Primary mucinous adenocarcinoma of the urethra: A clinicopathological analysis of 35 cases

AIM

Primary mucinous adenocarcinoma of the urethra represents an extremely rare entity. We sought to characterise further these tumours' clinicopathological, immunohistochemical and molecular features.

METHODS AND RESULTS

Thirty-five cases were identified, occurring in 18 males and 17 females. The mean age at diagnosis was 65 years (28-89 years). The main presentation symptoms were haematuria and urinary outlet obstruction. Microscopic analysis revealed that all 35 tumours have stromal dissection by mucin. Ten tumours showed villoglandular dysplasia, nine showed mucinous metaplasia, two showed adenocarcinoma in situ and four showed signet ring cell features. All tumours were immunopositive for CEA, while immunonegative for nuclear β-catenin; 19 of 23 (83%) expressed high molecular weight cytokeratin; 19 of 33 (58%) CK7; 28 of 34 (82%) CK20; 32 of 35 (91%) CDX2; 22 of 27 (81%) cadherin-17 (CDH-17); 26 of 29 (90%) SATB2; and one of 31 (3%) GATA3. Mismatch repair gene products, including MLH1, PMS2, MSH2 and MSH6, were immunopositive, suggesting the MSI-low genotype of mucinous adenocarcinoma of the urethra. BRAF V600E and ALK rearrangements were not detected. During the mean follow-up of 20 months, nine patients either developed distant metastasis or succumbed to the illness.

CONCLUSION

Our study, encompassing the most extensive series of 35 cases of primary mucinous adenocarcinoma of the urethra, provides crucial insights into its precise diagnosis, management and potential targeted treatments. We found a greater CDX2, SATB2 and CDH17 sensitivity in these urethral tumours for the first time, to our knowledge. We identified characteristics such as an MSI-low profile, non-V600E BRAF mutations and an absence of ALK rearrangements.

POFUT1 and PLAGL2 are characteristic markers of mucinous colorectal cancer associated with MUC2 expression

Colorectal mucinous adenocarcinoma (MAC) is one of the most lethal histological types of colorectal cancer, and its mechanism of development is not well understood. In this study, we aimed to clarify the molecular characteristics of MAC via in silico analysis using The Cancer Genome Atlas database. The expression of genes on chromosome 20q (Chr20q) was negatively associated with the expression of MUC2, which is a key molecule that can be used to distinguish between MAC and nonmucinous adenocarcinoma (NMAC). This was consistent with a significant difference in copy number alteration of Chr20q between the two histological types. We further identified 475 differentially expressed genes (DEGs) between MAC and NMAC, and some of the Chr20q genes among the DEGs are considered to be pivotal genes used to define MAC. Both in vitro and in vivo analysis showed that simultaneous knockdown of POFUT1 and PLAGL2, both of which are located on Chr20q, promoted MUC2 expression. Moreover, these genes were highly expressed in NMAC but not in MAC according to the results of immunohistological studies using human samples. In conclusion, POFUT1 and PLAGL2 are considered to be important for defining MAC, and these genes are associated with MUC2 expression.

Perirectal Mucinous Adenocarcinoma After Subtotal-Colectomy for Crohn's Disease: A Case Report

Colorectal carcinoma (CRC) represents the third most common cancer and the second highest cause of cancer-related death in the United States. CRC is particularly prevalent in patients with underlying inflammatory bowel disease. Adenocarcinoma represents more than 90% of new CRC diagnoses. The mucinous subtype of colorectal adenocarcinoma is found in approximately 10-20% of all colorectal cancer patients and is most frequently located in the proximal colon. We report a case of mucinous adenocarcinoma arising from the rectal stump of a patient who had previously undergone subtotal-colectomy with end ileostomy for Crohn's disease. She initially presented with gradually worsening chronic abdominal pain and gelatinous rectal discharge. She was found to have a complex cystic lesion communicating with her Hartman's pouch. She ultimately underwent a completion proctectomy, radical hysterectomy, and bilateral salpingo-oophorectomy in conjunction with gynecology oncology. To the best of our knowledge, this case represents the first description of a perirectal mucinous adenocarcinoma arising in a patient after subtotal-colectomy for Crohn's disease.

Radiological and clinical features of large consolidative-type pulmonary invasive mucinous adenocarcinoma

BACKGROUND

This study aimed to investigate the radiological, pathological, and prognostic characteristics of large consolidative-type pulmonary invasive mucinous adenocarcinomas (IMA).

METHODS

We retrospectively reviewed 738 patients who confirmed IMA between January 2010 and August 2022, and two radiologists reviewed imaging data to determine subtypes. We included 41 patients with pathologically large consolidative-type IMA. We analyzed their radiological, pathological, and prognostic characteristics. The recurrence-free survival (RFS) and overall survival (OS) were determined using the Kaplan-Meier method.

RESULTS

Most lesions were located in the lower lobe, with 46.3% patients showing multiple lesions. Halo, angiogram, vacuole, air bronchogram, and dead branch sign were observed in 97.6%, 73.2%, 63.4%, 61.0%, and 61.0% of the cases, respectively. Unevenly low enhancement was observed in 88.89% of patients. T3 and T4 pathological stages were observed in 50.0% and 30.6% of patients, respectively. Lymph node metastasis was observed in 16.7% patients, with no distant metastasis. Spread-through air spaces and intrapulmonary dissemination were observed in 27.8% and 19.4% patients, respectively. Moreover, Kirsten rat sarcoma viral oncogene mutations were found in 68.6% of cases, and no epidermal growth factor receptor mutations were seen. Among all mutation sites, G12V mutation is the most common, accounting for 40%. The average RFS and OS were 19.4 and 66.4 months, respectively, with 3-year RFS and OS rates of 30.0% and 75.0%, respectively. Pleural invasion and lymph node metastasis were independent risk factors for diagnosis.

CONCLUSION

Halo, vacuole, angiogram, and dead branch signs were frequently observed in consolidative-type IMA. Kirsten rat sarcoma viral oncogene mutations are common in consolidative-type IMA, especially site G12V, whereas epidermal growth factor receptor mutations were rare; therefore, gene immunotherapy was more difficult. Most patients were in stage T3-T4; however, lymph node metastasis was rare.

Mucinous Adenocarcinoma of the Prostate With Normal Prostate-Specific Antigen Levels, Pulmonary Metastasis, and the Absence of Nodal Disease: A Case Report

A 74-year-old man was suffering from nine months of perineal pain and progressive worsening of urinary symptoms including nocturia and urgency. His prostate-specific antigen (PSA) levels were 1.48 ng/mL at the time of referral. Initially, a differential diagnosis of prostatitis or seminal vesicle inflammation was made, and four weeks of antibiotics were prescribed, which were later extended to six weeks due to failure of symptoms to resolve. Magnetic resonance imaging (MRI) of the prostate was then conducted. The impression was that there was ejaculatory duct obstruction caused by enlarged seminal vesicles with no evidence of significant prostate cancer. The prostate-specific antigen density (PSAd) was 0.04, and the prostate imaging reporting and data system (PIRADS) score was I-II. A CT chest with contrast was conducted for further investigation of pulmonary nodules found on the CT urogram. It revealed multiple calcified pulmonary nodules which were suspicious of malignancy. A CT-guided biopsy of one of the pulmonary nodules was taken, and histopathological analysis revealed a mucinous adenocarcinoma. A transurethral resection of the prostate (TURP) was then performed. Histopathological analysis of the prostatic surgical specimen revealed invasive mucinous adenocarcinoma. Based on the findings, a diagnosis of mucinous adenocarcinoma of the prostate with atypical lung metastasis without osseous or regional lymph node involvement was made, stage T4 N0 M1a. The patient is currently on a treatment regimen consisting of carboplatin, pemetrexed, and pembrolizumab.

Case of lung fine needle aspiration showing mucinous cells and extracellular mucin

Mucinous neoplasm with extracellular mucin can be challenging to interpret on fine needle aspiration and core biopsies. Determining the biologic origin of the mucin/mucinous cells, that is, benign/incidental versus neoplasm, invasive versus in situ, and primary versus metastatic tumors, requires a thorough multidisciplinary evaluation. The work up of these lesions includes morphologic analysis with ancillary immunohistochemical and/or molecular studies and correlation with clinical and imaging studies. This review outlines a practical approach to the diagnosis of mucinous lesions in the lung with comprehensive review of literature.

Clinicopathological characteristics and outcomes of colorectal mucinous adenocarcinoma: a retrospective analysis from China

Background

Mucinous adenocarcinoma (MAC) is a unique subtype of colorectal cancer and its prognostic value remains controversial. This study aimed to compare the clinicopathological characteristics and prognostic differences between patients with MAC and non-mucinous adenocarcinoma (NMAC).

Methods

674 patients with NMAC, 110 patients with adenocarcinoma with mucinous component (ACWM) and 77 patients with MAC between 2016-2019 were enrolled in the study. Univariate and multivariate Cox regression were performed to analyze the factors associated with prognosis. Predictive nomograms of overall survival (OS) and cancer-specific survival (CSS) for patients with colorectal adenocarcinoma were constructed. Confounding factors were eliminated by propensity score matching (PSM).

Results

Compared with patients with NMAC, patients with MAC were more likely to have a tumor located at the proximal colon, present with a larger tumor diameter, more advanced T stage, higher frequency of metastasis, deficiency of mismatch repair, and elevated preoperative carcinoembryonic antigen. Patients with MAC were related to worse OS (HR=2.53, 95%CI 1.73-3.68, p<0.01) and CSS (HR=3.09, 95%CI 2.10-4.57, p<0.01), which persisted after PSM. Subgroup analysis demonstrated that patients with left-sided or stage III/IV MAC exhibited a comparatively worse OS and CSS than those with NMAC. Furthermore, in patients with stage II with a high-risk factor and stage III MAC, adjuvant chemotherapy was associated with an improved OS, CSS, and RFS.

Conclusion

Compared with the NMAC phenotype, the MAC phenotype was an independent risk factor for poor prognosis in colorectal adenocarcinoma with worse OS and CSS, particularly patients with left-sided colorectal cancer and stage III/IV. However, patients with MAC can still benefit from adjuvant chemotherapy.

Ureter metastasis from a primary cervical malignancy 3 years after initial treatment

Metastatic mucinous adenocarcinoma of the lower ureter is reported in a 55‐year‐old woman presenting with gross hematuria who was treated for cervical cancer 3 years prior.

Survival Benefit of Primary Tumor Resection Combined With Chemotherapy in Patients With Unresectable Colorectal Mucinous Adenocarcinoma With Liver Metastasis

OBJECTIVE

To evaluate the survival benefit of combining primary tumor resection (PTR) and chemotherapy in patients with unresectable colorectal mucinous adenocarcinoma with liver metastasis (UCR-MAC-LM).

METHODS

We obtained data from the surveillance, epidemiology, and end results database for patients with UCR-MAC-LM from 2010 to 2017. Clinicopathological characteristics were analyzed using the χ2 test. Propensity score matching was performed to balance baseline characteristics. Kaplan-Meier analysis and log-rank tests were used to estimate and compare survival outcomes. Univariate and multivariate Cox regression analyses were conducted to identify the prognostic factors.

RESULTS

A total of 10,178 patients with unresectable colorectal adenocarcinoma with liver metastasis were included, of whom 6.01% (n=612) had UCR-MAC-LM. The UCR-MAC-LM group had a higher proportion of female patients, a greater number of elderly patients, an increased incidence of right colon localization, larger tumor size, and higher T and N staging than the unresectable colorectal non-mucinous adenocarcinoma with liver metastasis group (P<0.05). Multivariate analysis identified several independent prognostic factors (P<0.05). Patients with unresectable colorectal adenocarcinoma with liver metastasis who underwent PTR+C had superior survival rates compared with those who received PTR/C alone or no treatment (cancer-specific survival, P<0.05; overall survival, P<0.05). Subgroup analysis revealed that 17 of 22 groups of patients with UCR-MAC-LM who received PTR+C had significantly prolonged long-term survival compared with those who received PTR/C alone.

CONCLUSIONS

This surveillance, epidemiology, and end results-based study indicates that PTR+C may offer a survival advantage for a specific subgroup of patients with UCR-MAC-LM compared with PTR/C alone. Nonetheless, additional clinical trials are necessary to validate these findings.

Mucinous adenocarcinoma derived from villous adenoma of the kidney with muconephrosis

Upper respiratory tract villous adenoma (VA) with muconephrosis is rare and should be included in the differential diagnosis when pelvic dilatation with a solid component is detected. VA may transform into malignant mucinous adenocarcinoma, which should be suspected if contrast enhancement on computed tomography (CT)/magnetic resonance imaging (MRI) and restricted diffusion on MRI are observed.

Development and validation of a decision tree for distinguishing pulmonary adenocarcinomas with mucinous features and metastatic colorectal adenocarcinoma

BACKGROUND

Diagnosis of mucinous carcinomas in the lung on transbronchial biopsy or fine-needle aspiration (FNA) samples can be difficult for the pathologist, because primary and metastatic tumors can have similar morphological, immunohistochemical, and molecular characteristics. Correct diagnosis is key to determine appropriate therapy and to distinguish primary from metastatic disease. This distinction often falls to the pathologist in patients with a history of mucinous adenocarcinoma of the colon. Despite its drawbacks, immunohistochemistry is often employed to help assign a primary site for mucinous adenocarcinomas in the lung. However, the published data in this regard is limited to studies that use only a handful of markers.

METHODS

The authors examined the staining characteristics and heterogeneity of CK7, TTF-1, NapsinA, CK20, CDX2, and SATB2 in resection specimens of pulmonary adenocarcinomas with mucinous features and metastatic colorectal adenocarcinoma.

RESULTS

Based on the heterogeneity, sensitivity, and specificity in this cohort, the authors developed a decision tree based on TTF-1, SATB2, CDX2, and CK7 to categorize tumors as primary or metastatic lesions. Validation of the decision tree in FNA specimens from the lungs and lung-draining lymph nodes showed 84% concurrence in cases from the lung and 100% concurrence in cases from the lymph node. In cases where the algorithm assigned a primary site, it was 95% accurate compared to the multidisciplinary diagnosis.

CONCLUSIONS

This method holds promise in distinguishing primary versus metastatic lesions in resection, biopsy, and FNA samples from the lungs.

Mucinous and Signet-Ring Cell Colonic Adenocarcinoma in Inflammatory Bowel Disease: A Case-Control Study

A higher frequency of mucinous and signet-ring cell colonic adenocarcinoma has been reported in inflammatory bowel disease (IBD). The primary aim was to investigate the frequency of mucinous and signet-ring cell colorectal adenocarcinoma in patients with IBD (Cases) versus age-matched non-IBD Controls. The secondary aims were to compare the characteristics of these two histotypes of colorectal cancer (CRC) in IBD patients vs. Controls and to search for specific risk factors in IBD. In a case-control study, all IBD patients with CRC diagnosed from 2000 to 2022 were enrolled and matched for age (1:2) with non-IBD Controls with CRC. The study population included 120 CRC patients (40 IBD, 80 Controls). In IBD, CRC included standard adenocarcinoma in 23 (57.5%) patients mucinous/signet-ring cell adenocarcinoma in 17 (42.5%) patients. The proportion of mucinous/signet-ring cell adenocarcinoma was higher in IBD than in Controls (17 [42.5%] vs. 18 [22.5%]; p = 0.03). In rectal CRC, the proportion of mucinous/signet-ring cell adenocarcinoma was higher than standard adenocarcinoma in IBD (8 [47.1%] vs. 4 [17.4%]; p = 0.04) but not in Controls (4 [22.2%] vs. 20 [32.2%]; p = 0.59). In rectal CRC, the proportion of these two histotypes was higher in Cases than in Controls (8/12 [66.6%] vs. 4/24 [16.6%]; p = 0.008), with no risk factors identified in IBD. CRC was more frequently represented by mucinous/signet-ring cell adenocarcinoma in IBD than in age-matched non-IBD Controls. In IBD, these two CRC histotypes were more frequent in the rectum.

Left testicular and pulmonary metastases of mucinous adenocarcinoma of the prostate after robot-assisted radical prostatectomy

Introduction

We present a case of mucinous adenocarcinoma of the prostate with testicular and lung metastases following robot-assisted radical prostatectomy, androgen deprivation therapy, and radiotherapy.

Case presentation

A 73-year-old man with a prostate-specific antigen level of 4.3 ng/mL was diagnosed with prostate cancer. Following the robot-assisted radical prostatectomy, the pathological diagnosis was mucinous adenocarcinoma of the prostate (pT3bpN0, Gleason score of 4 + 4). Salvage hormonal therapy and irradiation were performed after the prostatectomy. Enlargement of the left testis was noted, and 28 months after prostatectomy, computed tomography detected a left testicular tumor and nodular lesions in the bilateral lungs. The histopathological diagnosis of left high orchiectomy was metastasis of a mucinous adenocarcinoma of the prostate. Chemotherapy with docetaxel followed by cabazitaxel was initiated.

Conclusion

Mucinous prostate adenocarcinoma with distal metastases following prostatectomy has been managed for longer than 3 years with multiple treatments.

Corrigendum: Mucinous adenocarcinoma of the rectum: a whole genome sequencing study

[This corrects the article DOI: 10.3389/fonc.2020.01682.].

An Unusual Case of Mucinous Adenocarcinoma of the Lung Presenting as Septic Emboli

This is a case of a 92-year-old female with multiple hospitalizations for dyspnea on exertion and hypoxemia. Her symptoms were initially thought to be secondary to pneumonia, and on subsequent admission, culture-negative endocarditis. A computed tomography (CT) of the chest was remarkable for numerous bilateral lung nodules of varying size, some of which had a cavitary appearance raising concern for septic emboli. While a transthoracic echo was unremarkable, a transesophageal echo found a small 3 mm echodensity at the tip of the right coronary leaflet of the aortic valve and a possible mobile echodensity on the tricuspid valve leaflet. These findings further supported a clinical diagnosis of endocarditis with septic emboli in the lungs. Initial bronchoscopy yielded an unremarkable biopsy and a bronchial alveolar lavage with the growth of Actinomyces odontolyticus. During a subsequent hospitalization, a repeat bronchoscopy with transbronchial biopsy revealed a final diagnosis of invasive pulmonary mucinous adenocarcinoma. This case highlights a unique presentation of mucinous adenocarcinoma of the lung initially masquerading as septic emboli, resulting in a delay in the final diagnosis.

Primary renal mucinous adenocarcinoma masquerading as a giant renal cyst: a case report

Mucinous adenocarcinoma of the kidney is rarely reported in the literature. We present a previously unreported mucinous adenocarcinoma arising from the renal parenchyma. A 55-year-old male patient with no complaints showed a large cystic hypodense lesion in the upper left kidney on contrast-enhanced computed tomography (CT) scan. A left renal cyst was initially considered, and a partial nephrectomy (PN) was performed. During the operation, a large amount of jelly-like mucus and bean-curd-like necrotic tissue was found in the focus. The pathological diagnosis was mucinous adenocarcinoma, and further systemic examination revealed no clinical evidence of primary disease elsewhere. Then the patient underwent left radical nephrectomy (RN), and the cystic lesion was found in the renal parenchyma, while neither the collecting system nor the ureters were involved. Postoperative sequential chemotherapy and radiotherapy were administered, and no signs of disease recurrence were observed over 30 months of follow-up. Based on a literature review, we summarize the lesion with rarity and the associated dilemma in preoperative diagnosis and treatment. Given the high degree of malignancy, a careful history analysis accompanied by dynamic observation of imaging and tumor markers is recommended for the diagnosis of the disease. Comprehensive treatment based on surgery may improve its clinical outcomes.

Mucinous Adenocarcinoma of the Lung: A Great Mimicker of Pneumonia

Mucinous adenocarcinoma is a rare lung cancer that can mimic the appearance of infectious pneumonia on imaging. The present report describes the case of an 88-year-old man who presented with a cough that was not responsive to treatment. Based on chest X-ray findings consistent with pneumonia, he was treated with oral antibiotics. After the patient's symptoms did not improve, a computed tomography scan was performed, which showed a confluent consolidation in the left lower lung and a cavitation suggestive of pneumonia. The patient was then admitted to the hospital to receive intravenous antibiotics. Although his cough continued, laboratory findings were within normal ranges and bacterial cultures were negative. He underwent two bronchoscopy procedures with bronchoalveolar lavage and was diagnosed with parainfluenza and rhinovirus/enterovirus, for which he was treated with prolonged antibiotics and steroids. His symptoms still failed to improve, and a bronchoscopy with cryobiopsy was performed, with a positive result for mucinous adenocarcinoma. This case illustrates the need to distinguish mucinous adenocarcinoma from pneumonia to improve the early diagnosis of this rare cancer and patient outcomes.

Non-conventional dysplasia is frequently associated with low-grade tubuloglandular and mucinous adenocarcinomas in inflammatory bowel disease

There is limited information regarding the clinicopathological features of low-grade tubuloglandular (LGTGA) and mucinous (MAC) adenocarcinomas occurring in inflammatory bowel disease (IBD), especially with regard to their precursor lesions. METHODS AND RESULTS: Forty-six IBD colectomy specimens with LGTGA (n = 17) or MAC (n = 29) with adjacent precursor lesions were analysed. As controls, 12 IBD colectomy specimens with well- to moderately differentiated adenocarcinoma that lacked any mucinous, signet ring cell, low-grade tubuloglandular or serrated features were also analysed. Compared with MACs and controls, LGTGAs more often had a flat/invisible macroscopic appearance (LGTGAs = 88%, MACs = 34%, controls = 25%, P < 0.001). MACs were more likely to have high-grade differentiation (MACs = 31%, LGTGAs = 0%, controls = 0%, P = 0.002) and a higher pathological stage (pT3 and pT4 MACs = 76%, LGTGAs = 35%, controls = 33%, P = 0.007) than LGTGAs and controls. LGTGAs (70%) and MACs (53%) were more frequently associated with non-conventional dysplasia than controls (0%) (P < 0.001). Crypt cell (40%) and hypermucinous (34%) dysplasias were the most common non-conventional subtypes associated with LGTGAs and MACs, respectively. Synchronous dysplasia often demonstrated non-conventional features in the LGTGA (33%) and MAC (47%) groups (versus 0% for the control group, P = 0.074). Synchronous cancer frequently showed similar histological features as the main tumour (LGTGA group = 60%, MAC group = 38%, control group = 100%). CONCLUSIONS: Crypt cell and hypermucinous dysplasias are the most common precursor lesions associated with LGTGAs and MACs, respectively, and may serve as a marker of increased risk for these cancer subtypes.

Genotype-phenotype mapping of a patient-derived lung cancer organoid biobank identifies NKX2-1-defined Wnt dependency in lung adenocarcinoma

Human lung cancer is a constellation of tumors with various histological and molecular properties. To build a preclinical platform that covers this broad disease spectrum, we obtained lung cancer specimens from multiple sources, including sputum and circulating tumor cells, and generated a living biobank consisting of 43 lines of patient-derived lung cancer organoids. The organoids recapitulated the histological and molecular hallmarks of the original tumors. Phenotypic screening of niche factor dependency revealed that EGFR mutations in lung adenocarcinoma are associated with the independence from Wnt ligands. Gene engineering of alveolar organoids reveals that constitutive activation of EGFR-RAS signaling provides Wnt independence. Loss of the alveolar identity gene NKX2-1 confers Wnt dependency, regardless of EGFR signal mutation. Sensitivity to Wnt-targeting therapy can be stratified by the expression status of NKX2-1. Our results highlight the potential of phenotype-driven organoid screening and engineering for the fabrication of therapeutic strategies to combat cancer.

A distinctive cytomorphological feature of interstitial pneumonia-related lung adenocarcinoma: The potential issues and solutions in practical diagnosis

BACKGROUND

The cytological features of interstitial pneumonia (IP)-related lung adenocarcinoma (LADC) have not been clearly described. This study aimed to describe its cytomorphological features, uncover potential problems in practical cytological diagnosis, and provide possible solutions.

METHODS

Bronchial brushing cytology samples from 40 IP-related LADC cases (the IP group) and 110 control cases (LADC unrelated to IP; the non-IP group) were analyzed. All patients underwent surgery after brushing cytology, and their histopathological subtypes were determined. The authors reviewed the cytological features and focused particularly on cytoplasmic mucin production.

RESULTS

In the IP group, neoplastic cells with cytoplasmic mucin were detected at a significantly higher frequency (44.4% [8 of 18] vs. 6.3% [4 of 64]), and most of them were invasive mucinous adenocarcinomas (IMAs). Twenty-two of the 40 LADC cases in the IP group failed to be judged as "malignant/positive" (thus, they were judged to be "equivocal and/or negative"). The frequency of equivocal and/or negative judgments was 55.0% (22 of 40) in the IP group and 41.8% (46 of 110) in the non-IP group. The cytological diagnosis of IMA was difficult because it showed only slight nuclear atypia. Therefore, the authors examined the immunocytochemical expression of hepatocyte nuclear factor 4α (HNF4α), a diagnostic marker for IMA. As a result, four of the six cases that were judged to be equivocal in the IP group showed positive signals and could be retrospectively judged as malignant/positive.

CONCLUSIONS

The cytological diagnosis of IP-related LADC may be more difficult because of the larger proportion of IMA. Immunocytochemistry for HNF4α can be used to improve diagnostic confidence in IP-related LADC.

Comparison of treatment strategies for resectable locally advanced primary mucinous adenocarcinoma of the lung

BACKGROUND

Primary pure mucinous adenocarcinoma (PMA) is a rare type of lung cancer with unique clinical and prognostic features. Previous studies have shown that PMA have more early-stage cancer compared with other adenocarcinoma (ADC) subtypes. The clinicopathological features and optimal treatment strategies of resectable locally advanced mucinous adenocarcinoma lack evidence and require further study.

METHODS

In this study, we collected information from patients with stage III-N2 PMA who underwent radical surgery between 2004 and 2016 from the Surveillance, Epidemiology, and End Results (SEER) database. The clinicopathological parameters, treatments, overall survival (OS), and cancer-specific survival (CSS) were evaluated.

RESULTS

Of 242,699 eligible lung adenocarcinoma patients, 124 with PMA and 3405 with other ADCs of stage III-N2 received radical surgery were identified. Compared with other ADCs, PMA tended to appear more in the lower lobes, with higher degree of differentiation, less early T stage, and more positive lymph nodes numbers. Patients with PMA had significantly worse survival than other ADCs (OS = 45.0 vs. 57.1 months, p = 0.005, CSS = 51.8 vs. 65.5 months, p = 0.017). We explored the benefit population of postoperative radiotherapy (PORT) and found that the population with ≤7 positive lymph nodes could benefit from PORT, and OS was significantly improved (41.2 vs. 69.3 months, p = 0.034). For patients with >7 positive lymph nodes, PORT did not provide a survival benefit, while chemotherapy improved OS (10.9 vs. 23.3 months, p = 0.041). Multivariate analysis showed that race, tumor location, number of positive lymph nodes, and PORT were independent prognostic factors in patients with postoperative III-N2 lung PMA.

CONCLUSION

The prognosis of patients with resectable III-N2 primary lung PMA was significantly worse than that of other ADCs, and PORT was an independent prognostic factor. Patients with ≤7 positive lymph nodes could benefit from PORT and those with >7 positive lymph nodes could benefit from chemotherapy.

Management of Primary Female Urethral Adenocarcinoma: Two Rare Case Reports and Literature Review

Primary urethral adenocarcinoma in females is an extremely rare malignancy with unclear origin and only a few retrospective cases have been reported. The controversy continues to exist over the origin of primary urethral adenocarcinoma from periurethral glands (which include the Skene's glands), urethritis glandularis or intestinal metaplasia. Herein, we report one case of a 49-year-old female with distal urethral adenocarcinoma who presented with obstructive voiding. Abdominal and pelvic CT scans and chest radiology were unremarkable. Biopsy of the mass confirmed urethral adenocarcinoma. The patient underwent partial ureterectomy and was disease-free at the 2-years follow-up period. We also present another extremely rare case of primary urethral adenocarcinoma with mucinous features in a 58-year-old female who initially complained of external urethral orifice itching with painless urethral bleeding and was treated with local excision. The patient has not received any neoadjuvant or adjuvant therapy, and experienced tumor recurrence, inguinal lymph nodes metastasis, and even local iliopsoas metastasis during over 10-years follow-up. In conclusion, our current study emphasizes the importance of imaging studies and biopsy in making an accurate preoperative diagnosis of this rare disease, and further highlights the role of multimodal therapy. A combination of radiotherapy, chemotherapy and surgery is recommended for the optimal local and distant disease control. Moreover, better medical compliance and regular follow-up are required in these patients.

Identification of a prognostic signature and ENTR1 as a prognostic biomarker for colorectal mucinous adenocarcinoma

Background

Mucinous adenocarcinoma (MAC) is a unique clinicopathological colorectal cancer (CRC) type that has been recognized as a separate entity from non-mucinous adenocarcinoma (NMAC), with distinct clinical, pathologic, and molecular characteristics. We aimed to construct prognostic signatures and identifying candidate biomarkers for patients with MAC.

Methods

Differential expression analysis, weighted correlation network analysis (WGCNA), and least absolute shrinkage and selection operator (LASSO)-Cox regression model were used to identify hub genes and construct a prognostic signature based on RNA sequencing data from TCGA datasets. The Kaplan-Meier survival curve, gene set enrichment analysis (GSEA), cell stemness, and immune infiltration were analyzed. Biomarker expression in MAC and corresponding normal tissues from patients operated in 2020 was validated using immunohistochemistry.

Results

We constructed a prognostic signature based on ten hub genes. Patients in the high-risk group had significantly worse overall survival (OS) than patients in the low-risk group (p < 0.0001). We also found that ENTR1 was closely associated with OS (p = 0.016). ENTR1 expression was significantly positively correlated with cell stemness of MAC (p < 0.0001) and CD8+ T cell infiltration (p = 0.01), whereas it was negatively associated with stromal scores (p = 0.03). Finally, the higher expression of ENTR1 in MAC tissues than in normal tissues was validated.

Conclusion

We established the first MAC prognostic signature, and determined that ENTR1 could serve as a prognostic marker for MAC.

Prognosis of resected invasive mucinous adenocarcinoma compared with the IASLC histologic grading system for invasive nonmucinous adenocarcinoma: Surgical database study in the TKIs era in Korea

BACKGROUND

The prognosis of invasive mucinous adenocarcinoma (IMA) remains controversial and should be clarified by comparison with the International Association for the Study of Lung Cancer (IASLC) histologic grading system for invasive nonmucinous adenocarcinoma (INMA).

METHODS

This study included patients with IMA who underwent curative resection. Their clinicopathological outcomes were compared with those of patients with INMA. Propensity score matching was performed to compare the prognosis of IMA with IASLC grade 2 or 3. Kaplan-Meier survival curves and log-rank tests were used to analyze recurrence-free survival (RFS) and overall survival (OS).

RESULTS

The prognoses of IMA and IASLC grade 2 were similar in terms of RFS and OS. Although patients with IMA had better RFS than patients with IASLC grade 3, the OS was not significantly different. After propensity score matching, IMA demonstrated similar RFS to IASLC grade 2 but superior to IASLC grade 3; there was no difference in the OS compared with grades 2/3. Multivariate analysis revealed that tumor size (hazard ratio [HR] = 1.20, p = 0.028), lymphovascular invasion (HR = 127.5, p = 0.003), and maximum standardized uptake value (HR = 1.24, p = 0.005) were poor prognostic predictors for RFS. Patients with IMA demonstrated RFS similar to and significantly better than that of patients with IASLC grades 2 and 3, respectively. For OS, IMA prognosis was between that of IASLC grades 2 and 3.

CONCLUSIONS

Since the prognosis of IMA among lung adenocarcinomas appears to be relatively worse, further clinical studies investigating IMA-specific treatment and follow-up plans are necessary to draw more inferences.

Retrospective Review of Outcomes in Non-Invasive Mucinous Appendiceal Neoplasms with and without Peritoneal Spread: A Cohort Study

Patients treated surgically for local non-invasive mucinous appendiceal neoplasm (NI-MAN) may recur with the development of peritoneal dissemination (PD). The risk of recurrence and predictive factors are not well studied. Patients with NI-MAN, with or without peritoneal dissemination at presentation, were included. Patients with limited disease underwent surgical resection only. Patients with peritoneal dissemination underwent cytoreductive surgery (CRS) with or without hyperthermic intraperitoneal chemotherapy (HIPEC). Patients without PD (nPD) were compared to those who presented with PD. Thirty-nine patients were included, 25 in nPD and 14 in PD. LAMN was diagnosed in 96% and 93% of patients in nPD and PD, respectively. Acellular mucin on the peritoneal surface was seen in 16% of nPD patients vs. 50% of PD patients (p = 0.019). Two (8%) patients in the nPD group who had LAMN without wall rupture recurred, at 57 and 68 months, with a PCI of 9 and 22. The recurrence rate in the PD group was 36%. All recurred patients underwent CRS+HIPEC. A peritoneal recurrence is possible in NI-MANs confined to the appendix even with an intact wall at initial diagnosis. The peritoneal disease may occur with significant delay, which is longer than a conventional follow-up.

[CT Findings of Mucinous Adenocarcinoma Arising from the Renal Calyx in Horseshoe Kidney: A Case Report]

Mucinous adenocarcinoma of the kidney is an extremely rare cystic malignant tumor with a poor prognosis that occurs in the pelvicalyceal system. Pre-opeartive diagnosis is very difficult because the tumor's clinical and imaging features are nonspecific. Here we report a case of primary mucinous adenocarcinoma arising from the horseshoe kidney in a 69-year-old male, focusing on CT findings. The tumor was a complex cystic mass with irregular wall thickening, multifocal calcifications, and septa and progressed to pseudomyxoma peritonei postoperatively.

Correlation of Immunological and Histopathological Features with Gene Expression-Based Classifiers in Colon Cancer Patients

The purpose of this study was to evaluate the association between four distinct histopathological features: (1) tumor infiltrating lymphocytes, (2) mucinous differentiation, (3) tumor-stroma ratio, plus (4) tumor budding and two gene expression-based classifiers—(1) consensus molecular subtypes (CMS) plus (2) colorectal cancer intrinsic subtypes (CRIS). All four histopathological features were retrospectively scored on hematoxylin and eosin sections of the most invasive part of the primary tumor in 218 stage II and III colon cancer patients from two independent cohorts (AMC-AJCC-90 and AC-ICAM). RNA-based CMS and CRIS assignments were independently obtained for all patients. Contingency tables were constructed and a χ2 test was used to test for statistical significance. Odds ratios with 95% confidence intervals were calculated. The presence of tumor infiltrating lymphocytes and a mucinous phenotype (>50% mucinous surface area) were strongly correlated with CMS1 (p < 0.001 and p = 0.008) and CRIS-A (p = 0.006 and p < 0.001). The presence of mucus (≥ 10%) was associated with CMS3: mucus was present in 64.1% of all CMS3 tumors (p < 0.001). Although a clear association between tumor-stroma ratio and CMS4 was established in this study (p = 0.006), still 32 out of 61 (52.5%) CMS4 tumors were scored as stroma-low, indicating that CMS4 tumors cannot be identified solely based on stromal content. Higher budding counts were seen in CMS4 and CRIS-B tumors (p = 0.045 and p = 0.046). No other associations of the measured parameters were seen for any of the other CRIS subtypes. Our analysis revealed clear associations between histopathologic features and CMS or CRIS subtypes. However, identification of distinct molecular subtypes solely based on histopathology proved to be infeasible. Combining both molecular and morphologic features could potentially improve patient stratification.

Locally advanced rectal mucinous adenocarcinoma: is preoperative radiation necessary?

BACKGROUND

Neoadjuvant chemoradiotherapy is recommended for locally advanced rectal cancer, allowing preoperative down-staging of the primary tumor to facilitate complete surgical removal. However, further investigation is warranted for identifying whether radiotherapy is necessary for rectal mucinous adenocarcinoma (RMAC). Thus, this study was designed to explore the relationship between mFOLFOX6 with or without preoperative radiotherapy and therapeutic efficacy in locally advanced RMAC.

METHODS

A total of 81 patients were retrospectively enrolled, with MRI-defined clinical stage II/III RMAC received neoadjuvant treatment with mFOLFOX6 alone (group A) or mFOLFOX6 plus radiation (group B), followed by total mesorectal excision. Tumor down-staging and tumor response were assessed based on post-treatment MRI-defined radiographical and pathological findings. Follow-up data were retrieved, and the Kaplan-Meier curve was used to determine the relationship between the 3-year disease-free survival (DFS) and overall survival (OS) in the two groups.

RESULTS

There were no significant differences in the clinical baseline characteristics of patients between group A and group B. The sphincter preservation rate in group B was 60.9%, higher than in group A (20.0%) (P=0.031). The rate of pathological complete response (pCR) was 14.0% in group B, while no patients had pCR in group A (P=0.029), and the tumor response rate in group B was higher than in group A (52.0% vs. 16.1%, P=0.001). The 3-year probability of OS in group A and B was 77.4% and 72.0% (P=0.509), and 3-year DFS was 58.1% and 56.0% (P=0.592), respectively.

CONCLUSIONS

Neoadjuvant mFOLFOX6-based chemoradiotherapy could be a promising therapeutic option for patients with RMAC, which was associated with a high rate of pCR and sphincter preservation in comparison to treated with mFOLFOX6 alone.

Metastatic mucinous ovarian carcinoma simulating lung primary: an integrated diagnostic lesson

We herein document a rare instance of primary mucinous ovarian carcinoma metastatic to the left lung, whose deceptive secondary derivation was already envisaged according to the spectacular thromboembolism involving small pulmonary vessels, thereby realizing a centrifugal and centripetal metastatizing loop. This presentation was indicative of dismal prognosis. A multimodal biomarker key approach is herein emphasized, which included close clinico-pathologic data integration.

IgG4-related lung disease with multifocal pulmonary consolidations near the pleura: A case report

RATIONALE

Immunoglobulin G4 (IgG4)-related disease (IgG4-RD) is a systemic immune-mediated condition that can cause fibroinflammatory lesions in multiple organs. Approximately 35% of IgG4-RD patients have some symptoms in the chest and IgG4-related lung disease (IgG4-RLD) is observed in about 10% of IgG4-RD cases. In addition, it is thought that glucocorticoid therapy is effective for IgG4-RD and IgG4-RLD. It is difficult to diagnose IgG4-RLD complicated with another lung disease.

PATIENT CONCERNS

An 85-year-old Japanese man was hospitalized due to pulmonary consolidations just below the pleura in chest computed tomography while being treated with antibiotics. Previously, an upper lobectomy of the right lung was performed for an upper lung mucinous adenocarcinoma, and he was diagnosed with chronic obstructive pulmonary disease. Although he took antibiotics before admission, C-reactive protein levels were elevated.

DIAGNOSIS

IgG4 levels were also elevated (IgG4; 733 mg/dL), and lung biopsy histology showed an abundance of IgG4-positive plasma cell infiltration; about 40% of the affected area was occupied by such infiltration. Based on such findings, we finally diagnosed him as IgG4-RLD.

INTERVENTIONS

We administered 20 mg/d prednisolone.

OUTCOMES

About 2 weeks after administration of prednisolone by intravenous injection, his multifocal pulmonary consolidations just below the pleura were markedly improved and his pulmonary symptoms disappeared. Four weeks after glucocorticoid therapy, IgG4 levels decreased from 831 mg/dL (peak) to 547 mg/dL.

LESSONS

We should consider IgG4-RLD, a rare disease, when lesions are detected as pulmonary consolidations near the pleura and are unresponsive to antibiotic therapy. Glucocorticoid therapy, however, is very effective for such IgG4-RLD.

A Rare Case of Co-Existing Mucin-Producing Urothelial-Type Adenocarcinoma of the Prostate and Acinar Adenocarcinoma

Mucin-producing urothelial-type adenocarcinoma of the prostate is an extremely rare neoplasm, and its coexistence with acinar adenocarcinoma is exceptional. A 70-year-old man presented with treatment resistant symptoms of urinary obstruction. The serum prostate specific antigen (PSA) level was normal. Cystoscopy revealed a kind of "cottony fluff" in the prostatic urethra. A computed tomography (CT) scan and magnetic resonance imaging (MRI) showed a polylobulated, hyperintense lesion with mucinous content. It was located in the right lobe of the prostate and measured 35 × 27 × 35 mm. The bladder cavity did not show lesions and the gastrointestinal endoscopy was normal. Thus, the patient underwent a radical cystoprostatectomy. The histological sections showed the characteristics of a mucin-producing adenocarcinoma with extensive areas of mucin pools formation. No areas of necrosis, glandular urethritis, or carcinoma in situ were identified. Neither lymphovascular and perineural invasion nor lymph node metastases were identified. The immunohistochemical study showed diffuse positivity for keratin (KRT) 7, KRT20, and membranous beta-catenin and focal positivity for KRT34betaE12 and caudal-related homeobox gene 2 (CDX2). In addition, we identified a 10-mm focus of prostatic acinar adenocarcinoma that was positive for racemase and NKX3.1. There is no treatment algorithm for this condition; however, surgery (radical prostatectomy) with or without adjuvant chemotherapeutic treatment represents a therapeutic alternative.

Clinical significance of chromosomal integrity in gastric cancers

BACKGROUND

A whole-exome or targeted cancer genes panel by next-generation sequencing has been used widely in assisting individualized treatment decisions. Currently, multiple algorithms are developed to estimate DNA copy numbers based on sequencing data, which makes a comprehensive global glance at chromosomal integrity possible. We aim to classify gastric cancers based on chromosomal integrity to guide personalized therapy.

METHODS

We investigated copy number variations (CNV) across the entire genome of 124 gastric carcinomas via exome or targeted sequencing. Chromosomal integrity was classified as chromosomal stability (CS), chromosomal instability (CIN) and intermediate state (CIN/CS) based on CNV results. Chromosomal integrity was correlated to molecular features and clinical characteristics.

RESULTS

According the states of chromosomal integrity, gastric carcinomas can be stratified into two cohorts: CS and CIN. Our results showed a significant relationship between CIN status and TP53 mutation, but not RB1, phosphatase and tensin homolog (PTEN), or other reported DNA damage repair genes. The mutation frequency of the TP53 gene had great relevance. Our study initially revealed clinical significance of chromosomal integrity that CIN patients were prone to HER2-positive and mucinous adenocarcinoma, while CS patients were a diffuse subtype and poorly differentiated but had longer overall survival.

CONCLUSIONS

We classified gastric carcinomas into two states of chromosomal integrity with clinical implications. The dichotomy is applicable to clinical transformation. We proposed that classifying gastric cancers based on chromosomal integrity would enable us to achieve personalized therapy for patients and may be beneficial to patient stratification in future clinical trials.

Survival of Patients With UrAC and Primary BAC and Urothelial Carcinoma With Glandular Differentiation

Purpose

To investigate the significance of demographic and pathological characteristics on the survival outcomes of urachal adenocarcinoma (UrAC), primary bladder adenocarcinoma (BAC) and urothelial carcinoma with glandular differentiation (UCGD) in China.

Materials and Methods

We retrospectively analyzed cases with non-distant metastases (≤ T4M0). Of 106 patients, 30 (28.3%), 40 (37.7%), and 36 (34.0%) met the criteria for UrAC, primary BAC, and UCGD, respectively. Data on patient demographics, tumor pathology, and survival outcomes were collected. The median follow-up was 36 months. Survival was analyzed using multivariate Cox regression.

Results

Patients with UrAC were younger (51.87 ± 15.25 years) than those with primary BAC (60.50 ± 12.56 years) and UCGD (63.83 ± 11.60 years) (P<0.001). Patients with UrAC were the most likely to be stage T3–4 (70.0% vs. 40.0% vs. 44.4%; P<0.001), while the primary BAC group had a higher rate of poor differentiation than the UrAC and UCGD groups (57.4% vs. 18.5% vs. 24.1%; P<0.001). The Kaplan–Meier curves showed that the overall survival (OS), progression-free survival (PFS), and disease-specific survival (DSS) of the primary BAC group were poorer than those of both the UrAC and UCGD groups (P=0.0046,P<0.0001,P=0.0077 respectively). Regarding BAC, patients with mucinous adenocarcinoma tended to have better OS and PFS than those with other histological types (P<0.005,P=0.0245). Multivariate Cox regression analysis revealed that tumor type (P=0.002), T stage (P=0.034), and the age-adjusted Charlson Comorbidity Index (aCCI) scores (P=0.005) predicted the postoperative OS and DSS of the patients. For PFS, the tumor type (P=0.011), grade (P=0.000), and aCCI (P=0.002) scores were predictive.

Conclusion

Among UrAC, primary BAC, and UCGD patients, the prognosis was poorest for those with primary BAC. Attempts should be made to diagnose these aggressive tumors early, since patients in whom tumors are detected early appear to survive longer.

Prognosis and Sensitivity of Adjuvant Chemotherapy in Mucinous Colorectal Adenocarcinoma without Distant Metastasis

In colorectal cancer, whereas mucinous adenocarcinoma (MAC) has several poor clinical prognostic factors compared to adenocarcinoma (AC), the prognosis of MAC remains controversial. We evaluated the prognosis of MAC without distant metastasis and the effects of adjuvant chemotherapy using health insurance registry data managed by South Korea. Patients with colorectal cancer between January 2014 and December 2016 were included (AC, 22,050 [96.8%]; MAC, 729 [3.2%]). We observed no difference in overall survival (OS) between AC and MAC in stages I and II. However, MAC showed a worse OS than AC in stage III disease, especially in patients administered chemotherapy (p < 0.001). These findings persisted after propensity score matching of clinical characteristics between AC and MAC. In addition, transcriptome analysis of The Cancer Genome Atlas (TCGA) data showed increased chemoresistance-associated pathways in MAC compared to AC. In consensus molecular subtypes (CMS) classification, unlike in AC, CMSs 1, 3, and 4 comprised most of MAC and the proportions of CMSs 3 and 4 increased with stage progression. These results suggest clues to overcome resistance to chemotherapy and develop targeted treatments in MAC.

Papillary mucinous metaplasia: a distinct precursor of mucinous adenocarcinoma of the endometrium

Mucinous adenocarcinoma of the endometrium is heterogeneous, consisting of endometrioid adenocarcinoma composed of >50% mucinous cells, low-grade mucinous adenocarcinoma, microglandular adenocarcinoma, and gastric (gastrointestinal)-type adenocarcinoma. Previous studies have reported that papillary mucinous metaplasia is a possible precancerous lesion of mucinous adenocarcinoma with frequent KRAS mutations. Recently, we encountered a case of pure mucinous adenocarcinoma of the endometrium with concurrent papillary mucinous metaplasia in a 35-year-old woman. She underwent 6-month hormonal therapy for atypical endometrial hyperplasia. A follow-up biopsy led to a diagnosis of mucinous adenocarcinoma; therefore, total hysterectomy was performed. The tumor showed abundant intracytoplasmic mucin and mild-to-moderate cytologic atypia with papillary architecture. KRAS mutation analysis revealed a point mutation from GGT to GTT in codon 12. Although papillary mucinous metaplasia showed an overexpression of p16^INK4, especially in the intragrandular papillary tufts, and a low MKi67 labeling index, overt mucinous adenocarcinoma with a loss of P16^INK4a expression showed a high proliferating index of MKI67. The mass presented with stage ІA disease. During follow-up, the patient was stable and showed no recurrence. Considering the histologic similarity and incidence of KRAS mutations between papillary mucinous metaplasia and mucinous adenocarcinoma, papillary mucinous metaplasia may be a precancerous lesion for a subset of mucinous adenocarcinoma of the endometrium.

Mucin-producing urothelial-type adenocarcinoma of the prostate diagnosed after robot-assisted radical prostatectomy

INTRODUCTION

Mucin-producing adenocarcinoma of the prostate is a rare disease that includes prostate adenocarcinoma with mucus production, secondary adenocarcinoma from the bladder or colorectum, and adenocarcinoma from the urothelium of the prostatic urethra. We describe prostate-specific antigen-negative mucin-producing urothelial-type adenocarcinoma of the prostate.

CASE PRESENTATION

The patient had urinary retention and a serum prostate-specific antigen level of 0.74 ng/mL. Computed tomography and magnetic resonance imaging revealed a prostate tumor with a mucous component. We diagnosed adenocarcinoma by prostate biopsy and subsequently performed robot-assisted radical prostatectomy. Mucin-producing urothelial-type adenocarcinoma of the prostate was diagnosed by pathological examinations. Lung metastasis, developing within 3 months after surgery, was treated using chemotherapy.

CONCLUSION

Endocrine therapy is ineffective for mucin-producing urothelial-type adenocarcinoma of the prostate. Mucin-producing urothelial-type adenocarcinoma of the prostate diagnosis requires pathological and immunohistochemical analyses. It is important to surgically remove the primary lesion, and robot-assisted radical prostatectomy may provide an effective approach. Multimodal therapy is essential to treat for mucin-producing urothelial-type adenocarcinoma of the prostate.

Prognostic Analysis of Primary Breast Signet Ring Cell Carcinoma and Mucinous Breast Adenocarcinoma: A SEER Population-Based Study

Background

Primary breast signet ring cell carcinoma (SRCC) is a rare type of breast cancer with typical morphological characteristics, high aggressiveness, and poor prognosis. SRCC is different from mucinous breast adenocarcinoma (MBC). However, only a few studies have explored the clinicopathological features and prognosis of SRCC and MBC.

Methods

Data retrieved from the Surveillance, Epidemiology, and End-Results (SEER) database (2004-2015) were used to explore the prognostic effect of clinicopathological features and treatment modalities on survival outcomes of SRCC and MBC patients. Kaplan-Meier plot analysis, multivariate Cox proportional risk model, propensity score matching (PSM), and subgroup analysis were performed.

Results

A total of 167 patients with SRCC and 11,648 patients with MBC were included in the study. SRCC patients exhibited higher histological grade (p < 0.001), larger tumor volume (p < 0.001), higher rate of lymph node metastasis (p < 0.001), and higher frequency of distal metastasis (p < 0.001) compared with MBC patients. Cox proportional hazards regression analysis showed that SRCC patients had lower overall survival (OS) and breast cancer-specific survival (BCSS) compared with MBC patients. Subgroup survival analysis showed that the SRCC patients had lower OS and BCSS in subgroups including younger than 60 years old, white race, married, without chemotherapy, and received radiotherapy compared with the MBC patients in these subgroups. In addition, the SRCC patients had lower BCSS in subgroups including other races (including Asian or Pacific Islander and American Indian/Alaska Native), without surgery, and lymph node metastasis.

Conclusion

The findings showed that primary breast SRCC patients have unique clinical characteristics and worse prognosis compared with MBC patients. Notably, different treatment methods resulted in different prognosis for SRCC and MBC types; therefore, SRCC patients should be distinguished from MBC patients to improve efficacy of treatment.

Journey through Crohn's Disease Complication: From Fistula Formation to Future Therapies

Crohn’s Disease (CD) is a chronic inflammatory disorder in which up to 50% of patients develop fistula within 20 years after the initial diagnosis, and half of these patients suffer perianal fistulizing disease. The etiopathogenesis of CD-related perianal fistula is still unclear, and its phenotypical and molecular characteristics are even more indefinite. A better understanding would be crucial to develop targeted and more effective therapeutic strategies. At present, the most accredited theory for the formation of CD-related fistula identifies the epithelial-to-mesenchymal transition (EMT) as the driving force. It has been well recognized that CD carries an increased risk of malignancy, particularly mucinous adenocarcinoma is often associated with long-standing fistula in CD patients. Despite the availability of multiple treatment options, perianal fistulizing CD represents a therapeutic challenge and is associated with an important impact on patients’ quality of life. To date, the most effective management is multidisciplinary with the cooperation of gastroenterologists, surgeons, radiologists, and nutritionists and the best recommended treatment is a combination of medical and surgical approaches.

Controversies in appendiceal pathology: Mucinous and goblet cell neoplasms

Appendiceal goblet cell adenocarcinomas and mucinous neoplasms are uncommon compared with other epithelial tumours of the gastrointestinal tract. Both tumour types have been subjected to terminology that belies their biological risk and leads to confusion. Goblet cell adenocarcinomas display patchy staining for endocrine markers and, thus, were previously classified as goblet cell carcinoids. Unlike well-differentiated endocrine neoplasms, however, they often contain high-grade glandular elements and pursue an aggressive course akin to that of conventional adenocarcinoma. Although several authors have recently proposed grading schemes to predict behaviour among goblet cell neoplasms, most that contain high-grade components have already spread beyond the appendix at the time of diagnosis, whereas those confined to the appendix almost always have low-grade features; the added value of grading these tumours is limited. Contradictions also surround the nomenclature of mucinous neoplasms. The World Health Organization and others promote non-malignant terminology to describe metastatic mucinous neoplasms of the peritoneum and eliminate a benign category entirely, even though virtually all neoplasms confined to the appendix pose no recurrence risk following appendectomy. 'Low-grade appendiceal mucinous neoplasm' now encompasses a spectrum of benign tumours and malignant neoplasms in the appendix and peritoneum. Although using an umbrella term in this fashion simplifies the roles of pathologists, it provides essentially no actionable information beyond that which is already clinically apparent. Broad strokes nomenclature also ensures that many patients with no risk of recurrence will receive unnecessary surveillance while others will undergo inappropriate surgical procedures due to lapses in communication. Moreover, a surprising number of non-neoplastic mucinous lesions are misclassified as low-grade appendiceal mucinous neoplasms, which can result in unwarranted patient concern or even mismanagement. The purpose of this review is to critically evaluate the literature and describe an approach to appendiceal neoplasms that more clearly denotes their biologic risk.

Patterns and grades of presentation of colon cancer in Northern Saudi Arabia

Introduction

The primary concern related to colon cancer in Saudi Arabia is the presentation of many patients with advanced disease stages.

Aim

To determine the patterns and grades of colon cancer presentation in Northern Saudi Arabia.

Material and methods

Retrieved data and tissue blocks related to 50 colorectal patients from King Khalid Hospital, Hai'l province, Northern Saudi Arabia were used. The sample represented all available colorectal specimens (full coverage of cancer cases within 10 years). The retrieved data included a full histopathology report, gender, and age. All tissues were retrieved in the form of formalin-fixed paraffin wax processed blocks. The tissues were found to be obtained in the form of colonoscopy or/and biopsy.

Results

The diagnosed colon cancers included conventional adenocarcinoma 36 (72%), mucinous adenocarcinoma 4 (8%), carcinoma-in-situ 4 (8%), and invasive adenocarcinoma 6 (12%). Moderately differentiated and poorly differentiated stages were confirmed in 46 (92%) and 4 (8%), respectively.

Conclusions

Conventional adenocarcinoma is the most common presenting colon cancer at and relatively younger age. Mucinous adenocarcinoma is frequently presented in female patients of a somewhat more youthful generation. Most patients are diagnosed with moderately differentiated adenocarcinoma, followed by poorly differentiated adenocarcinoma. The findings necessitate the urgent intervention of national policies for early detection by implementing sustainable screening programs.

Quantitative T2 Mapping to Discriminate Mucinous from Nonmucinous Adenocarcinoma in Rectal Cancer: Comparison with Diffusion-weighted Imaging

Purpose: Mucinous adenocarcinoma (MA) is associated with worse clinicopathological characteristics and a poorer prognosis than non-MA. Moreover, MA is related to worse tumor regression grade and tumor downstaging than non-MA. This study investigated whether lesions in MA and non-MA can be quantitatively assessed by T2 mapping technique and compared with the diffusion-weighted imaging (DWI).

Methods: High-resolution MRI, DWI, and T2 mapping were performed on 81 patients diagnosed with rectal cancer via biopsy. Afterward, T2 and apparent diffusion coefficient (ADC) values were manually measured by a senior and a junior radiologist independently. By examining surgical specimens, the patients with MA and non-MA were identified. Inter-observer reproducibility was tested, and T2 and ADC values were compared using Mann–Whitney U test. Finally, receiver operating characteristic (ROC) curves were drawn to determine the cut-off value.

Results: Of the 81 patients, 11 patients with MA were confirmed by pathology. The inter-observer reproducibility of T2 and ADC values showed an excellent intraclass correlation coefficient (ICC) of 0.993 and 0.913, respectively. MA had higher T2 (87.9 ± 5.11 ms) (P = 0.000) and ADC (2.03 × 10⁻³ mm²/s) (P = 0.000) values than non-MA (66.6 ± 6.86 ms and 1.17 × 10⁻³ mm²/s, respectively). The area under the ROC curves (AUC) of the T2 and ADC values were 0.999 (95% confidence interval [CI]: 0.953–1) and 0.979 (95% CI: 0.920–0.998), respectively. When the cutoff value in T2 mapping was 80 ms, the Youden index was the largest, sensitivity was 100%, and specificity was 97%.

Conclusion: As a stable quantitative sequence, T2 mapping of MRI is useful in differentiating MA from non-MA. Compared to ADC values, T2 values are also diagnostically effective and non-inferior to ADC values.

A Rare Case of Psoas Abscess Secondary to Mucinous Adenocarcinoma of the Appendix: A Case Report

INTRODUCTION

Iliacus and psoas muscles are located in an extraperitoneal location forming the iliopsoas compartment. Iliopsoas abscess is a myositis involving this compartment. Pseudomyxoma peritonei is characterized by an abundant extracellular collection of mucin in the peritoneal cavity. When this collection is retroperitoneal, it is termed as pseudomyxoma extraperitonei. We present to you the case of a 52-year-old female with psoas abscess secondary to mucinous adenocarcinoma of the appendix, which was later diagnosed as pseudomyxoma extraperitonei.

CASE PRESENTATION

A 52-year-old female presented with pain in the right flank with discharging sinuses since one year. She had previously undergone two surgeries in the past 1 year for drainage of the abscess and had taken first line anti-tubercular treatment for around 6 months. She was managed in our institute by an open drainage of the abscess. The culture reports showed an infection with E. coli. The histopathology sections showed abundant pools of extracellular mucin with strips of columnar epithelium which indicated the pathology to be a mucinous adenocarcinoma. A contrast-enhanced computed tomography scan of the abdomen and pelvis showed a ruptured appendix mucocele and a collection in the right psoas muscle showing fistulous communication with the cecum and extending to the suture site in the right flank. Anti-tubercular treatment was stopped and an oncology opinion was taken. The patient was managed with a palliative ileostomy.

CONCLUSION

It is important to keep in mind diagnostic possibilities other than tuberculosis of the spine when managing a patient with an iliopsoas abscess. These include pathologies of the gastrointestinal and genitourinary tract, which need to be diagnosed and managed early.

Risk Factors for Recurrence of Radically Resected Mucinous Colorectal Adenocarcinoma

Background

Mucinous adenocarcinoma (MA) is a subtype of colorectal cancer (CRC) associated with a higher incidence of local extension and worse survival compared to non-mucinous adenocarcinoma, but few studies have investigated surgery-related predictors for recurrence of MA. Therefore, we aimed to elucidate the predictors for local recurrence and remote metastasis of MA after surgery.

Patients and Methods

This study retrospectively analyzed 162 patients with mucinous colorectal adenocarcinoma (MAC) after radical resection. Analysis variables included demographics, clinical indicators, pathologic stage, surgical procedure, adjuvant therapy, and recurrence. Univariate and multivariate analyses were performed to investigate the risk factors for local and distant tumor relapse.

Results

A total of 162 patients (86 male) with a mean age of 58.26 years were included; 70.37% of patients had colonic tumors, and 29.63% had rectal tumors. The 5-year disease-free survival (DFS) rates for these patients were as follows: 100% for TNM stage I, 71.2% for stage II, and 47.8% for stage III. Five-year DFS rates of MAC, colonic and rectal MA were 62.0%, 65.8%, and 51.7%, respectively. Local recurrence occurred in 38 patients and distant metastasis in 33 patients. In univariate analysis, predictors for local recurrence of MAC were intraoperative blood loss, intraoperative transfusion, and N2 stage; and predictors for distant metastasis were male sex, CA199, CEA, intraoperative blood loss, T4 stage, and N2 stage. In multivariate analysis, predictors for local recurrence of MAC were intraoperative transfusion (P=0.04, OR=4.175) and N2 stage (P=0.000, OR=5.291), and predictors for distant metastasis were male sex (P=0.049, OR=2.410), CA199 (P=0.02, OR=1.003), and T4 stage (P=0.007, OR=4.006).

Conclusion

Intraoperative transfusion and N2 stage were significant predictors for local recurrence. Male sex, CA199, and T4 stage were significant predictors for distant metastasis. Knowledge of the risk factors for postoperative recurrence provides a basis for logical approaches to treatment and follow-up of MAC.

Distinct Genomic Landscape of Colorectal Mucinous Carcinoma Determined via Comprehensive Genomic Profiling: Steps to a New Treatment Strategy

Colorectal mucinous carcinoma (MC) is associated with inferior prognosis and response to treatment compared to adenocarcinoma (AC). The molecular landscapes of MC and adenocarcinoma with mucous composition (AMC) are not well-defined. We aimed to describe the genomic landscape of MC and AMC in a large colorectal cancer cohort. Tumor samples from patients with MC, AMC, or AC were analyzed using next-generation sequencing. MC had a molecular signature distinct from that of AC; genomic features were similar between AMC and MC but not between AMC and AC. HER2 amplification and TP53 and APC mutation rates were lower, whereas SMAD4, PIK3CA, ACVR2A, KMT2D, LRP1, TGFBR2, GRIN2A, BRAF V600E, PTEN, and BRCA2 mutation rates were higher in MC than in AC. The mutation frequencies in MAPK, PI3K, and TGF- pathways were higher, whereas those of cell cycle proteins and Wnt were lower in MC and AMC than in AC. The proportion of hypermutated tumors was significantly higher in MC and AMC than in AC. As MC has a distinct molecular signature from AC, immunotherapy can be potentially applied in treating MC. Similar molecular profiles of AMC and MC suggest that treatment strategies for MC, but not AC, can be used for AMC treatment.

Peritoneal cytology as an indicator of peritoneal metastases in colorectal cancer

BACKGROUND

In the management of peritoneal metastases from colon and rectal cancer, the most favorable results are reported with an aggressive combined treatment on patients who have a small extent of the disease. A test to detect occult peritoneal metastases would greatly facilitate the management of this component of colorectal dissemination.

METHODS

Currently, the standard test by which to confirm the diagnosis of the peritoneal spread of colorectal cancer is peritoneal cytology. To study the utility of this test, we gathered information from patients with biopsy-proven peritoneal metastases. The clinical, histologic, and treatment-related features of these patients at the time of a cytoreductive surgery were statistically correlated with the results of the peritoneal cytology test.

RESULTS

Forty-nine patients with colorectal cancer peritoneal metastases and a peritoneal cytology determination at the time of a cytoreductive surgery were available for analysis. Twenty-eight patients (55.1%) had a positive test. Patients with a high peritoneal cancer index and mucinous histology were most likely to have positive peritoneal cytology.

CONCLUSION

Peritoneal cytology identified patients with mucinous histology and a large extent of disease but was consistently negative in patients who had a small extent of disease compatible with a favorable response to treatment.

Case Report

Mucinous adenocarcinoma of the thymus is a particularly rare type among thymic carcinomas. Here, we report a patient who underwent complete surgical resection of the primary mucinous adenocarcinoma of the thymus. She was 74 years old and presented with a 60-mm multilocular cystic tumor in her right anterior mediastinum. We performed extended thymo-thymectomy with partial resection of the right upper lobe and pathologically diagnosed the patient with Masaoka stage II mucinous adenocarcinoma of the thymus. Immunohistochemistry showed the absence of PD-L1, suggesting that immune check point inhibitors targeting PD-1/PD-L1 might not be effective in this case. The increased preoperative serum levels of CA19-9 decreased after the operation. CA19-9 is a biomarker for disease status. Future reports should help elucidate the pathogenesis of this disease.

Mucinous Adenocarcinoma of Gallbladder Presenting As Acute Calculous Cholecystitis

Mucinous adenocarcinoma (MAC) is a rare type of gallbladder cancer accounting for less than 5% of the reported cases. It is characterized by mucin deposition involving more than 50% of the tumor volume. It is a distinct subtype of gallbladder cancer and associated with poor prognosis. Accurate preoperative diagnosis is difficult. Most of the cases are diagnosed incidentally during the histopathological examination of the resected gallbladder. We report the case of a 75-year-old man who presented with right upper abdominal pain, fever, and vomiting for 15 days. Abdominal ultrasound revealed acute calculous cholecystitis for which he underwent laparoscopic cholecystectomy. Histological examination of the gallbladder found ulcerated gallbladder mucosa lined with dysplastic epithelium. The tumor was mainly composed of dysplastic glands floating in the pools of mucin with invasion of the perivascular connective tissue suggestive of MAC. This case highlights the importance of histological examination of gallbladder after routine cholecystectomy.

Mucinous adenocarcinoma caused by cancerization from a ciliated multinodular papilloma tumor: A case report

Ciliated multinodular papilloma tumor (CMPT), a subtype of proximal bronchiolar adenoma (BA), is a rare mucin‐producing papillary tumor arising in the peripheral lung. The nature of CMPT is so far controversial. The hypothesis that CMPT is a precancerous lesion that can lead to mucinous adenocarcinoma requires further research. A 61‐year‐old man with a ground‐glass opacity (GGO) suspected to be lung adenocarcinoma in the right lower lobe of his lung underwent surgical treatment. Postoperative pathology suggested that the patient had mucinous adenocarcinoma caused by cancerization from CMPT. Targeted next‐generation sequencing (NGS) was utilized to detect driver mutations in tumor DNA. Among the identified mutated genes, there were regrettably no high frequency mutations. This report describes a case of mucinous adenocarcinoma caused by cancerization from CMPT, indicating that CMPT may be a neoplasm rather than a metaplastic process and provides histological evidence for the hypothesis that CMPT is a precancerous lesion of mucinous adenocarcinoma.

Case Report: Mucinous Adenocarcinoma Arising From Congenital Ejaculatory Duct Cyst

Herein we present a previously unreported rare case of mucinous adenocarcinoma arising from a congenital ejaculatory duct cyst. Radiographic and endoscopic examinations revealed the tumor occurred in a cyst running through the prostate. Initially, the immunohistochemical pathology results showed that it was a metastatic mucinous adenocarcinoma, but no other primary lesions were clinically evidenced. Based on the embryonic development process of the male urogenital tract, the malformation of the patient's ejaculatory duct, and the pathological examination of the resected specimen, we considered the tumor to be a primary mucinous adenocarcinoma which originating from the hypoplastic ejaculatory duct. The tumor may have developed from the foci of intestinal metaplasia from cloacal remnants during embryonic development.