Melanoma in Mexico: Clinicopathologic Features in a Population with Predominance of Acral Lentiginous Subtype

BACKGROUND

The aim of this study was to analyze the clinicopathologic features of melanoma in México as the demographics of melanoma are not well known in Mexican and Latin American people.

MATERIALS AND METHODS

A total of 1219 patients with cutaneous melanoma were analyzed through a retrospective database collected from a cancer referral institute, and the results were compared with developed countries.

RESULTS

Median age was 57 years, and 713 (58.5 %) were females. The most common melanoma subtype was acral lentiginous melanoma (ALM), which was observed in 538 (44.1 %) patients. Median Breslow thickness was 5.2 mm. Among 837 patients with complete data, the 5-year disease-specific survival (DSS) was 52.3 %. Factors associated with worse DSS on univariate analysis were Breslow thickness (p < 0.001), recurrence (p < 0.001), ulceration (p < 0.001), positive margin (p < 0.001), ALM (p = 0.001), and male sex (p = 0.001). Multivariate analysis demonstrated Breslow thickness [hazard ratio (HR) 1.45, 95 % confidence interval (CI) 1.27-1.65; p < 0.001], positive margin (HR 1.25, 95 % CI 1.03-1.57; p = 0.018), recurrence (HR 9.56, 95 % CI 6.89-9.87; p = 0.002), ALM (HR 8.07, 95 % CI 6.77-8.95; p = 0.004), and male sex (HR 1.33, 95 % CI 1.06-1.68; p = 0.013) as independent risk factors for DSS.

CONCLUSION

Our patients had worse prognosis compared with data from the US Surveillance, Epidemiology, and End Results database. We found male sex and ALM as independent risk factors for worse survival, in addition to known risk factors.

Basal neutrophil-to-lymphocyte ratio is associated with overall survival in melanoma

Several studies have reported that a high neutrophil-to-lymphocyte ratio (NLR) is associated with poor clinical outcomes in several cancers, but this ratio has not been thoroughly studied in melanoma except in stage IV. This is the first study on NLR in melanoma stages I-III. This was a retrospective study of 742 melanoma patients. The NLR was classified into NLR<2 and a NLR≥2 on the basis of a receiver operating characteristic curve. Associations of NLR with clinicopathological characteristics and survival were examined. The median patient age was 57 years (range: 15-91; Q1=46, Q3=70), and the median Breslow's thickness was 3.0 mm (range: 0.5-60; Q1=1.0, Q3=7). Clinical stage at presentation was as follows: (i) stage I in 27%; (ii) stage II in 33.2%; (iii) stage III in 36.5%; and (iv) stage IV in 3.3%. NLR≥2 was associated with lymph node metastasis (36.6 vs. 18.1%) and recurrence (28.2 vs. 22.1%). The 5-year overall survival (OS) was 63% for the NLR<2 group and 53% for the NLR≥2 group. Stage-by-stage analysis showed that the 5-year OS in the NLR≥2 group for stages I, II, III, and IV were 91, 60, 28, and 0%, respectively, whereas for the NLR<2 group the 5-year OS were 98, 68, 31, and 0%, respectively. Significant differences between NLR<2 and ≥2 occurred only in stage II (P=0.014). Univariate analysis showed that factors associated with decreased OS clinical stage were Breslow's thickness, ulceration, male sex, and NLR≥2. In the multivariate analysis, all of these factors were predictors of decreased survival. The NLR appears to be an accurate prognostic marker for decreased OS in patients with melanoma, especially in clinical stage II. NLR≥2 correlated with lymph node metastasis and recurrence.

Mortality by age, gene and gender in carriers of pathogenic mismatch repair gene variants receiving surveillance for early cancer diagnosis and treatment: a report from the prospective Lynch syndrome database

BACKGROUND

The Prospective Lynch Syndrome Database (PLSD) collates information on carriers of pathogenic or likely pathogenic MMR variants (path_MMR) who are receiving medical follow-up, including colonoscopy surveillance, which aims to the achieve early diagnosis and treatment of cancers. Here we use the most recent PLSD cohort that is larger and has wider geographical representation than previous versions, allowing us to present mortality as an outcome, and median ages at cancer diagnoses for the first time.

METHODS

The PLSD is a prospective observational study without a control group that was designed in 2012 and updated up to October 2022. Data for 8500 carriers of path_MMR variants from 25 countries were included, providing 71,713 years of follow up. Cumulative cancer incidences at 65 years of age were combined with 10-year crude survival following cancer, to derive estimates of mortality up to 75 years of age by organ, gene, and gender.

FINDINGS

Gynaecological cancers were more frequent than colorectal cancers in path_MSH2, path_MSH6 and path_PMS2 carriers [cumulative incidence: 53.3%, 49.6% and 23.3% at 75 years, respectively]. Endometrial, colon and ovarian cancer had low mortality [8%, 13% and 15%, respectively] and prostate cancers were frequent in male path_MSH2 carriers [cumulative incidence: 39.7% at 75 years]. Pancreatic, brain, biliary tract and ureter and kidney and urinary bladder cancers were associated with high mortality [83%, 66%, 58%, 27%, and 29%, respectively]. Among path_MMR carriers undergoing colonoscopy surveillance, particularly path_MSH2 carriers, more deaths followed non-colorectal Lynch syndrome cancers than colorectal cancers.

INTERPRETATION

In path_MMR carriers undergoing colonoscopy surveillance, non-colorectal Lynch syndrome cancers were associated with more deaths than were colorectal cancers. Reducing deaths from non-colorectal cancers presents a key challenge in contemporary medical care in Lynch syndrome.

FUNDING

We acknowledge funding from the Norwegian Cancer Society, contract 194751-2017.

Colorectal cancer incidences in Lynch syndrome: a comparison of results from the prospective lynch syndrome database and the international mismatch repair consortium

OBJECTIVE

To compare colorectal cancer (CRC) incidences in carriers of pathogenic variants of the MMR genes in the PLSD and IMRC cohorts, of which only the former included mandatory colonoscopy surveillance for all participants.

METHODS

CRC incidences were calculated in an intervention group comprising a cohort of confirmed carriers of pathogenic or likely pathogenic variants in mismatch repair genes (path_MMR) followed prospectively by the Prospective Lynch Syndrome Database (PLSD). All had colonoscopy surveillance, with polypectomy when polyps were identified. Comparison was made with a retrospective cohort reported by the International Mismatch Repair Consortium (IMRC). This comprised confirmed and inferred path_MMR carriers who were first- or second-degree relatives of Lynch syndrome probands.

RESULTS

In the PLSD, 8,153 subjects had follow-up colonoscopy surveillance for a total of 67,604 years and 578 carriers had CRC diagnosed. Average cumulative incidences of CRC in path_MLH1 carriers at 70 years of age were 52% in males and 41% in females; for path_MSH2 50% and 39%; for path_MSH6 13% and 17% and for path_PMS2 11% and 8%. In contrast, in the IMRC cohort, corresponding cumulative incidences were 40% and 27%; 34% and 23%; 16% and 8% and 7% and 6%. Comparing just the European carriers in the two series gave similar findings. Numbers in the PLSD series did not allow comparisons of carriers from other continents separately. Cumulative incidences at 25 years were < 1% in all retrospective groups.

CONCLUSIONS

Prospectively observed CRC incidences (PLSD) in path_MLH1 and path_MSH2 carriers undergoing colonoscopy surveillance and polypectomy were higher than in the retrospective (IMRC) series, and were not reduced in path_MSH6 carriers. These findings were the opposite to those expected. CRC point incidence before 50 years of age was reduced in path_PMS2 carriers subjected to colonoscopy, but not significantly so.

Thyroid gland papillary carcinomas with "micropapillary pattern," a recently recognized poor prognostic finding: clinicopathologic and survival analysis of 7 cases

Micropapillary carcinoma is a histologic pattern, rather than an independent entity, that has an aggressive clinical behavior regardless of location. Histologically, it is characterized by papillary cell groups in clear spaces. The micropapillary pattern in the thyroid gland has not been studied until recently but under other names such as hobnail features or oncocytic and, therefore, is poorly understood, and reported cases are few. We report the clinicopathologic features of 7 cases obtained from a cohort of 496 papillary thyroid carcinomas, which corresponds to a prevalence of 1.4%. The proportion of the micropapillary component accounted for between 5% and 20% of the tumors, was slightly more prevalent in men, correlated with the presence of lymphovascular permeation, and, in the survival analysis, showed lower survival (even at a short follow-up, 8.5 years) than conventional carcinoma without this component (P = .001); this is consistent with poor overall survival in the short term (2-5 years) reported for carcinomas with micropapillary pattern of other locations. We believe that owing to this difference in survival (>95% of patients with conventional papillary carcinoma are alive at 8.5 years versus 42% of those having at least 5% of micropapillary pattern), the micropapillary pattern should be correctly identified and stated in the pathology report when comprising at least 5% of the tumor.

Colonic micropapillary carcinoma, a recently recognized subtype associated with histological adverse factors: clinicopathological analysis of 15 cases

AIM

Micropapillary carcinoma (MPC) is regarded as an aggressive variant of adenocarcinoma in any location. The reported proportion of a micropapillary carcinoma component in an entire tumour ranges from 5 to 95% and only one case of pure MPC has been reported. To date, approximately 130 cases of MPC in the colorectum have been reported, but it is likely that this small number is to some extent due to under-reporting because this pattern is not well recognized by the general pathologist. All previous studies have combined colonic and rectal primary tumours and most have only analysed patients with clinical Stages I or II.

METHOD

We analysed 15 cases of MPC of the colon alone, diagnosed in our institution, and compared them with 105 conventional carcinomas of the colon.

RESULTS

An MPC component was present in 10% of all colonic carcinomas. These tumours presented at a median age of 56 years, and all were of American Joint Committee on Cancer Stages III and IV. Subserosal tissue invasion was present in every case, 60% had more than four positive lymph nodes, 60% were accompanied by poorly differentiated conventional carcinoma, 40% had had an incomplete resection and a third demonstrated lymphovascular invasion. Despite these adverse prognostic factors, tumours containing MPC showed the same survival, stage by stage, as conventional adenocarcinoma in multivariate analysis, although 3-year survival (81.7%vs 87.3%, P=0.035) was worse on univariate analysis.

CONCLUSION

The histopathologist should be aware of the possibility of MPC. Three-year survival is worse than in patients with conventional colonic carcinomas in Stage III.

Synovial sarcomas of the head and neck: comparative analysis with synovial sarcoma of the extremities

OBJECTIVE

This study analyzed synovial sarcoma (SS) of the head and neck in order to identify features associated with survival improvement and compared them with the survival of SS of limbs.

METHODS

Clinical charts and histopathologic material with analysis for SYT/SSX gene rearrangement of 16 patients were reviewed. The clinicopathologic features and their association with survival were analyzed and compared with 174 SS of limbs.

RESULTS

The average age was 24.2 years (range 21-86). Eight cases occurred in each sex. The most frequent site was the parapharyngeal space (PPS). The mean tumor size was 5.38cm. Sixty-nine percent occurred in Stages II-III and 9% in Stage IV. Fifteen cases were excised: R0 resection in seven (46.7%) cases and R1 resection in eight (53.3%) cases. No patient with R0 resection has recurred, and three patients (37.5%) with R1 resection have recurred (p=0.035). Patients with R0 surgery had better survival rates compared to those who received other treatments (p=0.045). SS of head and neck showed a 5-year survival rate of 58% compared to 44.6% of the limbs (p=0.450).

CONCLUSION

The most prevalent location was the PPS. Surgical resection with clear margins correlated with low recurrence. Head and neck sarcomas had similar survival rates compared to sarcomas of limbs.

Colonic cribriform carcinoma, a morphologic pattern associated with low survival

Colorectal carcinoma is one of the most common cancers in the human body. Colorectal carcinoma is a heterogeneous disease with variegated morphological patterns; some have shown themselves to have prognostic value. The World Health Organization classification recognizes many histological variants associated with adverse prognostic factors, one is the cribriform colonic carcinoma (CCC). In this work, we analyzed 18 cases of CCC compared with 228 conventional adenocarcinomas of colon, with the hypotheses that CCC compared with non-CCC have worse prognosis and decreased overall survival. CCC represent 7.3% of all colonic adenocarcinomas in this series, it presents in a median age of 56.3 years, all cases are in clinical stage III and IV, all invade subserosal adipose tissues or serosa, 90% have >5 positive lymph nodes and 89% have lymphovascular invasion. These known adverse prognostic factors reflect a lower 5-year survival, stage by stage, than conventional intestinal-type adenocarcinoma (56.8% vs 83.3%, P = .035). Cribriform carcinoma is a morphologic pattern that is underrecognized; in this work, we demonstrate its association with low survival, extensive lymphovascular invasion, and extensive lymph node metastasis, strong indicators of aggressive disease. Their proper recognition is mandatory to increase the number of cases and series to support our findings and include it in the current classifications.

Cribriform carcinoma of the gallbladder: a clinicopathologic study of 7 cases

Carcinomas of the gallbladder are morphologically heterogeneous. Some are similar or mimic carcinomas that commonly arise in other organs and therefore can be confused with metastatic lesions. We report here the clinicopathologic features of 7 cribriform carcinomas of the gallbladder that resemble cribriform carcinomas of the breast. Five patients were women and 2 men whose ages ranged from 31 to 72 years (average age 57 y). These 7 patients were younger than those with conventional adenocarcinomas of the gallbladder (average age for males 71 y and average age for females 72 y). Five patients had cholelithiasis. The youngest patient, a 31-year-old woman, had no gallstones. Instead, she had an osteosarcoma removed from her distal femur, 4 years before. Although the osteosarcoma in this patient may be coincidental, a true association could not be entirely excluded. None of the 4 cribriform carcinomas of the gallbladder tested showed immunoreactivity for estrogen and progesterone receptors. Three patients with high nuclear grade cribriform carcinomas died as a result of the tumor which infiltrated the liver by direct extension; 3 patients with low nuclear grade cribriform carcinomas confined to the gallbladder wall survived 4 to 7 years after cholecystectomy and 1 patient was lost to follow-up. In conclusion, this study provides support to previous observations that a small proportion of gallbladder carcinomas display an unusual but predominant cribriform pattern similar to that of some invasive breast carcinomas. In contrast to mammary cribriform carcinomas, those arising in the gallbladder occur in individuals usually with gallstones, may coexist with skeletal osteosarcoma, lack estrogen and progesterone receptors, and behave aggressively like conventional adenocarcinomas of the gallbladder.

Expression of Epstein-Barr virus-encoded latent membrane protein (LMP-1), p16 and p53 proteins in nonendemic nasopharyngeal carcinoma (NPC): a clinicopathological study

BACKGROUND AND AIMS

Although the latent membrane protein type 1 (LMP1) is frequently expressed in Epstein-Barr virus (EBV) malignancies, its contribution to the pathogenesis of nasopharyngeal carcinoma (NPC) is not fully defined. LMP1 functions as a viral mimic of the TNFR family member engaging a number of signaling pathways that induce morphological and phenotypic alterations. This study aimed to investigate the LMP1 expression and EBV infection in relation to clinical outcome and survival in a series of Mexican NPC patients. We also studied expression of p16 and p53 proteins.

METHODS

We analyzed in 25 tumor specimens the expression of LMP1, p16 and p53 by immunohistochemistry (IHC) and EBV presence by IHC/in situ hybridization. Differences in clinical outcome and survival in relation to protein expression were correlated through χ(2) statistics and Kaplan-Meier survival curves.

RESULTS

Our results showed a rate of 92% (23/25) of EBV infection. The expressions of LMP-1, p16 and p53 proteins were 40.0, 44.0 and 40.0%, respectively. LMP-1 immunoexpression was more common in older patients (>50 vs. <50 years old, p = 0.02) and with parapharyngeal space invasion (p = 0.02). The presence of metastatic disease at diagnosis (p = 0.03), distant recurrence disease (p = 0.006) and shorter distance recurrence-free survival (p = 0.05) was associated with lack of p16.

CONCLUSIONS

In our series, EBV infection rates are particularly high for nonendemic NPC, although without a statistically significant difference in overall survival, LMP1 and p16 expression was correlated with poorer clinical prognosis. Probably, LMP1 and p16 detection identify a worse clinical prognosis in NPC patient subgroup.

NLRP3 activation in tumor-associated macrophages enhances lung metastasis of pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer and is highly malignant due to its late diagnosis and early metastasis. Lung metastasis of PDAC occurs in a significant number of diagnosed patients and represents high severity of disease and poor clinical outcome. However, the molecular regulation of lung metastasis of PDAC is still not fully understood. Tumor-associated macrophages (TAMs) have recently been found to play an important role in cancer initiation, proliferation, progression, and metastasis. The proliferation, differentiation, and polarization of macrophages has been shown to be regulated by interleukin 1β (IL-1β), which is generated by NLR family pyrin domain containing 3 (NLRP3)-induced formation of inflammasome. Herein we investigated whether NLRP3 plays a role in lung metastasis of PDAC through regulation of macrophage polarization.

METHODS

Gene profiles for NLRP3 (+/+) and NLRP3 (-/-) macrophages obtained from the Gene Expression Omnibus (GEO) public database were compared and analyzed for altered genes related to macrophage polarization. The regulation of macrophage polarization by NLRP3 was examined in a coculture system with naïve NLRP3 (+/+) or NLRP3 (-/-) macrophages and PDAC cells. Cell growth was analyzed by a Cell Counting Kit-8 (CCK-8) assay. Cell invasiveness and migratory potential were analyzed by transwell cell invasion assay and cell migration assay, respectively. PDAC formation and lung metastasis were analyzed in a mouse model of PDAC with and without NLRP3 knockout.

RESULTS

GEO database analysis revealed significant alteration in genes that regulate macrophage polarization in NLRP3-depleted macrophages. NLRP3-depletion in macrophages seemed to favor an M1/M2b polarization. In vitro, the presence of NLRP3 in macrophages led to M2a/c/d TAM-like polarization when they were cocultured with PDAC cells. Conversely, NLRP3 depletion in macrophages led to M1/M2b polarization when they were cocultured with PDAC cells. NLRP3-depletion significantly inhibited tumor growth and stage progression in a mouse model of PDAC and significantly reduced the occurrence of lung metastasis.

CONCLUSIONS

Our results suggested that NLRP3 activation in TAM enhanced lung metastasis of PDAC through regulation of TAM polarization.

Acral Lentiginous Melanoma: Survival Analysis of 715 Cases

INTRODUCTION:

Acral lentiginous melanoma (ALM) is an aggressive variant of melanoma; the incidence, prevalence, and prognosis differ among populations. We analyzed clinicopathological features and survival in Hispanics, a population with high ALM prevalence.

MATERIAL AND METHODS:

From 1144 patients with melanoma, we analyzed 715 ALMs and 429 non-ALMs from the National Referral Cancer Centre and compared survival.

RESULTS:

Of the ALM group, 62.8% were female; the median age was 58 years. The mean Breslow thickness was 3.56 ± 7.16 mm. ALM patients showed an estimated 5-year disease-specific survival (DSS) of 53.3%, 52.7%, and 40.8% for stage I, II, and III, respectively. For non-ALM patients, the DSS rates were 66%, 60.8%, and 48.4% for stage I, II, and III disease, respectively. Overall, the 1-, 3-, and 5-year DSS rates for patients with ALM were 85.1%, 59.4%, and 46.3%, respectively; for non-ALM patients, they were 81.3%, 64.8%, and 55.7%, respectively ( P = .168). In the multivariate analysis, factors associated with decreased DSS were high Breslow thickness, recurrence, ulceration, male sex, and advanced stage.

CONCLUSIONS:

The 1-, 3-, and 5-year DSS rates of patients with ALM were not statistically different from those of non-ALM patients. In addition to known adverse prognostic factors, male sex was also associated with worse survival.

TLE1 is expressed in the majority of primary pleuropulmonary synovial sarcomas

Pleuropulmonary synovial sarcoma (PPSS) is a rare entity, similar to synovial sarcoma of soft tissue (STSS). There are 120 published cases of PPSS, but no studies have explored the expression of TLE1. In soft tissues, it has been proven a useful marker, but in tumors of other sites, its expression has not been explored. The main objective was to study the expression and diagnostic sensitivity and specificity of TLE1 in a group of PPSS, of which the diagnosis was corroborated by fluorescence in situ hybridization confirming t(X;18) in a tissue microarray. Immunohistochemistry including TLE1, vimentin, CD99, CD56, bcl-2, AE1-AE3, EMA, CD34, CK7, CK19, calponin, and S-100 was performed on all PPSS and on 25 control cases (five carcinomas, ten mesotheliomas, and ten thoracic sarcomas). TLE1 was positive in 11 cases (73.3%); bcl-2 and vimentin in 100%; calponin and CD56 in 26.6%; CD99, CK AE1-AE3, CK19, CK7, and EMA in 80%; and S100 negative in all. The only biphasic PPSS was positive for epithelial markers only in the epithelial component. TLE1 was negative in all control cases. TLE1 is expressed in 73% of PPSS, a value inferior to that reported in STSS, but is highly specific for PPSS. TLE1 may therefore be of value in the differential diagnosis of PPSS, but should be used in a panel of antibodies.

Prognosis of Signet Ring Cell Carcinoma of the Colon and Rectum and their Distinction of Mucinous Adenocarcinoma with Signet Ring Cells. A Comparative Study

Signet ring cell carcinoma (SRCC) of the colorectum is very rare, comprising between <1% and 2.4% cases of colorectal cancer. Patients' prognoses are poor. Several case reports had described as SRCC cases that are mucinous adenocarcinomas (MAC) with signet ring cells (SRC). In order to clearly delineate between MAC with SRC and SRCC, we performed a retrospective study at a national cancer referral center in which survival and clinicopathological characteristics between these two forms were compared and also SRCC were characterized by immunohistochemistry. We retrieved 32 cases that had been classified as either SRCC or MAC with SRC subtypes. It was noted that SRCC patients presented at older ages, demonstrated more advanced clinical stages, lymphovascular invasion, lymph node metastases, and higher carcinoembrionic levels than MAC with SRC patients. Regarding SRCC immunophenotype, 50% showed loss of CDX2 expression, 33% were CK20 negative, 41.7% were CK7 positive, and 25% were negative for both CK7 and CK20. For the MAC with SRC and SRCC groups, the median disease-specific survival (DSS) was 46.1 months (95% CI 36.9-55.25) and 22.4 months (95% CI 5.1-39.7 [p = 0.039]), respectively. The 3-year DSS was 80.7% and 28.6% (p = 0.017) for the MAC and SRCC patients, respectively. Univariate and multivariate analyses showed that SRCC was associated with decreased survival. SRCC had several clinicopathological features that permitted differentiation of MAC with SRC from SRCC patients, who had a poor DSS. A differential diagnosis for metastatic gastric cancer is only possible with a good clinicopathological correlation.

Mesorectal pathologic assessment in two grades predicts accurately recurrence, positive circumferential margin, and correlates with survival

BACKGROUND AND OBJECTIVES

We aimed to determine the prognostic value of the mesorectum quality assessed in a two-grade system compared with a classic system.

METHODS

Consecutive patients undergoing surgery for rectal cancer were included (n = 103). Mesorectum was assessed into three grades (classic system: complete, nearly complete, incomplete) and compared with a two-grade system (adequate, inadequate).

RESULTS

Mesorectum was complete in 62 (60.25%) patients, nearly complete in 21, and incomplete in 20. Reassessment showed adequate mesorectum in 83 (80.5%) patients and inadequate in 20. A R0 resection was achieved in 90.4% of adequate mesorectum and in 65% of inadequate mesorectum (P = 0.006). Recurrence was present in 18% of adequate mesorectum patients as compared with 50% of inadequate mesorectum (P = 0.003). The classic system failed to accurately predict the 5-year survival rate between complete (78.9%) and nearly complete (86.2%) categories (P = 0.235); whereas a two grading system showed a 5-year survival rate of 80.8% for adequate versus 39.3% for inadequate (P = 0.034).

CONCLUSION

High recurrence occurred in inadecuate mesorectum patients and was correlated with R1/R2 resections, positive margins, and decreased survival. We propose a simplified classification of mesorectum that correlates with survival and overall recurrence.

From colorectal cancer pattern to the characterization of individuals at risk: Picture for genetic research in Latin America

Colorectal cancer (CRC) is one of the most common cancers in Latin America and the Caribbean, with the highest rates reported for Uruguay, Brazil and Argentina. We provide a global snapshot of the CRC patterns, how screening is performed, and compared/contrasted to the genetic profile of Lynch syndrome (LS) in the region. From the literature, we find that only nine (20%) of the Latin America and the Caribbean countries have developed guidelines for early detection of CRC, and also with a low adherence. We describe a genetic profile of LS, including a total of 2,685 suspected families, where confirmed LS ranged from 8% in Uruguay and Argentina to 60% in Peru. Among confirmed LS, path_MLH1 variants were most commonly identified in Peru (82%), Mexico (80%), Chile (60%), and path_MSH2/EPCAM variants were most frequently identified in Colombia (80%) and Argentina (47%). Path_MSH6 and path_PMS2 variants were less common, but they showed important presence in Brazil (15%) and Chile (10%), respectively. Important differences exist at identifying LS families in Latin American countries, where the spectrum of path_MLH1 and path_MSH2 variants are those most frequently identified. Our findings have an impact on the evaluation of the patients and their relatives at risk for LS, derived from the gene affected. Although the awareness of hereditary cancer and genetic testing has improved in the last decade, it is remains deficient, with 39%-80% of the families not being identified for LS among those who actually met both the clinical criteria for LS and showed MMR deficiency.

Endometrial stromal sarcomas: immunoprofile with emphasis on HMB45 reactivity

OBJECTIVES

We describe the morphologic and immunohistochemical features of 17 endometrial stromal neoplasms, 16 sarcomas, and one stromal nodule.

METHODS

We reviewed 35 cases interpreted as endometrial stromal neoplasms, but 17 high-grade endometrial stromal sarcomas (ESS) and one case of mixed endometrial sarcoma and leiomyosarcoma were excluded from the study. Data from the Surveillance Epidemiology and End Results program on low- and high-grade ESS for 1973 through 2003 were obtained.

RESULTS

One uterine primary ESS had collections of clear cells (20%), while a metastatic ESS contained predominantly clear cells (90%). CD10 (88.2%) and smooth muscle actin (70.5%) were the most common positive immunohistochemical markers. The latter marker was located in the cytoplasm in 47% of the ESS and in the nucleus in 23.5%, a previously unreported feature. HMB45 was detected in 23.5% of the ESS, which contrasts with the 2% reported by other authors.

CONCLUSIONS

The presence of clear cells and HMB45 reactivity does not justify the term perivascular epithelioid cell tumors for these neoplasms. Two of 17 patients with ESS died of metastatic disease. However, among 274 cases of ESS (all stages included) collected by the Surveillance Epidemiology and End Results Program of the National Cancer Institute during a 30-year period, the 10-year survival rate was 94%.

Effect of the COVID-19 pandemic on surgery for indeterminate thyroid nodules (THYCOVID): a retrospective, international, multicentre, cross-sectional study

BACKGROUND

Since its outbreak in early 2020, the COVID-19 pandemic has diverted resources from non-urgent and elective procedures, leading to diagnosis and treatment delays, with an increased number of neoplasms at advanced stages worldwide. The aims of this study were to quantify the reduction in surgical activity for indeterminate thyroid nodules during the COVID-19 pandemic; and to evaluate whether delays in surgery led to an increased occurrence of aggressive tumours.

METHODS

In this retrospective, international, cross-sectional study, centres were invited to participate in June 22, 2022; each centre joining the study was asked to provide data from medical records on all surgical thyroidectomies consecutively performed from Jan 1, 2019, to Dec 31, 2021. Patients with indeterminate thyroid nodules were divided into three groups according to when they underwent surgery: from Jan 1, 2019, to Feb 29, 2020 (global prepandemic phase), from March 1, 2020, to May 31, 2021 (pandemic escalation phase), and from June 1 to Dec 31, 2021 (pandemic decrease phase). The main outcomes were, for each phase, the number of surgeries for indeterminate thyroid nodules, and in patients with a postoperative diagnosis of thyroid cancers, the occurrence of tumours larger than 10 mm, extrathyroidal extension, lymph node metastases, vascular invasion, distant metastases, and tumours at high risk of structural disease recurrence. Univariate analysis was used to compare the probability of aggressive thyroid features between the first and third study phases. The study was registered on ClinicalTrials.gov, NCT05178186.

FINDINGS

Data from 157 centres (n=49 countries) on 87 467 patients who underwent surgery for benign and malignant thyroid disease were collected, of whom 22 974 patients (18 052 [78·6%] female patients and 4922 [21·4%] male patients) received surgery for indeterminate thyroid nodules. We observed a significant reduction in surgery for indeterminate thyroid nodules during the pandemic escalation phase (median monthly surgeries per centre, 1·4 [IQR 0·6-3·4]) compared with the prepandemic phase (2·0 [0·9-3·7]; p<0·0001) and pandemic decrease phase (2·3 [1·0-5·0]; p<0·0001). Compared with the prepandemic phase, in the pandemic decrease phase we observed an increased occurrence of thyroid tumours larger than 10 mm (2554 [69·0%] of 3704 vs 1515 [71·5%] of 2119; OR 1·1 [95% CI 1·0-1·3]; p=0·042), lymph node metastases (343 [9·3%] vs 264 [12·5%]; OR 1·4 [1·2-1·7]; p=0·0001), and tumours at high risk of structural disease recurrence (203 [5·7%] of 3584 vs 155 [7·7%] of 2006; OR 1·4 [1·1-1·7]; p=0·0039).

INTERPRETATION

Our study suggests that the reduction in surgical activity for indeterminate thyroid nodules during the COVID-19 pandemic period could have led to an increased occurrence of aggressive thyroid tumours. However, other compelling hypotheses, including increased selection of patients with aggressive malignancies during this period, should be considered. We suggest that surgery for indeterminate thyroid nodules should no longer be postponed even in future instances of pandemic escalation.

FUNDING

None.

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.

Mixed gastric carcinoma with intestinal and cribriform patterns: a distinctive pathologic appearance associated with poor prognosis in advanced stages and a potential mimicker of metastatic breast carcinoma

Gastric adenocarcinoma is characterized by marked heterogeneity at cytological and architectural level and frequently shows overlap between microscopic patterns. This article describes a peculiar pattern of gastric adenocarcinoma, previously unreported, that combines intestinal type adenocarcinoma with areas of cribriform pattern that resembles both architectural and cytological in situ ductal carcinoma of the breast and to the best of the authors' knowledge, there are no earlier reports of this pattern in the stomach, which has been named "gastric carcinoma with cribriform component (CGA). The authors analyzed 12 cases of intestinal type adenocarcinoma with areas at least 20% of cribriform pattern (range from 20% to 90%) that was present in 9% of intestinal type gastric adenocarcinomas in their institution. There is slight predilection for male sex, and the median age of presentation is 55.8 years. The phenotype by immunohistochemistry is the same as with conventional (non-CGA) carcinomas. CGA shows more frequent lymphovascular invasion (P = .039), perineural invasion (P = .027) and resembles both in situ and invasive cribriform carcinoma of the breast. In clinical stage III the overall 3-year survival of CGA was worse than those with non-CGA component (38.6% vs 25%; 3-year survival, P = .010) and proves to be an independent adverse factor for overall survival in a multivariate analysis. Compared with conventional gastric carcinomas, CGA is deep infiltrating, has more nodal metastases, more lymphovascular and perineural invasion, and has decreased overall survival. Thus, proper recognition and report is important, even in small biopsies or small foci.

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.

Stage I-III colon cancer patients with tumor deposits behave similarly to stage IV patients. Cross-section analysis of 392 patients

BACKGROUND AND OBJECTIVES

Tumor deposits (TDs) are associated with adverse prognostic factors and decreased survival in colorectal cancer. However, controversy exists regarding their definition, evaluation, and staging categories. This study aimed to determine the survival and recurrence impact of the TD in colon adenocarcinomas; and to determine if TD patients behave similarly to stage IV patients.

METHODS

Cross-section study from 392 patients with colon adenocarcinoma from 2005 to 2012. We performed survival analysis and further stratified patients considering TD patients as a "stage IV-TD" to demonstrate if they behave similarly than stage IV patients.

RESULTS

From 392 patients, 204 (52%) were men, the mean age was 57.4 ± 13.9 years and 11.5% of cases had TD. In a multivariate analysis, TD failed to predict mortality and recurrence. Considering cases with TD as stage IV-TD, their mean survival was similar to stage IV patients (69.3 and 64.6 months, respectively) and different to those in stage III (110.5 months), II (135.7 months), and I (114.9 months) (P < 0.001).

CONCLUSIONS

TD failed to predict mortality and recurrence. Patients with TD in stage I-III shows similar mortality than stage IV patients; then, we suggest putting them into a substage IV category instead of the N1c category.

A snapshot of current genetic testing practice in Lynch syndrome: The results of a representative survey of 33 Latin American existing centres/registries

We aimed to assess the current genetics practice to manage patients with Lynch syndrome (LS) across Latin America. A Latin American LS survey was sent out to 52 centres/registries, comprising a total of 12 countries from the region. Overall, 33 centres completed the survey, of which the oldest LS registry was established in 1992 in Sao Paulo (Brazil), and the youngest this year in San Jose (Costa Rica). In total, 87% (26/30) of the participating centres/registries belonging to the nine countries are performing genetic testing. Overall, 1352 suspected families were sequenced. Pathogenic variants were identified in 34% of the families, with slightly differing distribution of variants between females and males. Path_MLH1 variants were identified in 39% of females and 50% of males (p = 0.023), while path_MSH2 were identified in 37% of females and males, followed by path_PMS2 in 11% of females and 8% of males, path_MSH6 in 13% of females and 3% of males (p < 0.001) and path_EPCAM in 0.3% of females and 2% of males. In Latin America, 9 of 12 (75%) participating countries had implemented healthcare for LS. LS screening is inconsistently applied within Latin America healthcare systems because of structural differences in the healthcare systems between the countries.

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.