitable infrarenal AAA in selected patients remains a safe alternative to open repair. Our findings demonstrate that newer studies show better long-term outcomes than the older ones, proposing a possible improvement of EVAR techniques and perioperative care and providing encouraging evidence for a wider application of EVAR.

Inflammatory fibroid polyp of the esophagus: a systematic review.

INTRODUCTION: Esophageal inflammatory fibroid polyp (IFP) is a rare benign tumor of the gastrointestinal tract with limited available data on clinicopathologic features and treatment strategies. EVIDENCE ACQUISITION: A systematic review of the literature in PubMed/Medline and Scopus databases was performed for articles concerning esophageal IFP in adult population. EVIDENCE SYNTHESIS: A total of 16 studies were identified, involving 16 patients with a Male-Female Ratio of 3:1 and mean age of 50.38 years. Clinical presentation of esophageal IFP included progressive dysphagia in 56.3% of cases, with additional symptoms such as epigastric and retrosternal pain, weight loss, vomiting, and melena. Diagnostic modalities involved endoscopy in all cases, with endoscopic ultrasound (EUS) employed in 50% of cases and tissue biopsy performed during endoscopy in 87.5% of the patients. Therapeutic approach of esophageal IFP consisted of surgical resection in 75% of the patients and endoscopic resection in the remaining 25%, with various surgical procedures employed based on tumor location. Follow-up data, available for 11 patients over a median duration of 15.5 months, indicated two instances of recurrence following endoscopic resection, while the other nine patients remained asymptomatic with no evidence of recurrence. CONCLUSIONS: Esophageal IFP is a rare benign tumor of the gastrointestinal tract presenting with dysphagia, regurgitation, and heartburn. Resection, either endoscopic or surgical, is the primary treatment approach. Prognosis for esophageal IFP is favorable, with low recurrence rates. Further research is required to investigate potential risk factors and etiology for this lesion, and to explore novel therapeutic approaches that may improve patient outcomes.

Deep Learning for Image Analysis in the Diagnosis and Management of Esophageal Cancer.

Esophageal cancer has a dismal prognosis and necessitates a multimodal and multidisciplinary approach from diagnosis to treatment. High-definition white-light endoscopy and histopathological confirmation remain the gold standard for the definitive diagnosis of premalignant and malignant lesions. Artificial intelligence using deep learning (DL) methods for image analysis constitutes a promising adjunct for the clinical endoscopist that could effectively decrease BE overdiagnosis and unnecessary surveillance, while also assisting in the timely detection of dysplastic BE and esophageal cancer. A plethora of studies published during the last five years have consistently reported highly accurate DL algorithms with comparable or superior performance compared to endoscopists. Recent efforts aim to expand DL utilization into further aspects of esophageal neoplasia management including histologic diagnosis, segmentation of gross tumor volume, pretreatment prediction and post-treatment evaluation of patient response to systemic therapy and operative guidance during minimally invasive esophagectomy. Our manuscript serves as an introduction to the growing literature of DL applications for image analysis in the management of esophageal neoplasia, concisely presenting all currently published studies. We also aim to guide the clinician across basic functional principles, evaluation metrics and limitations of DL for image recognition to facilitate the comprehension and critical evaluation of the presented studies.

Pharmaceutical Quality by Design Approach to Develop High-Performance Nanoparticles for Magnetic Hyperthermia.

Magnetic hyperthermia holds significant therapeutic potential, yet its clinical adoption faces challenges. One obstacle is the large-scale synthesis of high-quality superparamagnetic iron oxide nanoparticles (SPIONs) required for inducing hyperthermia. Robust and scalable manufacturing would ensure control over the key quality attributes of SPIONs, and facilitate clinical translation and regulatory approval. Therefore, we implemented a risk-based pharmaceutical quality by design (QbD) approach for SPION production using flame spray pyrolysis (FSP), a scalable technique with excellent batch-to-batch consistency. A design of experiments method enabled precise size control during manufacturing. Subsequent modeling linked the SPION size (6-30 nm) and composition to intrinsic loss power (ILP), a measure of hyperthermia performance. FSP successfully fine-tuned the SPION composition with dopants (Zn, Mn, Mg), at various concentrations. Hyperthermia performance showed a strong nonlinear relationship with SPION size and composition. Moreover, the ILP demonstrated a stronger correlation to coercivity and remanence than to the saturation magnetization of SPIONs. The optimal operating space identified the midsized (15-18 nm) Mn0.25Fe2.75O4 as the most promising nanoparticle for hyperthermia. The production of these nanoparticles on a pilot scale showed the feasibility of large-scale manufacturing, and cytotoxicity investigations in multiple cell lines confirmed their biocompatibility. In vitro hyperthermia studies with Caco-2 cells revealed that Mn0.25Fe2.75O4 nanoparticles induced 80% greater cell death than undoped SPIONs. The systematic QbD approach developed here incorporates process robustness, scalability, and predictability, thus, supporting the clinical translation of high-performance SPIONs for magnetic hyperthermia.

Bioactive Silicon Nitride Implant Surfaces with Maintained Antibacterial Properties.

Silicon nitride (Si3N4) is a promising biomaterial, currently used in spinal fusion implants. Such implants should result in high vertebral union rates without major complications. However, pseudarthrosis remains an important complication that could lead to a need for implant replacement. Making silicon nitride implants more bioactive could lead to higher fusion rates, and reduce the incidence of pseudarthrosis. In this study, it was hypothesized that creating a highly negatively charged Si3N4 surface would enhance its bioactivity without affecting the antibacterial nature of the material. To this end, samples were thermally, chemically, and thermochemically treated. Apatite formation was examined for a 21-day immersion period as an in-vitro estimate of bioactivity. Staphylococcus aureus bacteria were inoculated on the surface of the samples, and their viability was investigated. It was found that the thermochemically and chemically treated samples exhibited enhanced bioactivity, as demonstrated by the increased spontaneous formation of apatite on their surface. All modified samples showed a reduction in the bacterial population; however, no statistically significant differences were noticed between groups. This study successfully demonstrated a simple method to improve the in vitro bioactivity of Si3N4 implants while maintaining the bacteriostatic properties.

Video-assisted thoracoscopic versus open sleeve lobectomy for non-small cell lung cancer: A systematic review and meta-analysis from six comparative studies.

BACKGROUND: Lung sleeve resection is indicated for centrally located lung tumors, especially for patients who cannot tolerate pneumonectomy. With video-assisted thoracoscopic surgery (VATS) being increasingly implemented for a wide variety of thoracic pathologies, this study aims to compare the intraoperative, postoperative, and long-term outcomes of VATS and open bronchial sleeve lobectomy for non-small cell lung cancer (NSCLC). METHODS: The MEDLINE (via PubMed), Cochrane Library, and Scopus databases were searched. Original clinical studies, comparing VATS and open sleeve lobectomy for NSCLC were included. Evidence was synthesized as odds ratios for categorical and weighted mean difference (WMD) for continuous variables. RESULTS: Our analysis included six studies with non-overlapping populations reporting on 655 patients undergoing bronchial sleeve lobectomy for NSCLC (229 VATS and 426 open). VATS sleeve lobectomy was associated with significantly longer operative time ((WMD): 45.85 min, 95% confidence interval (CI): 12.06 to 79.65, p = 0.01) but less intraoperative blood loss ((WMD): -34.57 mL, 95%CI: -58.35 to -10.78, p < 0.001). No significant difference was found between VATS and open bronchial sleeve lobectomy in margin-negative resection rate, number of lymph nodes resected, postoperative outcomes (drainage duration, length of hospital stay, 30-day mortality), postoperative complications (pneumonia, bronchopleural fistula/empyema, prolonged air leakage, chylothorax, pulmonary embolism, and arrhythmia), and long-term outcomes (overall survival, recurrence-free survival). CONCLUSIONS: The limitation of our study arises mainly due to the heterogeneity of the included studies. Nevertheless, VATS bronchial sleeve lung resection constitutes a feasible and safe alternative to the open sleeve lung resection surgery for the management of centrally located lung tumors.

Surgical management of familial pancreatic cancer: a systematic review of the literature.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is the third most common cause of cancer-related mortality. The fact that the vast majority of patients with PDAC are diagnosed at an advanced stage highlights the need of early diagnosis. As hereditary factors are associated with approximately 5% of all PDAC cases, a screening programme to these high-risk individuals (HRI) has been proposed. The aim of screening methods is to identify selected group of patients with morphological abnormalities at an early stage, in order to be treated promptly. In this study, we evaluate the surgical outcomes and the appropriateness of pancreatic resection in HRIs who were selected for screening. METHODS: A systematic literature search of the PubMed, Embase, and Cochrane databases was performed. The clinicopathological features were recorded and evaluated. RESULTS: Six studies were selected for data collection. A total number of 77 patients were identified. Twenty-one patients had a germline mutation, with CDKN2A being the most prominent one (15.6%). Distal pancreatectomy was the most common surgical procedure (42.8%), followed by pancreaticoduodenectomy (33.8%). The mean disease-free survival was 23.6 months and tumour recurrence occurred in 9 patients (11.7%). Disease-specific mortality was 17.8%, while overall mortality was 19.5%. The most frequently reported postoperative diagnosis was PDAC (28 cases, 38.9%), followed by IPMN (23 cases, 31.9%), whereas high-grade PanIN lesions were found in 13 patients (18.1%). CONCLUSION: High-risk individuals for pancreatic cancer, who are eventually operated may have a relatively uneventful postoperative course, however the oncological outcomes are comparable to the general population.

Robot-Assisted Minimally Invasive Esophagectomy versus Open Esophagectomy for Esophageal Cancer: A Systematic Review and Meta-Analysis.

Robot-assisted minimally invasive esophagectomy (RAMIE) was introduced as a further development of the conventional minimally invasive esophagectomy, aiming to further improve the high morbidity and mortality associated with open esophagectomy. We aimed to compare the outcomes between RAMIE and open esophagectomy, which remains a popular approach for resectable esophageal cancer. Ten studies meeting our inclusion criteria were identified, including five retrospective cohort, four prospective cohort, and one randomized controlled trial. RAMIE was associated with significantly lower rates of overall pulmonary complications (odds ratio (OR): 0.38, 95% confidence interval (CI): [0.26, 0.56]), pneumonia (OR: 0.39, 95% CI: [0.26, 0.57]), atrial fibrillation (OR: 0.53, 95% CI: [0.29, 0.98]), and wound infections (OR: 0.20, 95% CI: [0.07, 0.57]) and resulted in less blood loss (weighted mean difference (WMD): -187.08 mL, 95% CI: [-283.81, -90.35]) and shorter hospital stays (WMD: -9.22 days, 95% CI: [-14.39, -4.06]) but longer operative times (WMD: 69.45 min, 95% CI: [34.39, 104.42]). No other statistically significant difference was observed regarding surgical and short-term oncological outcomes. Similar findings were observed when comparing totally robotic procedures only to OE. RAMIE is a safe and feasible procedure, resulting in decreased cardiopulmonary morbidity, wound infections, blood loss, and shorter hospital stays compared to open esophagectomy.

An extremely rare clinical manifestation of acute appendicitis in a nonagenarian patient: lessons still to be learned.

Abstract.

Bochdalek hernias in the adult population: a systematic review of the literature.

BACKGROUND: Bochdalek hernia (BH) is characterized by the protrusion of viscera into thorax through the posterolateral section of the diaphragm. The aim of this study was to systematically review current literature concerning Bochdalek hernias in adults and elucidate their clinical characteristics and preferable treatment approach. METHODS: A search of PubMed and Cochrane bibliographical databases for studies regarding BHs was conducted (last search: 31st March 2021). RESULTS: Predefined inclusion criteria were met by 173 articles and concerned collectively 192 patients (50.5% males) with a mean age of 45.41 ± 20.26 years. Abdominal pain (62.0%) and pulmonary symptoms (41.1%) were the predominant symptomatology of included cases. BHs protruded mainly through the left side of the diaphragm (70.7%), with large intestine (42.7%) and stomach (37.1%) being the most commonly herniated abdominal organs. Most patients (53.8%) underwent an open surgical approach, while abdominal approach was preferred (64.8%). to the thoracic one. Thirty-day postoperative complication were encountered at 21.5% of patients, while 30-day mortality reached 4.4%. CONCLUSION: BH is an extremely rare type of congenital diaphragmatic hernia. It rarely concerns adults, and it manifests with vague gastrointestinal or pulmonary symptoms. Surgical approach is the preferred method for their management with open procedures being preferable at emergency cases, while minimal invasive approach necessitates experienced centers. Further research is needed in order to clarify their true incidence and optimal therapeutic strategy.

Primary Angiosarcoma of the Gastrointestinal Tract: A Systematic Review of the Literature.

Primary Gastrointestinal Angiosarcoma (PGAS) constitutes a rare malignant tumor arising from vascular or lymphatic endothelial cells. The aim of this study was to review the available literature on PGAS and to elucidate its biological behavior and optimal therapeutic approach. PubMed and Embase bibliographical databases were systematically searched (last search April 8th, 2020) for studies concerning PGAS. Ninety-eight studies met our inclusion criteria, involving 110 patients (male/female = 1.5) with an age of 62.40 ± 17.84 (mean, SD) years. They were most frequently located at small (44.5%) and large intestine (35.5%), while 12.7% were multifocal. Surgical resection of the tumor was conducted at 84.0% of the cases combined with adjuvant therapy at 12.3%. One-year cumulative survival was 55.18% (95% CI: 34.33%-71.84%) for large intestine, 30.2% (95% CI: 17.1%-44.5%) for small intestine, whereas multifocal PGAS had a 6-months cumulative survival of 23.08% (95% CI: 5.58%-47.46%). Therefore, PGAS is an extremely rare entity with atypical clinical presentation, challenging diagnosis and aggressive behavior. High clinical suspicion is crucial for its prompt management. Further studies and the development of novel therapeutic agents are required in order to improve survival.

Primary Squamous Cell Carcinoma of Colon and Rectum: A Systematic Review of the Literature.

Background - Objective: Primary colorectal squamous cell carcinoma is an extremely rare neoplasm with an incidence of 0.1 to 0.25 per 1,000 diagnosed colorectal carcinomas.The objective of this study was to evaluate its biological behavior and highlight the role of a surgical approach for its management.MethodsPubMed and Cohrane databases were independently searched (last search: April 10th, 2020) for articles concerning colorectal squamous cell carcinoma in adult population.Results: Seventy-one studies met predefined inclusion criteria and involved 99 patients (54.5% females) with an age of 56.98 ± 12.19 years (mean ± SD). The most frequent site of occurrence was the rectum (63.5%). Open surgery was conducted at 95% of patients, while 21.4% and 30.3% received neoadjuvant and adjuvant therapy respectively.Postoperative complications were developed in 31.3% of patients, while 6.1% died withing the first month following operation. Five-years survival rate was 49.5% (95% CI: 33.7%-63.4%). Female sex (HR: 0.24; 95% CI: 0.11-0.54; p-value: 0.001) and presence of postoperative complications (HR: 4.10; 95%CI: 1.47-1.46; p-value: 0.007) significantly affected the survival.Conclusions Colorectal Squamous Cell Carcinoma is a rare tumor with an aggressive behavior. Surgery is the standard of treatment for the colontumors, while the role of chemoradiotherapy is promising especially for rectal tumors. Further clinical trials are necessary to determine the preferred treatment approach.