Mismatch repair protein expression and intratumoral budding in rectal cancer are associated with an increased pathological complete response to preoperative chemoradiotherapy: A case-control study

AIM

To determine whether the association of rectal adenocarcinoma with a defective-mismatch repair system (dMMR) was associated with a pathological complete response (pCR) to preoperative chemoradiotherapy.

METHODS

A case-control study was designed with the aim of determining if patients with rectal adenocarcinoma with dMMR had an associated high pCR rate in response to neoadjuvant chemoradiotherapy (nCRT).

RESULTS

Seventy-two cases with pCR were compared against 144 controls without pCR. Across 216 cases, the mean age was 56.8 years, 140 (64.8%) were men, and 63 (29.2%) demonstrated the dMMR system. The pCR was associated with G1 tumors, dMMR, the absence of vascular invasion, and low tumor budding in the pretreatment biopsy. In a multivariant analysis, the factors associated with pCR were dMMR (OR: 2.61; 95%CI: 1.355-5.040, P = 0.004) and a low degree of tumor budding (OR: 2.52; 95%CI: 1.366-4.894, P = 0.025).

CONCLUSION

We found an independent association between dMMR and a low rate of tumor budding, with a higher rate of pCR, in the basal biopsies of patients with rectal carcinoma subjected to nCRT.

Pre-operative Neutrophils/Lymphocyte Ratio in Rectal Cancer Patients with Preoperative Chemoradiotherapy

BACKGROUND

Several studies have reported that an elevation in neutrophils/lymphocyte ratio (NLR) is correlated with poor survival in patients with colorectal cancer, but in rectal cancer (RC), it has been reported only in a few studies. It is necessary to separate colon cancer and rectal cancer to clarify the prognostic significance of NLR, especially in patients who received chemoradiotherapy.

METHODS

It is a comparative, observational retrospective study of a cohort of 175 patients. We grouped the patients into two based on their NLR (0-3 vs. > 3) to correlate with disease-specific survival (DSS) and pathologic complete response (pCR).

RESULTS

The average NLR was 2.65 + 1.32 (range 0.58-6.89), and 144 (82.3%) patients had an NLR of 0-3. The median follow-up was 33.53 months. There were no differences in pCR between the two groups. The 5-year DSS was 78.8%. NLR did not correlate with survival. Mesorectal quality, pT3-4 tumors, lymph node metastasis, lymphovascular invasion, perineural invasion, positive margins and recurrence were statistically significant predictors of increased mortality in univariate analysis. In multivariate analysis, only overall recurrence correlated with poor survival. The analysis of the association of NLR with outcomes with different cut points (2.0, 2.5, 4 and 5) did not show differences in DSS and pCR.

CONCLUSION

In our cohort, the NLR did not serve as a prognostic marker in patients with locally advanced rectal cancer and who received chemoradiotherapy and did not correlate with pCR as well.

Tumour budding in rectal cancer. A comprehensive review

A unique and fundamental characteristic of malignant neoplastic cells is their ability to invade other tissues and metastasise. The first step in this process is the dissociation of some of these cells from the tumour invasion front, named tumour budding (TB). This phenomenon has become increasingly relevant in recent years due to its association with adverse clinicopathological characteristics and with the epithelial-mesenchymal transition. TB has been studied by mixing colon with rectal tumours, but it is clinically important to differentiate these types of tumours. A review in two databases without language restriction was performed from 1950 to 2017 about TB with an emphasis on rectal cancer. We present various aspects of TB, from its terminology and evaluation to its molecular aspects, through its clinical associations. TB is associated with adverse clinicopathological features, like lymphovascular invasion, lymph node metastasis, and decreased survival. More studies of the clinicopathological, molecular, and epidemiological characteristics of TB in rectal cancer are needed.

Extramural Perineural Invasion in pT3 and pT4 Gastric Carcinomas

BACKGROUND

Perineural invasion (PNI) is widely studied in malignant tumors, and its prognostic significance is well demonstrated. Most studies have focused on evaluating the mural PNI (mPNI); however, extramural PNI (ePNI) may influence the prognosis in gastric cancer. We evaluated the prognostic value of ePNI compared with mPNI in gastric cancer in this observational comparative cross-sectional study.

METHODS

Seventy-three pT3 and pT4 gastric carcinomas with PNI were evaluated. Forty-eight (65.7%) were in the mPNI group and the remaining in the ePNI group.

RESULTS

Clinicopathologic characteristics between the two groups were similar, except for the outcomes. The 5-year disease-specific survival (DSS) rate was 64% for the mPNI group and 50% for the ePNI group (p=.039), a difference that did not remain significant in multivariate analysis. The only independent adverse prognostic factor in multivariate analysis was the presence of lymph node metastasis (hazard ratio, 1.757; 95% confidence interval, 1.082 to 2.854; p=.023).

CONCLUSIONS

We demonstrated the prognostic effect of ePNI for DSS in surgically resected pT3-pT4 gastric cancer patients. ePNI could be considered in the staging and prognostic systems of gastric cancer to stratify patients with a high risk of recurrence.

Medullary colonic carcinoma with microsatellite instability has lower survival compared with conventional colonic adenocarcinoma with microsatellite instability

INTRODUCTION

Colorectal medullary carcinoma (MC) is a rare subtype of poorly differentiated adenocarcinoma (PDA) with unclear prognostic significance. Microsatellite instable (MSI) colorectal carcinomas have demonstrated better prognosis in clinical stage II.

AIM

To analyze the survival and clinicopathological characteristics of MCs versus PDAs with MSI in clinical stage III.

MATERIAL AND METHODS

We studied 22 cases of PDAs with MSI versus 10 MCs.

RESULTS

Of the 10 MCs, 7 patients were men; the mean age was 57.8 ±5.6 years. The mean tumor size was 9.6 ±4.1 cm, and the primary site was the right colon in 9; 7 patients showed lymph node metastases (LNM) and lymphovascular invasion (LVI). Of the 22 PDA cases, 12 (54.5%) were women with a mean age of 75 ±16.1 years. The mean tumor size was 6.4 ±3.2 cm. Twelve (54.5%) presented in the right colon, 21 (95.5%) showed LNM and 7 (31.8%) LVI. Follow-up was 32 ±8 months, with a 5-year overall survival of 42.9% for MCs and 76.6% for PDAs (p = 0.048). Univariate analysis found local recurrence (p = 0.001) and medullary subtype (p = 0.043) associated with lower survival.

CONCLUSIONS

Medullary carcinomas were of greater tumor size and associated with more LVI and worse survival versus PDAs with MSI in stage III.

Colorectal lymphoma in Mexico: clinico-pathological and survival analysis

BACKGROUND

Primary colorectal lymphomas (PCLs) are very rare. We analyze a series of PCL to establish an approximate frequency of the disease and their clinico-pathological characteristics.

METHODS

A retrospective cross-sectional study in a third-level hospital from 2006-2016. Clinico-pathologic features of 18 cases are presented.

RESULTS

PCL corresponded to 1.5% of malignant colorectal neoplasms. Ten cases presented in men, the median age was 57 years, diffuse large B-cell lymphoma (DLBCL) was the most common subtype (55.6%), 55.6% presented in cecum, 83.4% as unique polypoid tumor and the median size was 52.5 mm. The most prevalent presentation symptom was abdominal pain (61.1%). Six cases (33%) received initial surgery followed by chemotherapy, 7 cases (39%) received only chemotherapy, 2 cases received only surgery and 3 cases no-treatment. The 2-year disease specific survival was 62.7%. The only factors associated with improved survival in univariate analysis were use of surgery followed by chemotherapy (P=0.043) and HIV (P=0.043). On multivariate analysis none factor was an independent risk factor for decreased survival.

CONCLUSIONS

The improved overall survival rates in our series emphasize the importance of surgery followed systemic therapy in the treatment of this disease.

Prognostic importance of lymph node ratio after resection of ampullary carcinomas

BACKGROUND

The prognosis of the lymph node ratio (LNR) in Vater's ampulla carcinomas (VACs) is recently studied. However, there are not enough data in several populations like Latin American people. Our aim is to demonstrate the prognosis significance of the LNR in this setting.

METHODS

Pancreaticoduodenectomies for VACs were identified (n=128) from 1980 through 2015. Based on a ROC curve, a cut-off point of 0.1 was assigned for the LNR and the population was divided into two groups for comparison.

RESULTS

The LNR ≥0.1 group was statistically significant associated with recurrence (38.5% vs. 19.5%), pT3-T4 tumors (69.2% vs. 29.3%), poorly differentiated tumors (46.2% vs. 17.5%), lymphovascular invasion (61.5 vs. 17.1%), perineural invasion (38.5% vs. 19.5%), and positive margins (15.4% vs. 2.4%). In the multivariate analysis, LNR (HR 2.891; CI: 1.987-3.458, P=0.02), LNM (HR 2.945; CI: 2.478-3.245, P=0.002), perineural invasion (HR 3.327; CI: 3.172-4.156, P=0.003), and recurrence (HR 3.490; CI: 2.896-4.122, P=0.001) were associated with lower survival.

CONCLUSIONS

The LNR is a good predictor of survival and worse oncological outcomes for VACs after resection.

Overweight but not obesity is associated with decreased survival in rectal cancer

AIM OF THE STUDY

To analyse the influence of overweight and obesity in disease-specific survival (DSS) in rectal cancers at stages I-III in a population with high prevalence of overweight/obesity.

MATERIAL AND METHODS

The population (N = 304) consisted of Mexican patients with stage I-III rectal cancer during the period between 2009 and 2015. Patients were divided based on their body mass index (BMI) into normal weight 18-25 kg/m2, overweight 25-29 kg/m2, and obesity BMI > 30 kg/m2 groups. Comparison of clinicopathologic features and survival analysis were performed.

RESULTS

The median age was 58 years (interquartile range [IQR] 50-65) and the mean BMI was 26.03 ±4.06 kg/m2. Patients in the obesity and overweight groups received a lower proportion of preoperative treatment and had a higher proportion of patients in stage II. Overweight patients had a lower baseline neutrophil/lymphocyte ratio and lower survival rate than patients with normal weight and with obesity (mean survival of 69.5 months vs. 81.15 months and 86.4 months, respectively). The estimated five-year DSS was 51% for the overweight group, 81% for the normal group, and 82% for the obesity group (p = 0.026).

CONCLUSIONS

Patients with stage I-III rectal cancer in the overweight group showed a lower DSS compared to groups with normal weight and with obesity, with the last two being similar.

Does the Presence of Matted Nodes in Colon Adenocarcinoma Influence 5-Year Overall Survival?

Background and Objectives: Colon cancer (CC) is prevalent globally, constituting 11.9% of cases in Mexico. Lymph node metastases are established prognostic indicators, with extracapsular lymph node extension (ENE) playing a crucial role in modifying prognosis. While ENE is associated with adverse factors, certain aspects, like matted nodes (lymph node conglomerates), are underexplored. Matted nodes, clusters of lymph nodes infiltrated by cancer cells, are recognized as an independent prognostic factor in other cancers. This study investigates the prognostic implications of matted nodes in CC. Materials and Methods: From a retrospective analysis of 502 CC consecutive cases treated with colectomy (2005-2018), we identified 255 (50.8%) cases with lymph node metastasis (our study group), which were categorized into two groups: (1) lymph node metastasis alone (n = 208), and (2) lymph node metastasis with matted nodes (n = 47). A comparative survival analysis was performed. Results: Of the 255 patients, 38% had lymph node metastasis. Patients with matted nodes (18.4%) showed an association with higher pN stage and lymphovascular invasion. The 5-year survival rate for patients with matted nodes was 47.7%, compared to 60% without (p = 0.096); however, this association demonstrated only a statistical tendency. Multivariate analysis identified clinical stage and adjuvant chemotherapy use as independent factors contributing to survival. Conclusions: This study underscores matted nodes as potential prognostic indicators in CC, emphasizing their association with higher pN stage and reduced survival. Although the patients with matted nodes showed lower survival, this figure did not search statistical significance, but a tendency was detected, which necessitates precise further research, which is essential for validating these findings and integrating matted nodes into the broader context of colorectal cancer management.

Solid and papillary neoplasm of the pancreas (SPNP): a case report

BACKGROUND

Solid and papillary neoplasm of the pancreas (SPNP) is a rare pancreatic tumor, well known for its predilection for young women and large volume. The tumor has a favorable prognosis and differentiating it from other pancreatic tumors with aggressive behavior is necessary.

CASE DESCRIPTION

We present the case of a 34-year-old female without relevant background. She presented with abdominal pain and by fine needle biopsy was diagnosed as ductal carcinoma. During the evaluation, an abdominal ultrasound revealed a pancreatic growth that was "bulky, solid, with irregular margins, in homogeneously hypoechoic, with anechoic areas of necrosis, located lateral to the tail of the pancreas and medial to the upper pole of the left kidney and the lower splenic pole". The patient was admitted, and surgery was performed. At the laparotomy, a tumor of 15 cm in diameter was detected. The tumor was located in the tail of the pancreas, was well encapsulated, and of solid consistency. Caudal pancreatectomy with a splenectomy was carried out. The final pathology diagnosis was a SPNP.

CONCLUSIONS

In the presence of a large abdominal mass of pancreatic relevance, even in older women, the possibility of having an SPNP should always be evaluated. Given the low malignancy potential of this tumor and the excellent prognosis with radical surgical treatment, the preoperative diagnosis should always be particularly accurate. Surgical resection is recommended as the treatment of choice.

Lymph node retrieval in radical gastrectomy: the pathologist alone or the surgeon-pathologist team?

INTRODUCTION

Lymph node (LN) dissection is an important prognostic factor in gastric cancer. There is little information comparing the LN count depending on whether they are dissected in the operating room or in the pathology laboratory.

AIM

To establish if the LN count is greater in either of them.

MATERIAL AND METHODS

From 2015 to 2017 all consecutive gastrectomies with D2 dissection were prospectively evaluated based in either of 2 protocols: One started in the operating room where the surgeon separated the LN levels and then submitted the entire adipose tissue with LNs (undissected) to pathology in separate containers; the pathologist dissected the LNs from the specimens. The second protocol consisted of sending the tissue/LNs to pathology as usual (adipose tissue and LN attached to the stomach).

RESULTS

A total of 83 patients were analysed. The mean age was 58.4 years. The median number of LNs dissected in the protocol starting in the operating room was 56 (IQR: 37-74), whereas the pathology laboratory dissected a median of 39 LNs (IQR 26-53) (p = 0.005). The survival of cases dissected by both protocols were comparable (median survival of 48 and 43 months, p = 0.316).

CONCLUSIONS

The LN final count is significantly higher when LN levels are separated beforehand in the operating room compared to dissection only in pathology; however, this does not impact survival, perhaps because the number of dissected nodes in both groups is high and the quality of the surgery is good.

Report of three cases of gastric choriocarcinomas-an emphasis on morphologic changes in the non-affected gastric mucosa

Primary gastric choriocarcinomas (PGC) are very rare and aggressive neoplasms with a worrisome prognosis. Most cases are reported in Asia and presented in middle-aged adults with male predominance. Most cases are associated with an intestinal adenocarcinoma; however, the pathogenesis of this tumor is uncertain. No previous reports exist of the characteristics of the non-tumoral stomach in these patients, and this data that could help to clarify their pathogenesis. We presented a series of three cases of PGC in Latin American patients, emphasizing the characteristics of non-neoplastic mucosa.