The Importance of Extracellular Vesicle Screening in Gastric Cancer: A 2024 Update.

Extracellular vesicles, or EVs, are membrane-bound nanocompartments produced by tumor cells. EVs carry proteins and nucleic acids from host cells to target cells, where they can transfer lipids, proteomes, and genetic material to change the function of target cells. EVs serve as reservoirs for mobile cellular signals. The collection of EVs using less invasive processes has piqued the interest of many researchers. Exosomes carry substances that can suppress the immune system. If the results of exosome screening are negative, immunotherapy will be beneficial for GC patients. In this study, we provide an update on EVs and GC based on ongoing review papers and clinical trials.

The Value of Preoperative C-Reactive Protein to Albumin Ratio as a Prognostic Biomarker in Colon Cancer Patients.

Inflammatory acute phase proteins have been reported to play a crucial role in cancer progression. Various hematologic and inflammatory markers and scores, such as the lymphocyte-to-monocyte ratio, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, systemic inflammation score (SIS), prognostic nutritional index (PNI), Glasgow prognostic score, and, more recently, the Naples prognostic score, have been reported as significant prognostic markers. The aim of this prospective study was to evaluate the prognostic significance of the C reactive protein-to-albumin ratio (CAR) in patients with colon cancer. Materials and Methods: We conducted a prospective observational study on a series of patients who underwent curative surgery for colon cancer. The C reactive protein-to-albumin ratio was determined preoperatively, and we evaluated the correlations between the CAR and various clinical and pathological parameters, as well as the correlation with Overall and Relapse-free survival. Furthermore, we compared the accuracy of the CAR with that of the Naples score. Results: One hundred and ten patients were included in the study. We set 0.4927 as the cut-off value for the CAR according to a receiver operating characteristic curve analysis. Based on the cut-off value, patients were divided into a low CAR group and a high CAR group. The preoperative CAR exhibited statistically significant correlation with tumor volume, T and N stage, number of positive lymph nodes, and grade of tumor differentiation. We also demonstrated a positive correlation between high CAR values and a higher Naples score (p = 0.0005), even when a subgroup analysis was performed for each group individually. Conclusions: The preoperative CAR is a useful prognostic marker in patients with colon cancer. These results may help to design strategies to personalize targeted management approaches among colon cancer patients.

Predictive Factors of Immunotherapy in Gastric Cancer: A 2024 Update.

Many studies on gastric cancer treatment have identified predictors of immunotherapy benefits. This article provides an update on the major developments in research related to predictive factors of immunotherapy for gastric cancer. We used the search term "predictive factors, immunotherapy, gastric cancer" to find the most current publications in the PubMed database related to predictive factors of immunotherapy in gastric cancer. Programmed cell death, genetic, and immunological factors are the main study topics of immunotherapy's predictive factors in gastric cancer. Other preventive factors for immunotherapy in gastric cancer were also found, including clinical factors, tumor microenvironment factors, imaging factors, and extracellular factors. Since there is currently no effective treatment for gastric cancer, we strongly propose that these studies be prioritized.

An international Delphi consensus for surgical quality assessment of lymphadenectomy and anastomosis in minimally invasive total gastrectomy for gastric cancer.

BACKGROUND: Minimally invasive total gastrectomy (MITG) is a mainstay for curative treatment of patients with gastric cancer. To define and standardize optimal surgical techniques and further improve clinical outcomes through the enhanced MITG surgical quality, there must be consensus on the key technical steps of lymphadenectomy and anastomosis creation, which is currently lacking. This study aimed to determine an expert consensus from an international panel regarding the technical aspects of the performance of MITG for oncological indications using the Delphi method. METHODS: A 100-point scoping survey was created based on the deconstruction of MITG into its key technical steps through local and international expert opinion and literature evidence. An international expert panel comprising upper gastrointestinal and general surgeons participated in multiple rounds of a Delphi consensus. The panelists voted on the issues concerning importance, difficulty, or agreement using an online questionnaire. A priori consensus standard was set at > 80% for agreement to a statement. Internal consistency and reliability were evaluated using Cronbach's α. RESULTS: Thirty expert upper gastrointestinal and general surgeons participated in three online Delphi rounds, generating a final consensus of 41 statements regarding MITG for gastric cancer. The consensus was gained from 22, 12, and 7 questions from Delphi rounds 1, 2, and 3, which were rephrased into the 41 statetments respectively. For lymphadenectomy and aspects of anastomosis creation, Cronbach's α for round 1 was 0.896 and 0.886, and for round 2 was 0.848 and 0.779, regarding difficulty or importance. CONCLUSIONS: The Delphi consensus defined 41 steps as crucial for performing a high-quality MITG for oncological indications based on the standards of an international panel. The results of this consensus provide a platform for creating and validating surgical quality assessment tools designed to improve clinical outcomes and standardize surgical quality in MITG.

Telestration with augmented reality improves the performance of the first ten ex vivo porcine laparoscopic cholecystectomies: a randomized controlled study.

INTRODUCTION: The learning curve in minimally invasive surgery (MIS) is steep compared to open surgery. One of the reasons is that training in the operating room in MIS is mainly limited to verbal instructions. The iSurgeon telestration device with augmented reality (AR) enables visual instructions, guidance, and feedback during MIS. This study aims to compare the effects of the iSurgeon on the training of novices performing repeated laparoscopic cholecystectomy (LC) on a porcine liver compared to traditional verbal instruction methods. METHODS: Forty medical students were randomized into the iSurgeon and the control group. The iSurgeon group performed 10 LCs receiving interactive visual guidance. The control group performed 10 LCs receiving conventional verbal guidance. The performance assessment using Objective Structured Assessments of Technical Skills (OSATS) and Global Operative Assessment of Laparoscopic Skills (GOALS) scores, the total operating time, and complications were compared between the two groups. RESULTS: The iSurgeon group performed LCs significantly better (global GOALS 17.3 ± 2.6 vs. 16 ± 2.6, p ≤ 0.001, LC specific GOALS 7 ± 2 vs. 5.9 ± 2.1, p ≤ 0.001, global OSATS 25.3 ± 4.3 vs. 23.5 ± 3.9, p ≤ 0.001, LC specific OSATS scores 50.8 ± 11.1 vs. 41.2 ± 9.4, p ≤ 0.001) compared to the control group. The iSurgeon group had significantly fewer intraoperative complications in total (2.7 ± 2.0 vs. 3.6 ± 2.0, p ≤ 0.001) than the control group. There was no difference in operating time (79.6 ± 25.7 vs. 84.5 ± 33.2 min, p = 0.087). CONCLUSION: Visual guidance using the telestration device with AR, iSurgeon, improves performance and lowers the complication rates in LCs in novices compared to conventional verbal expert guidance.

Robotic-assisted versus laparoscopic bowel anastomoses: randomized crossover in vivo experimental study.

BACKGROUND: Initial learning curves are potentially shorter in robotic-assisted surgery (RAS) than in conventional laparoscopic surgery (LS). There is little evidence to support this claim. Furthermore, there is limited evidence how skills from LS transfer to RAS. METHODS: A randomized controlled, assessor blinded crossover study to compare how RAS naïve surgeons (n = 40) performed linear-stapled side-to-side bowel anastomoses in an in vivo porcine model with LS and RAS. Technique was rated using the validated anastomosis objective structured assessment of skills (A-OSATS) score and the conventional OSATS score. Skill transfer from LS to RAS was measured by comparing the RAS performance of LS novices and LS experienced surgeons. Mental and physical workload was measured with the NASA-task load index (NASA-Tlx) and the Borg-scale. OUTCOMES: In the overall cohort, there were no differences between RAS and LS for surgical performance (A-OSATS, time, OSATS). Surgeons that were naïve in both LS and RAS had significantly higher A-OSATS scores in RAS (Mean (Standard deviation (SD)): LS: 48.0 ± 12.1; RAS: 52.0 ± 7.5); p = 0.044) mainly deriving from better bowel positioning (LS: 8.7 ± 1.4; RAS: 9.3 ± 1.0; p = 0.045) and closure of enterotomy (LS: 12.8 ± 5.5; RAS: 15.6 ± 4.7; p = 0.010). There was no statistically significant difference in how LS novices and LS experienced surgeons performed in RAS [Mean (SD): novices: 48.9 ± 9.0; experienced surgeons: 55.9 ± 11.0; p = 0.540]. Mental and physical demand was significantly higher after LS. CONCLUSION: The initial performance was improved for RAS versus LS for linear stapled bowel anastomosis, whereas workload was higher for LS. There was limited transfer of skills from LS to RAS.

Non-invasive laparoscopic detection of small tumors of the digestive tract using inductive sensors of proximity.

The precise location of gastric and colorectal tumors is of paramount importance for the oncological surgeon as it dictates the limits of resection and the extent of lymphadenectomy. However, this task proves sometimes to be very challenging, especially in the laparoscopic setting when the tumors are small, have a soft texture, and do not invade the serosa. In this view, our research team has developed a new instrument adapted to minimally-invasive surgery, and manipulated solely by the operating surgeon which has the potential to locate precisely tumors of the digestive tract. It consists of an inductive proximity sensor and an electronic block encapsulated into an autoclavable stainless-steel cage that works in tandem with an endoscopic hemostatic clip whose structure was modified to increase detectability. By scanning the serosal side of the colon or stomach, the instrument is capable to accurately pinpoint the location of the clip placed previously during diagnostic endoscopy on the normal bowel mucosa, adjacent to the tumor. In the current in-vivo experiments performed on large animals, the modified clips were transported without difficulties to the point of interest and attached to the mucosa of the bowel. Using a laparoscopic approach, the detection rate of this system reached 65% when the sensor scanned the bowel at a speed of 0.3 cm/s, and applying slight pressure on the serosa. This value increased to 95% when the sensor was guided directly on the point of clip attachment. The detection rate dropped sharply when the scanning speed exceeded 1 cm/s and when the sensor-clip distance exceeded the cut-off value of 3 mm. In conclusion, the proposed detection system demonstrated its potential to offer a swift and convenient solution for the digestive laparoscopic surgeons, however its detection range still needs to be improved to render it useful for the clinical setting.

Development and validity evidence of an objective structured assessment of technical skills score for minimally invasive linear-stapled, hand-sewn intestinal anastomoses: the A-OSATS score.

INTRODUCTION: The aim of this study was to develop a reliable objective structured assessment of technical skills (OSATS) score for linear-stapled, hand-sewn closure of enterotomy intestinal anastomoses (A-OSATS). MATERIALS AND METHODS: The Delphi methodology was used to create a traditional and weighted A-OSATS score highlighting the more important steps for patient outcomes according to an international expert consensus. Minimally invasive novices, intermediates, and experts were asked to perform a minimally invasive linear-stapled intestinal anastomosis with hand-sewn closure of the enterotomy in a live animal model either laparoscopically or robot-assisted. Video recordings were scored by two blinded raters assessing intrarater and interrater reliability and discriminative abilities between novices (n = 8), intermediates (n = 24), and experts (n = 8). RESULTS: The Delphi process included 18 international experts and was successfully completed after 4 rounds. A total of 4 relevant main steps as well as 15 substeps were identified and a definition of each substep was provided. A maximum of 75 points could be reached in the unweighted A-OSATS score and 170 points in the weighted A-OSATS score respectively. A total of 41 anastomoses were evaluated. Excellent intrarater (r = 0.807-0.988, p < 0.001) and interrater (intraclass correlation coefficient = 0.923-0.924, p < 0.001) reliability was demonstrated. Both versions of the A-OSATS correlated well with the general OSATS and discriminated between novices, intermediates, and experts defined by their OSATS global rating scale. CONCLUSION: With the weighted and unweighted A-OSATS score, we propose a new reliable standard to assess the creation of minimally invasive linear-stapled, hand-sewn anastomoses based on an international expert consensus. Validity evidence in live animal models is provided in this study. Future research should focus on assessing whether the weighted A-OSATS exceeds the predictive capabilities of patient outcomes of the unweighted A-OSATS and provide further validity evidence on using the score on different anastomotic techniques in humans.

Multilayered Porous Titanium-Based 3rd Generation Biomaterial Designed for Endosseous Implants.

This work proposes a novel complex multi-layered material consisting of porous titanium as a substrate and a complex coating consisting of a chitosan film engulfing microsphere loaded with growth factors such as BMP2 (bone morphogenic protein 2) and IGF1 (insulin-like growth factor-1). The microspheres were obtained through deposition of dual layers of calcium cross linked pectin-chitosan/pectin polyelectrolyte onto a BSA (bovine serum albumin) gel core. The multilayer was conceived to behave like a 3rd generation biomaterial, by slow delivery of viable growth factors around implants, and to assist the healing of implantation wound and the development of new vital bone. The biologic effect of the delivery of growth factors was studied in vitro, on MSC-CD1 mesenchymal stem cells, and in vivo, on CD1 mice. Proliferation and differentiation of cells were accelerated by growth factors, especially IGF1 for proliferation and BMP2 for differentiation. In vivo tests analyzed histologically and by MicroCT show a more structured tissue around BMP2 samples. The present concept will give the best clinical results if both growth factors are delivered together by a coating film that contains a double population of microcarriers.

Fulminant necrotizing streptococcal myositis with dramatic outcome - a rare case report.

Necrotizing myositis represents a rare, aggressive form of bacterial-induced soft tissue necrotizing infection. We present a fulminant case of a 44-year-old patient with a necrotizing soft tissue infection and a history of rheumatoid arthritis transferred to our service, Cluj-Napoca Emergency County Hospital, from a local hospital where he had been admitted two days before with chills and light-headedness after an accidental minor blunt trauma in the right thigh region. After admission to our hospital and first assessment, broad spectrum antibiotherapy was started with Meropenem, Vancomycin and Metronidazole along with surgical debridement. The evolution was fulminant with rapid development of multiple organ dysfunction syndrome, therefore he was transferred to the intensive care unit, intubated, and started the volemic resuscitation and vasopressor therapy. The blood culture was positive for group A beta-hemolytic streptococcus (GAS) and high dose Penicillin G was added to the therapeutic scheme. Despite all efforts, the patient developed disseminated intravascular coagulation syndrome and died in the next hours. The clinical picture together with the findings from the autopsy were suggestive for a streptococcal toxic shock syndrome developed as a complication of GAS induced necrotizing myositis.

Laparoscopic compatible device incorporating inductive proximity sensors for precise detection of gastric and colorectal small tumors.

The accurate localization of small tumors of the digestive tract is of paramount importance in surgical oncology because it dictates the limits of resection and the extent of lymph node dissection. In this view, we have designed and fabricated a highly efficient sensing laparoscopic instrument focused on precise non-invasive extralumenal intraoperative detection of small colorectal or gastric tumors. The equipment is fully adapted for laparoscopic surgery and consists of an inductive proximity sensor encapsulated into a watertight stainless-steel case that is connected to an electronic functional block dimensionally scaled-down by the desired form and size for optimal surgical manipulation. The sensor-case unit and the electronic block are coupled together using a modular system which allows disconnection of the latter and sterilization by autoclavation of the former, followed by swift plugging of the electronic block just before surgery in a sterile-controlled environment. The instrument works in tandem with a modified endoscopic hemostatic clip which is attached endoscopically, before surgery, in the mucosa proximal and distal to the tumor. By scanning the serosal side of the digestive organ during the laparoscopic surgical procedure, the detector senses the modified clip and thus pinpoints to the location of the tumor. Additional engineering of the standard endoscopic hemostatic clips by coating them with various combinations of metallic alloys of Cu and Zn was necessary to improve the detection range and sensitivity without compromising on their functionality. The clips were also covered with nanometric layers of Au to ensure their biocompatibility. The ex-vivo dry-lab experiments showed a satisfactory detection distance which was later confirmed in ex-vivo wet-lab experiments on animal organs and human surgical specimens.

Colorectal Surgery in Romania during the COVID-19 Pandemic.

As the COVID-19 pandemic extends, its negative consequences on the effectiveness of therapeutic programs - previously assumed by the medical community and imperatively suspended for a difficult-to-predict period of time - are becoming increasingly worrying. In this context, as the evidence-based recommendations are not possible, most of the national and international scientific societies tried to develop balanced recommendations (1-4). The Romanian Society of Coloproctology (SRCP) and the Romanian Association for Endoscopic Surgery (ARCE) have created a working group that, taking into account recent publications, the statements of international academic societies, the national legislative context and the unique experience of countries severely affected by this pandemic (China, Italy, Spain, USA, etc.) proposes for Romania, the following recommendations for medical practice in colorectal surgery during the COVID-19 pandemic. These recommendations are subjected to continuous review, depending on the global and national situation of the pandemic, the particular needs of each hospital, the recommendations of the competent authorities and the evolution of the literature that publishes the conclusions of ongoing clinical trials.

Which is the Optimal Method of Reconstruction After Laparoscopic Right Hemicolectomy, the Intracorporeal or Extracorporeal Anastomosis Technique?

Introduction: The laparoscopic approach to right colectomy is gradually gaining a leading role in the surgical treatment of right colonic diseases. However, not all aspects of the procedure are standardized and the method of reconstruction of the digestive tract is still under debate. The present study critically evaluates the extracorporeal (EA) and intracorporeal (IA) techniques used for creation of the ileocolic anastomosis during a laparoscopic right colectomy. Material and Method: The EA and IA anastomotic techniques are described in detail. The peri operative data of a cohort of consecutive patients operated by our surgical team was retrospectively recorded and analyzed regarding type of anastomosis, the path for transition from EA to IA and the incidence of postoperative complications. Furthermore, an analysis of randomized clinical trials, reviews and meta-analyses that provided a comparative evaluation of EA versus IA was performed to provide a more in-depth integration of our own data into the literature. Results: EA was used at the beginning of our experience but was later replaced by IA which became the favorite anastomotic technique. There was no anastomotic fistula recorded in the EA or IA groups but in our cohort IA was unexpectedly associated with higher incidence of peritoneal drainage, prolonged ileus, surgical site infections, anastomotic bleeding and chyloperitoneum. However, IA allows better visualization of the ileal and colonic stumps, avoids twisting of the anastomosis, prevents extraction-related tearing of the mesocolon and reduces the risk of post operative hernia. Data from the literature also shows that IA is generally associated with earlier postoperative return of bowel function, less morbidity and less postoperative pain. Conclusions: Based on this study and the data currently present in the literature it can not be concluded that IA should be considered as the standard of care for laparoscopic right colectomy. The decision for an EA or IA anastomosis ultimately belongs to the surgeon and is influenced by his surgical skill and experience. The results of ongoing randomized controlled trials on large group of patients may bring more clarity on this issue in the future.

SRED-ARCE Recommendations for Minimally Invasive Interventions During the COVID-19 Pandemic in Romania.

The Romanian Society of Digestive Endoscopy (SRED) and the Romanian Association of Endoscopic Surgery (ARCE) have decided to establish a joint working group to elaborate specific recommendations for organizing the diagnostic and the minimally invasive interventional procedures, in the context of the COVID-19 pandemic. The recommendations are based on the guidelines of the international societies of endoscopy and gastroenterology (ESGE / BSG / ASGE / ACG / AGA), respectively endoscopic surgery (EAES SAGES) (4-8), on the experience of countries severely affected by the pandemic (Italy, France, Spain, USA, Germany, etc.) and they will be applied within the limits of measures imposed at local and governmental level by the competent authorities. On the other hand, these recommendations should have a dynamic evolution, depending on the upward or downward trend of the COVID-19 pandemic at regional and local level, but also according to the findings of professional and academic societies, requiring regular reviews based on the publica tion of further recommendations or international clinical trials. The objectives of the SRED and ARCE recommendations target the endoscopic and laparoscopic surgery activities, to support their non discriminatory used for diagnostic or therapeutic purposes, pursuing the demonstrated benefits of these procedures, in safe conditions for patients and medical staff.

Organ sparing management in rectal cancer. Are we there yet?

BACKGROUND: The "watch and wait" approach has recently been proposed as an alternative to surgery in locally-advanced rectal cancer patients that respond to neo-adjuvant chemoradiotherapy, in order to decrease its negative functional consequences upon the quality of life of these patients. Current methods show low accuracy for the identification of complete responders. MATERIALS AND METHODS: A review of the literature was conducted for articles published up to March 31th, 2019. Relevant studies were identified using bibliographic searches of Pubmed database. The keywords that were used in various combinations were: "neoadjuvant chemoradiotherapy", "non-operative management", "complete pathological response", "rectal cancer", "biomarkers", "staging". RESULTS: Magnetic resonance imaging can identify complete responders with a high accuracy using new protocols like diffusion weighted imaging. Positron emission tomography with 18-fluoro-deoxy-glucose shows a sensitivity of 90.9% and specificity of 80.3% for the prediction of complete pathologic response using the change in standardized uptake value. A panel of 15 metabolites was identified and shows potential to discriminate patient resistance and sensitivity to neo-adjuvant therapy (Area Under the Curve 0.80). Furthermore, pre-treatment peripheral blood neutrophil to lymphocyte ratio below 2 and platelet to lymphocyte ratio below 133.4 are significantly correlated with good tumor response (OR 2.49). Analysis of the pattern of carcinoembryonic antigen (CEA) clearance after neoadjuvant treatment conclude that an exponential decrease of the CEA levels is associated with significant tumor down staging and complete pathologic response. CONCLUSION: New methods of assessing the response to neo-adjuvant therapy in locally-advanced rectal cancer have emerged, showing promising results. Further studies need to assess the best combination between imaging and these biomarkers in order to increase the accuracy and standardize the criteria for non-operative management. KEY WORDS: Biomarkers, Complete pathologic response, Non-Operative management, Rectal cancer, Staging.

The Value of Staging Laparoscopy for Optimal Multidisciplinary Treatment in Patients with Gastric Cancer.

Introduction: Despite improvements in the conventional preoperative tools used for staging of gastric cancer, their accuracy still needs to be improved. Laparoscopy has the potential to visualize and characterize the tumor, the peritoneal cavity and the lymph nodes and thus to better select patients for the optimal treatment strategy. Material and Method: Patients with gastric cancer staged initially with contrast enhanced computer tomography and endoscopic ultrasound were also evaluated by laparoscopy and laparoscopic ultrasound in a distinct preoperative staging procedure. The perioperative data was recorded in a prospective database and was used to decide within the multidisciplinary team the optimal treatment protocol for each patient. The database was retrospectively reviewed for this study. Results: Among the 20 CT-scan M0 patients analyzed, peritoneal carcinomatosis was detected in 15% of the cases. In other 15% of patients laparoscopy upstaged the tumor and directed the patient towards neoadjuvant chemotherapy. Laparoscopic guided percutaneous core biopsies settled the definitive diagnosis in 3 further cases. In total, laparoscopic staging brought important information in 65% of cases and changed the treatment plan in 30% of patients. Conclusions: In the era of neoadjuvant chemotherapy, laparoscopy has the potential to overcome some of the limitations of the conventional staging methods and offers additional informations which finally change the treatment plan in as much as a third of patients with gastric cancer.

Extension of Hepatic Resection Ameliorates Survival in Patients with Type IIIa or IIIb Klatskin Tumors Despite Surgical Complications.

Background: Major hepatectomies for hilar cholangiocarcinoma (HC) are associated with high rates of morbidity and mortality. We aimed to evaluate how and if surgical complications related to extended hepatectomies for HC type III and IV according to Bismuth-Corlette classification influence patients long-term survival. Methods: The files of all patients with major hepatectomy for HC and postoperative complications were retrospectively reviewed. Only patients with a complete postoperative follow up have be taken into account for the study. Postoperative morbidity and mortality, length of hospital stay (LOS) as well as overall survival (OS) and disease free survival (DFS) were recorded. Results: Five patients have been found to respond to all inclusion criteria. Three of them required re-operation with one in hospital death. Two patients are still alive and two other died because of the tumor recurrence with a DFS of 36 and 49 months respectively. The actuarial mean OS for the group was 30 months and the actuarial DFS was 26 months. Conclusions: In patients with HC, extensive resections bring a clearly benefit in terms of survival, even though there is an increase in postoperative morbidity and mortality. However, postoperative complications, if managed susccesfully do not interfere with the long-term survival.

DFT computational correlations on conformational barriers of Zn2+ and Ni2+ chiral meso-(α,ß-unsaturated)- porphyrins.

Correlations between DFT and experimental measurements on Zn2+ and Ni2+ chiral meso-(α,ß-unsaturated)- porphyrins were performed using Kohn-Sham methodology. The exchange-correlation Becke88-Perdew86 functional was used in conjunction with double-zeta Slater basis sets. An accurate description of the electronic processes depending on the metal ion (Zn, Ni) or ligand (perilaldehyde and myrtenal) was made, confirming experimental results in terms of structural and electronic modifications. Moreover, this theoretical study provides a stronger knowledge and interpretation of the dynamical conformational features of the free base, Zn and Ni structures. Fundamental links between the central metallic atom and distortions of the porphyrinic core and ligands were demonstrated, in agreement with experimental data. We observed that the core in ZnPeriP and ZnMyrtP species is almost flat, in comparison with the Ni porphyrinic core, which appeared much more distorted. The type of distortion differs between PeriP and MyrtP ligands, with a combined saddled-ruffled characteristic with the former and a pronounced ruffled twisting for the latter. Finally, conformational energy barriers were extracted by spinning one of the arms in steps of 20° in a 360° dihedral angle. The resulted conformational barriers for NiPeriP or NiMyrtP are lower in energy than for ZnPeriP or ZnMyrtP, in agreement with experimental data.