Colonic Tubular Adenoma with Clear Cell Change: Case Report with Whole-Exome Sequencing and Updated Review of the Literature.

INTRODUCTION: Colorectal tubular adenomas displaying clear cell change are rare entities, with unknown clinical relevance, prognosis, immunohistochemical, and molecular features. CASE PRESENTATION: Hereby we report a case of a 43-year-old female patient with a rectosigmoid polyp. Histologically, conventional dysplasia was visible with scattered areas displaying clear cell change. Whole-exome sequencing (WES) was carried out and revealed high tumour mutation burden and 7 pathogenic mutations, including TP53, APC, FGFR4, EHBP1, IL4R, TYR, and ACTN3. CONCLUSION: Clear cell change may only be present in less than 0.1% of adenomas. Aetiology is not well understood; additionally, few authors suggest autolysis or fixation problems. Our WES resulted in newly found pathogenic mutations, and high mutation burden, proving the lesion's neoplastic origin. Hitherto, neither special stainings nor immunohistochemical markers proved to be useful in the diagnostic process. From a differential diagnostic perspective, enteroblastic differentiation, primary and secondary clear cell adenocarcinoma has to be excluded.

ONEST (Observers Needed to Evaluate Subjective Tests) Analysis of Stromal Tumour-Infiltrating Lymphocytes (sTILs) in Breast Cancer and Its Limitations.

Tumour-infiltrating lymphocytes (TILs) reflect antitumour immunity. Their evaluation of histopathology specimens is influenced by several factors and is subject to issues of reproducibility. ONEST (Observers Needed to Evaluate Subjective Tests) helps in determining the number of observers that would be sufficient for the reliable estimation of inter-observer agreement of TIL categorisation. This has not been explored previously in relation to TILs. ONEST analyses, using an open-source software developed by the first author, were performed on TIL quantification in breast cancers taken from two previous studies. These were one reproducibility study involving 49 breast cancers, 23 in the first circulation and 14 pathologists in the second circulation, and one study involving 100 cases and 9 pathologists. In addition to the estimates of the number of observers required, other factors influencing the results of ONEST were examined. The analyses reveal that between six and nine observers (range 2-11) are most commonly needed to give a robust estimate of reproducibility. In addition, the number and experience of observers, the distribution of values around or away from the extremes, and outliers in the classification also influence the results. Due to the simplicity and the potentially relevant information it may give, we propose ONEST to be a part of new reproducibility analyses.

ONEST (Observers Needed to Evaluate Subjective Tests) suggests four or more observers for a reliable assessment of the consistency of histological grading of invasive breast carcinoma: A reproducibility study with a retrospective view on previous studies.

Histological grade is one of the most important prognosticators of breast cancer which is available for nearly all cases. It also makes part of several multivariable analysis derived combined prognostic profiles despite concerns about its reproducibility. The aims included a reproducibility study of grading in the light of a recently described statistical approach, ONEST (Observers Needed to Evaluate Subjective Tests) and review earlier reproducibility studies in the light of the ONEST analysis. Nine pathologists reviewed 50 core needle biopsies and 50 slides from different excision specimens and recorded the scores for gland (tubule) formation, nuclear pleomorphism and mitotic activity as well as histological grade. Overall percent agreement, Fleiss kappa and the intraclass correlation coefficient (ICC) were used for the analysis of reproducibility. ONEST data and curves were generated from 100 random permutations of the participants. ONEST suggested a minimum of 4 observers for the reliable evaluation of reproducibility for both the scored components and grade in either type of specimen. Our results suggested moderate or moderate to good reproducibility of grading (kappa values of 0.51 for excisions, and 0.54 for biopsies and ICCs of 0.70 and 0.69, respectively) with gland formation being the most and nuclear pleomorphism the worst consistently evaluated feature. In studies with sufficient participants (at least 4) and non-pairwise comparisons in the analysis, the reproducibility of histological grading is fair to moderate, whereas studies with fewer participants or pairwise kappa analysis suggest moderate to almost prefect agreement of the results. ONEST is a valuable complementation of reproducibility analyses.

"Dum spiro spero": clinicopathologic characteristics of SARS-CoV-2 infection / "Dum spiro spero": a SARS-CoV-2-fertozés klinikopatológiája 26 eset kapcsán.

Összefoglaló. Bevezetés: A kórboncolás hozzájárul a súlyos akut légzoszervi szindrómát okozó koronavírus-2 (SARS-CoV-2-) fertozés klinikopatológiai vonatkozásainak megismeréséhez. Célkituzés: A SARS-CoV-2-fertozöttek boncolása során gyujtött tapasztalatok bemutatása. Módszer: Egymást követoen boncolt, védooltásban nem részesült, SARS-CoV-2-fertozött elhunytak klinikai adatait, makro- és mikroszkópos észleleteit összegeztük; a tüdokimetszéseket SARS-CoV-2-nukleokapszid-immunfestéssel vizsgáltuk. Eredmények: A boncolást a halálok megállapítására (n = 14), tumorgyanú (n = 9), illetve törvényi kötelezettség (n = 3) miatt végeztük. A fertozést a klinikai észlelés vagy a boncolás során (n = 4) végzett SARS-CoV-2-nukleinsav-teszt igazolta. A tünetes betegség átlagos hossza 12,9 nap volt. 21 betegnél (medián életkor 69 év; 18 férfi) állt fenn COVID-19-pneumonia, mely 16 esetben önmagában, 4 esetben bakteriális pneumoniával vagy álhártyás colitisszel szövodve okozott halált; 1 antikoagulált pneumoniás beteg heveny retroperitonealis vérzésben halt meg. 3 betegnél a halált disszeminálódott malignus tumor, 1 betegnél coronariathrombosis, 1 mentálisan retardált betegnél pedig pulmonalis emboliás szövodmény okozta. A COVID-19-pneumoniás tüdok nehezek, tömöttek és vörösen foltozottak voltak. Szövettanilag a betegség idotartamától függoen diffúz alveolaris károsodás korai exsudativ vagy késobbi proliferativ fázisa látszott atípusos pneumocytákkal; gyakori volt a microthrombosis (n = 7), a macrothrombosis (n = 5), illetve a pulmonalis embolia (n = 4). A SARS-CoV-2-immunfestés pozitívnak bizonyult az esetek 38,5%-ában, dominálóan az exsudativ fázisban. Minden elhunyt társbetegség(ek)ben szenvedett, így magasvérnyomás-betegségben (n = 17), érelmeszesedésben (n = 14), 2-es típusú diabetesben (n = 8), rosszindulatú daganatban (n = 6), krónikus obstruktív tüdobetegségben (n = 4), elhízásban (n = 3), vesetranszplantáció utáni immunszuppresszióban (n = 3). Következtetés: Az irodalmi adatokkal összhangban, halálos COVID-19-pneumonia túlnyomóan idos, társbetegség(ek)tol sújtott férfiakban alakult ki. A boncolási gyakorlatban a SARS-CoV-2-nukleokapszid-immunfestéstol a diffúz alveolaris károsodás korai fázisában várható pozitivitás. Orv Hetil. 2021; 162(45): 1791-1802. INTRODUCTION: Autopsy is an important tool for the evaluation of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Objectice: The aim of this study was to present our experience with autopsies of patients diagnosed with SARS-CoV-2 infection. METHOD: Clinical data, macroscopic and microscopic findings of consecutive postmortems of non-vaccinated SARS-CoV-2 patients are summarized. Lung samples were evaluated with SARS-CoV-2 nucleocapsid immunohistochemistry. RESULTS: Autopsies were performed to determine the cause of death (n = 14), suspected tumours (n = 9) or due to legal obligation (n = 3). SARS-CoV-2 infection was verified by ante mortem (n = 22) and post mortem (n = 4) polymerase chain reaction. The mean duration of symptomatic disease was 12.9 days. Of 21 patients with COVID-19 pneumonia, 16 died of respiratory failure, 4 had additional bacterial pneumonia or Clostridioides difficile infection, and 1 developed hemorrhagic complication (n = 1). Other causes of death included disseminated malignancies (n = 3), coronary thrombosis (n = 1) and pulmonary embolism (n = 1). The affected lungs were heavy and had patchy red appearance. Exudative or proliferative phases of diffuse alveolar damage (DAD) were detected with atypical pneumocytes. Microthrombosis (n = 7), macrothrombosis (n = 5) and pulmonary embolism (n = 4) were frequent. The SARS-CoV-2 immunohistochemical reaction was positive in 38.5% of cases. All patients had co-morbidities, namely, hypertension (n = 17), atherosclerosis (n = 14), diabetes (n = 8), malignancies (n = 6), chronic obstructive pulmonary diseases (n = 4), obesity (n = 3) and immunosuppression after kidney transplantation (n = 3). CONCLUSION: Fatal COVID-19 pneumonia occurred mostly in elderly males with co-morbidities. In the autopsy practice, the SARS-CoV-2 nucleocapsid immunohistochemical reaction may confirm the infectious etiology in the early phase of DAD. Orv Hetil. 2021; 162(45): 1791-1802.

The additional value of ONEST (Observers Needed to Evaluate Subjective Tests) in assessing reproducibility of oestrogen receptor, progesterone receptor, and Ki67 classification in breast cancer.

The reproducibility of assessing potential biomarkers is crucial for their implementation. ONEST (Observers Needed to Evaluate Subjective Tests) has been recently introduced as a new additive evaluation method for the assessment of reliability, by demonstrating how the number of observers impact on interobserver agreement. Oestrogen receptor (ER), progesterone receptor (PR), and Ki67 proliferation marker immunohistochemical stainings were assessed on 50 core needle biopsy and 50 excision samples from breast cancers by 9 pathologists according to daily practice. ER and PR statuses based on the percentages of stained nuclei were the most consistently assessed parameters (intraclass correlation coefficients, ICC 0.918-0.996), whereas Ki67 with 5 different theoretical or St Gallen Consensus Conference-proposed cut-off values demonstrated moderate to good reproducibility (ICC: 0.625-0.760). ONEST highlighted that consistent tests like ER and PR assessment needed only 2 or 3 observers for optimal evaluation of reproducibility, and the width between plots of the best and worst overall percent agreement values for 100 randomly selected permutations of observers was narrow. In contrast, with less consistently evaluated tests of Ki67 categorization, ONEST suggested at least 5 observers required for more trustful assessment of reliability, and the bandwidth of the best and worst plots was wider (up to 34% difference between two observers). ONEST has additional value to traditional calculations of the interobserver agreement by not only highlighting the number of observers needed to trustfully evaluate reproducibility but also by highlighting the rate of agreement with an increasing number of observers and disagreement between the better and worse ratings.

Clinicopathological Findings on 28 Cases with XP11.2 Renal Cell Carcinoma.

Xp11.2 translocation carcinoma is a distinct subtype of renal cell carcinoma characterized by translocations involving the TFE3 gene. Our study included the morphological, immunohistochemical and clinicopathological examination of 28 Xp11.2 RCCs. The immunophenotype has been assessed by using CA9, CK7, CD10, AMACR, MelanA, HMB45, Cathepsin K and TFE3 immunostainings. The diagnosis was confirmed by TFE3 break-apart FISH in 25 cases. The ages of 13 male and 15 female patients, without underlying renal disease or having undergone chemotherapy ranged from 8 to 72. The mean size of the tumors was 78.5 mm. Forty-three percent of patients were diagnosed in the pT3/pT4 stage with distant metastasis in 6 cases. Histological appearance was branching-papillary composed of clear cells with voluminous cytoplasm in 13 and variable in 15 cases, including one tumor with anaplastic carcinoma and another with rhabdoid morphology. Three tumors were labeled with CA9, while CK7 was negative in all cases. Diffuse CD10 reaction was observed in 17 tumors and diffuse AMACR positivity was described in 14 tumors. The expression of melanocytic markers and Cathepsin K were seen only in 7 and 6 cases, respectively. TFE3 immunohistochemistry displayed a positive reaction in 26/28 samples. TFE3 rearrangement was detected in all the analyzed cases (25/25), including one with the loss of the entire labeled break-point region. The follow-up time ranged from 2 to 300 months, with 7 cancer-related deaths. In summary, Xp11.2 carcinoma is an uncommon form of renal cell carcinoma with a variable histomorphology and rather aggressive clinical course.

[Sudden cardiac death due to sarcoidosis. Case report]. / Hirtelen szívhalál sarcoidosis következtében.

Sarcoidosis is a systemic granulomatous disease of unknown aetiology, which is characterized by bilateral hilar lymphadenopathy and pulmonary disease. Clinically detected cardiac involvement occurs in 5% of sarcoid patients, although cardiac manifestations are discovered in 25% of the cases at autopsy. Sarcoid heart disease frequently causes atrioventricular block. The authors present the case of a 44-year-old man with bradycardia. On admission, second degree Mobitz II, then third degree atrioventricular block was diagnosed. Coronarography showed normal coronary arteries. 2.5 years following artificial Biotronik Entovis DR type pacemaker implantation, sudden cardiac death occurred. Autopsy revealed sarcoidosis with cardiac, pulmonary, splenic, renal and lymph node involvement. In case of young or middle-aged patients with atrioventricular block, it is best to search for other causes if the most common coronary origin can be excluded. Orv Hetil. 2017; 158(27): 1067-1070.

The Petersen prognostic index revisited in Dukes B colon cancer--Inter-institutional differences.

A prognostic index (Petersen index, PI) was created for patients with pT3-4 pN0 M0 (Stage II, Dukes' B) colon cancers to distinguish between patients with better and worse outcome, and to help in recommending adjuvant chemotherapy for high risk patients in this stage. The prognostic value of the PI was evaluated in two independent retrospective series of stage II (Dukes' B) colon cancer patients. The parameters defining the PI (venous invasion, peritoneal involvement, circumferential margin involvement, perforation through the tumour) and performance of the PI were compared in two institutions. The two series of patients consisted of 127 and 87 patients. Venous invasion was more frequently detected at one of the centres (p<0.01) and tumour perforation was more frequent at the other (p<0.01). There were no significant differences in the 5-year survival estimates of all patients (p=0.19), and of either the low PI value groups (p=0.52) or that of the high PI value groups (p=0.99) between the two sites. In contrast, there were significant differences in the survival estimates between patients of the low PI category and those of the high PI category altogether (p<0.01) and in either centre. Although, it was expected that differences in the frequency of the parameters involved in the PI would influence its performance, this was not confirmed by the data. Our results suggest that using the PI may be of value in prognostic factor based therapy selection of colon carcinoma patients.

Elastic staining does not assist detection of venous invasion in cutaneous melanoma.

The aim of the present study was to determine the benefit of orcein elastic staining of primary cutaneous melanoma specimens in detecting venous invasion. Primary cutaneous melanomas in vertical growth phase were assessed for vascular invasion. All tumour blocks were stained with haematoxylin and eosin (H&E) and orcein. The cases were reviewed by two pathologists. Vascular invasion was not identified more frequently on orcein stained slides than on H&E stained ones. Elastosis and periappendiceal elastic fibres interfered with vascular invasion detection with elastic staining. Based on our study, we conclude that elastic stains such as orcein do not improve the detection rate of venous invasion in primary cutaneous melanomas.

Retrospective health-care associated infection surveillance in oral and maxillofacial reconstructive microsurgery.

In polymorbid or anaemic patients who receive preoperative radiotherapy or undergo long duration surgery involving potentially infectious sites, perioperative antibiotic prophylaxis (PAP) that is effective against normal oral bacterial flora is mandatory and plays an important role in preventing postoperative infection. In a four-year retrospective analysis, the incidence, outcome, and the efficacy of PAP were evaluated in patients treated at the Department of Oral and Maxillofacial Surgery and Otorhinolaryngology at Kecskemét Hospital. The results were compared with data from the literature to determine if the use of PAP was adequate at the Department.During the study period (between 01/09/2007 and 31/01/2011) 108 patients were evaluated. The mean duration of prophylactic antibiotic treatment was 8.3 ± 5.2 days, with cefotaxime+metronidazole being the most commonly used combination. Surgical site infection occurred in 8 patients (7.5%) in the clean-contaminated category.Our results showed that the perioperative antibiotic prophylaxis administered at our Department was efficient and effective against the oral bacterial flora of patients. Its use is recommended in head and neck microsurgery. To avoid development of antibiotic resistance and to reduce costs, it seems that the duration of antibiotic regimen for primary surgery can be reduced from 8.3 ± 5.2 days to 3 days.

Papillary renal cell carcinoma embedded in an oncocytoma: Case report of a rare combined tumour of the kidney.

An asymptomatic 1-cm large papillary renal cell carcinoma (RCC) embedded in a 3.5-cm large oncocytoma was diagnosed and removed by right nephrectomy in a 68-year-old male investigated for the abdominal symptoms associated with cholelithiasis. The papillary RCC displayed positive immunohistochemical stainings with cytokeratin 7, alpha-methylacyl-CoA racemase and vimentin and was negative for the E-cadherin and CD117 immunostains, whereas the oncocytoma part showed opposite staining patterns. No gains of chromosomes 7 and 17 or loss of chromosome Y was detected in the papillary carcinoma by fluorescent in situ hybridization with centromeric enumeration probes. This finding is in keeping with the morphologic diagnosis of type 2 papillary RCC reported to have lower rates of these characteristic chromosomal changes. The combination of papillary RCC and oncocytoma, two tumours of different postulated origin, is extremely rare. It may represent a simple coincidence, but 2 previous cases and our current one share a few features, including the intimate embedment of the papillary RCC in the oncocytoma, the small size of the RCC and the old age of the patients. This case raises the point that renal oncocytomas can contain a hidden malignant tumour.

International multicenter tool to predict the risk of nonsentinel node metastases in breast cancer.

BACKGROUND: Axillary treatment of breast cancer patients is undergoing a paradigm shift, as completion axillary lymph node dissections (ALNDs) are being questioned in the treatment of patients with tumor-positive sentinel nodes. This study aims to develop a novel multi-institutional predictive tool to calculate patient-specific risk of residual axillary disease after tumor-positive sentinel node biopsy. METHODS: Breast cancer patients with a tumor-positive sentinel node and a completion ALND from five European centers formed the original patient series (N = 1000). Statistically significant variables predicting nonsentinel node involvement were identified in logistic regression analysis. A multivariable predictive model was developed and validated by area under the receiver operating characteristics curve (AUC), first internally in 500 additional patients and then externally in 1068 patients from other centers. All statistical tests were two-sided. RESULTS: Nine tumor- and sentinel node-specific variables were identified as statistically significant factors predicting nonsentinel node involvement in logistic regression analysis. A resulting predictive model applied to the internal validation series resulted in an AUC of 0.714 (95% confidence interval [CI] = 0.665 to 0.763). For the external validation series, the AUC was 0.719 (95% CI = 0.689 to 0.750). The model was well calibrated in the external validation series. CONCLUSIONS: We present a novel, international, multicenter, predictive tool to assess the risk of additional axillary metastases after tumor-positive sentinel node biopsy in breast cancer. The predictive model performed well in internal and external validation but needs to be further studied in each center before application to clinical use.

Petroleum jelly-induced penile paraffinoma with inguinal lymphadenitis mimicking incarcerated inguinal hernia.

Chronic granulomatous inflammation may develop after injecting foreign oily substances into the penis. The disorder affects mainly the site of administration, but regional lymphadenopathy or even systemic disease can occur. We present a 39-year-old man with petroleum jelly-induced penile lesion and unilateral inguinal lymphadenitis mimicking incarcerated inguinal hernia. At hernioplasty no hernial sac was found, but enlarged lymph nodes suspicious for malignancy were identified. The histopathologic findings of these nodes were consistent with mineral oil granuloma. Paraffinoma of the male genitalia can cause various clinical features posing a differential diagnostic dilemma. Regional lymphadenitis may be the main clinical characteristic. Patient's history, physical and histopathological examination are required to establish the diagnosis.

Limited lymph-node recovery based on lymph-node localisation is sufficient for accurate staging.

AIMS: To assess the reliability of nodal staging in colorectal carcinomas (CRCs) when only lymph nodes close to the tumour are recovered and examined histologically. METHODS: Lymph nodes from CRC resection specimens were recovered into two fractions: one from around the tumour and the 3 cm sidelong bowel segment associated with it in the proximal and distal directions, and another from the remaining part of the resection specimen. RESULTS: Of the 762 CRCs (239 right colon, 251 left colon, 257 rectum, 15 unspecified localisation) there were 393 node-negative and 369 node-positive cases. The median number of LNs examined was 18. The assessment of the LNs located in the close fraction (median 13) yielded an adequate qualitative nodal status in 756 patients (99.2%). In four cases (two rectal and two right colic), no LN metastases could be identified in the close-fraction lymph nodes, but nodes from the distant fraction contained metastases. Of the node-positive carcinomas which had at least one positive lymph node in the close fraction, 203 belonged to the pN1 category and 162 to the pN2 category of the Tumour Node Metastasis staging system. Only 14 cases (10 rectal, two right and two left colic tumours) were misclassified as pN1 (on the basis of lymph nodes recovered from the close fraction) although they were of the pN2 category. CONCLUSIONS: In general, nodal status of CRCs may be adequately assessed by examining the lymph nodes from the close fraction around the tumour and the 3 cm sidelong bowel segment in both directions.

Venous invasion demonstrated by orcein staining of colorectal carcinoma specimens is associated with the development of distant metastasis.

AIMS: To assess venous invasion (VI) and its relation to distant metastases in colorectal cancer (CRC). METHODS: Primary untreated CRC cases were assessed for VI. All tumour blocks were stained with H&E and orcein. The presence of VI and nodal status were then correlated with the presence of synchronous or metachronous distant metastases. RESULTS: VI was detected more frequently with the orcein stain (18% versus 71%). Eleven tumours (nine node-positive tumours, all VI positive) were associated with synchronous distant metastasis. During a median follow-up of 17 months nine further cases were diagnosed with distant metastasis (six node-positive tumours, all VI positive). The specificity and sensitivity of the presence of nodal metastasis for predicting distant metastasis were 0.56 and 0.75, respectively. The same values for orcein-detected VI were 0.39 and 1, respectively. CONCLUSIONS: Elastic stains such as the orcein stain enable the detection of clinically relevant VI with greater frequency than conventionally stained histological slides. If nodal involvement is an indication for systemic chemotherapy, the data presented here suggest that VI detected by the orcein stain should also be an indication for systemic chemotherapy.

[Analysis of predictive tools for further axillary involvement in patients with sentinel-lymph-node-positive, small (< or =15 mm) invasive breast cancer]. / A hónalji nyirokcsomók további érintettségére vonatkozó modellek elemzése kisméretu (< / =15 mm) ôrszemnyirokcsomó-áttétes emlôrákokban.

Small breast cancers often require different treatment than larger ones. The frequency and predictability of further nodal involvement was evaluated in patients with positive sentinel lymph nodes and breast cancers < or =15 mm by means of 8 different predictive tools. Of 506 patients with such small tumors 138 with positive sentinel nodes underwent axillary dissection and 39 of these had non-sentinel node involvement too. The Stanford nomogram and the micrometastatic nomogram were the predictive tools identifying a small group of patients with low probability of further axillary involvement that might not require completion axillary lymph node dissection. Our data also suggest that the Tenon score can separate subsets of patients with a low and a higher risk of non-sentinel node metastasis. Predictive tools based on multivariate models can help in omitting completion axillary dissection in patients with low risk of non-sentinel lymph node metastasis based on their small tumor size.

Predicting non-sentinel lymph node status after positive sentinel biopsy in breast cancer: what model performs the best in a Czech population?

Several models have previously been proposed to predict the probability of non-sentinel lymph node (NSLN) metastases after a positive sentinel lymph node (SLN) biopsy in breast cancer. The aim of this study was to assess the accuracy of two previously published nomograms (MSKCC, Stanford) and to develop an alternative model with the best predictive accuracy in a Czech population. In the basic population of 330 SLN-positive patients from the Czech Republic, the accuracy of the MSKCC and the Stanford nomograms was tested by the area under the receiver operating characteristics curve (AUC). A new model (MOU nomogram) was proposed according to the results of multivariate analysis of relevant clinicopathologic variables. The new model was validated in an independent test population from Hungary (383 patients). In the basic population, six of 27 patients with isolated tumor cells (ITC) in the SLN harbored additional NSLN metastases. The AUCs of the MSKCC and Stanford nomograms were 0.68 and 0.66, respectively; for the MOU nomogram it reached 0.76. In the test population, the AUC of the MOU nomogram was similar to that of the basic population (0.74). The presence of only ITC in SLN does not preclude further nodal involvement. Additional variables are beneficial when considering the probability of NSLN metastases. In the basic population, the previously published nomograms (MSKCC and Stanford) showed only limited accuracy. The developed MOU nomogram proved more suitable for the basic population, such as for another independent population from a mid-European country.

Heterogeneity of pT3 colorectal carcinomas according to the depth of invasion.

Colorectal carcinomas (CRCs) infiltrating through the muscularis propria layer without infiltration of adjacent structures, organs or the serosa-i.e. the pT3 tumors, compose the largest subset of large intestinal carcinomas treated by surgical resection. They are heterogeneous in terms of prognosis. CRCs treated by surgery in a period of 69 months were prospectively classified as pT3a tumors (invading to a maximum of 5 mm beyond the muscularis propria) and pT3b tumors (invading deeper). Their nodal status, incidence of vascular invasion and the presence or absence of distant metastases were analyzed in relation to the depth of invasion. Of the 593 CRCs primarily treated by surgery 429 were pT3 tumors. CRCs categorized as pT3a had significantly lower rates of nodal involvement (44% vs 75%), massive nodal involvement (pN2) (9% vs 39%), venous invasion (17% vs 30%) and distant metastasis (11% vs 28%) than pT3b tumors. Significant differences in these prognostic variables in pT3a and pT3b cancers were observed both for carcinomas of the colon and those of the rectum. Such differences were not obvious in further 66 ypT3 cases of rectal carcinoma receiving neoadjuvant treatment before surgery. Tumors in the pT3a category are associated with a better prognostic profile than pT3b tumors. This subdivision might be useful in both prognostication and treatment planning.