Intestinal type of lung adenocarcinoma in younger adults

Pulmonary enteric adenocarcinoma: a literature review

Pulmonary enteric adenocarcinoma (PEAC) is an extremely rare type of non-small cell lung cancer (NSCLC) with a histologic pattern that mimics metastatic colorectal cancer (MCC). The main clinical symptoms in PEAC patients are dyspnoea, coughing, hemoptysis, and chest and back pain. The first article about PEAC appeared in 1991 in the form of a case report. As a variant of invasive lung carcinoma, only a small number of case reports and clinical research studies have been carried out, and the only one guidance on diagnosis and treatment is the WHO Tumor Classification book. It is important for doctors to distinguish PEAC from MCC to extend survival time and improve the quality of life. We reviewed the existing literature regarding the diagnosis, treatment, and prognosis of PEAC to provide some valuable clinical references.

Pulmonary enteric adenocarcinoma: an overview

Most commonly described as sporadic, pulmonary adenocarcinoma with enteric differentiation (PAED) is a rare variant of invasive lung cancer recently established and recognised by the World Health Organization. This tumour is highly heterogeneous and shares several morphological features with pulmonary and colorectal adenocarcinomas. Our objective is to summarise current research on PAED, focusing on its immunohistochemical and molecular features as potential tools for differential diagnosis from colorectal cancer, as well as prognosis definition and therapeutic choice. PAED exhibits an 'entero-like' pathological morphology in more than half cases, expressing at least one of the typical immunohistochemical markers of enteric differentiation, namely CDX2, CK20 or MUC2. For this reason, this malignancy appears often indistinguishable from a colorectal cancer metastasis, making the differential diagnosis laborious. Although standard diagnostic criteria have not been established yet, in the past few years, a number of approaches have been addressed, aimed at defining specific immunohistochemical and molecular signatures. Based on previously published literature, we have collected and analysed molecular and immunohistochemical data on this rare neoplasm, and have described the state of the art on diagnostic criteria as well as major clinical and therapeutic implications.The analysis of data from 295 patients from 58 published articles allowed us to identify the most represented immunohistochemical and molecular markers, as well as major differences between Asian PAEDs and those diagnosed in European/North American countries. The innovative molecular approaches, exploring driver mutations or new gene alterations, could help to identify rare prognostic factors and guide future tailored therapeutic approaches to this rare neoplasm.

Differential diagnosis of pulmonary enteric adenocarcinoma and metastatic colorectal carcinoma with the assistance of next-generation sequencing and immunohistochemistry

PURPOSE

Pulmonary enteric adenocarcinoma (PEAC), defined as tumors with an enteric component exceeding 50% and a histological morphology similar to colorectal cancer (CRC) and metastatic colorectal carcinoma (MCC), is an extremely rare primary lung adenocarcinoma, which was recently recognized by World Health Organization (WHO). Adenocarcinomas with intestinal differentiation have also been described in other anatomic sites, including paranasal sinuses, extrahepatic biliary tree, uterine and cervix, ovary. The morphologic spectrum and immunohistochemical profiles of PEAC overlap with those of colonic adenocarcinomas, the diagnosis of PEAC remains challenging. Currently, colonoscopy has to be performed to confirm the diagnosis, resulting in low compliance due to its invasiveness. Due to the rareness of PEAC, its molecular signature has not been comprehensively examined.

METHODS

In this study, we investigated the molecular signatures associated with PEAC and its histological counterparts, CRC and MCC using capture-based targeted sequencing.

RESULTS

We revealed that 12/13 (92.31%) PEAC patients harbored mutations in well-established driver genes for non-small cell lung cancer and none of them had mutations unique to CRC. Furthermore, 13/15 (86.7%) of MCC harbored mutations that are frequently seen in CRC.

CONCLUSION

Collectively, our study showed that PEAC, exhibiting a similar mutational profile with NSCLC, showed a distinctive signature from CRC and MCC. Furthermore, we derived a classification model, intergrading both IHC markers and genetic signature, to accurately diagnose PEAC.

Distinctive features of immunostaining and mutational load in primary pulmonary enteric adenocarcinoma: implications for differential diagnosis and immunotherapy

Background

Primary pulmonary enteric adenocarcinoma (PEAC) is an extremely rare variant of invasive lung cancer. It is highly heterogeneous while shares some common morphologic and immunohistochemical features with usual pulmonary adenocarcinoma (PAC) and colorectal adenocarcinoma (CRAC), making the differential diagnosis difficult. At present there are only limited studies about distinctive features of primary PEAC and the results are often inconsistent.

Methods

We retrospectively analyzed total 129 primary PEACs and 50 CRACs that were published since 1991 or diagnosed in our centre. Among them eight typical samples of primary PEACs and usual PACs were detected by targeted exome sequencing.

Results

The combination of CK7⁺/CDX2⁺ acquires high sensitivity (71.3%) and specificity (82%) in differential diagnosis of PEACs from CRAC. The primary PEACs harbor a high incidence of KRAS mutation but almost absent of EGFR mutation. Moreover, compared with usual PACs, the primary PEACs have higher nonsynonymous tumor mutation burden and more frequent MMR mutation.

Conclusions

The combination of CK7⁺/CDX2⁺ immunostaining and the distinctive genetic signatures, including low incidence of sensitivity genes mutations and high tumor mutation burden, is an important supplementary to the clinical differential diagnosis of primary PEACs. Our findings thus have significant implications for development of individualized treatment strategy in these patients.

Genetic mutations in lung enteric adenocarcinoma identified using next-generation sequencing

Primary lung enteric adenocarcinoma is a rare type of invasive lung carcinoma. Its morphological and immunohistochemical characteristics are similar to those of metastatic colorectal carcinoma, but there is no associated primary colorectal carcinoma. The purpose of this study is to identify mutations by assessing the genetic profile of lung enteric adenocarcinoma with next-generation sequencing (NGS). This study included 11 lung enteric adenocarcinoma patients (5 males and 6 females) from three different centers who received treatment between Feb 2013 and Dec 2016. Immunohistochemical analysis failed to reveal any markers that differentiated this carcinoma from primary gastrointestinal adenocarcinoma. NGS analysis identified ALK/ROS1 primary point mutations in 5 patients (71.42%, 5/7) and MSH2/MSH6 point mutations in 3 patients (42.86%, 3/7). There was no case with drive genes changed, such as EGFR mutation, ALK rearrangement, ROS1 rearrangement, RET rearrangement, MET amplification or 14 exon skipping mutation. The median overall survival of the 11 lung enteric adenocarcinoma patients was 9.0 months. Further, subgroup analysis showed that the median OS of patients with ALK/ROS1 primary point mutations was 6.5 months and that of patients with MSH2/MSH6 primary point mutations was 26.0 months. These two mutations were the most frequent features, but this carcinoma generally showed genetic heterogeneity. Even though we have revealed some hitherto unidentified genetic mutations associated with lung enteric adenocarcinoma, the findings are preliminary and further investigations on more patients will be required to validate our findings.

Clinicopathological, radiographic, and oncogenic features of primary pulmonary enteric adenocarcinoma in comparison with invasive adenocarcinoma in resection specimens

Primary pulmonary enteric adenocarcinoma (PEAC) is a rare subtype of primary lung adenocarcinoma. However, it is not known whether there are any distinctive clinical or molecular features.PEACs were retrospectively identified in 28 patients from July 2014 to June 2016. We compared the clinicopathological, radiographic, and oncogenic characteristics of PEAC and primary pulmonary invasive adenocarcinoma (IAC).A total of 28 PEAC patients and 92 IAC patients were compared. PEAC occurred more frequently in males (P = .008), in older patients (P = .041), in those with larger lesions (P = .001), and in those in a more advanced stage (P = .011). Radiologically, PEAC patients had larger lesions (P = .025) and more solid (P = .006); however, there were no statistically significant differences in lobulation, spiculation, pleural indentation, pleural effusion, and lymphadenopathy between PEAC and IAC. PEAC had higher values of carcinoembryonic antigen (P = .008) and carbohydrate antigen 19-9 (P < .001) than IAC. PEAC had a higher incidence (40% vs 63%, P < .001) of Kristen rat sarcoma viral oncogene homolog (KRAS) mutations and a lower incidence (10.71% vs 3.3%, P < .001) of epidermal growth factor receptor (EGFR) mutations. Villin may be a useful marker in the differential diagnosis of PEAC. KRAS mutations occurred more frequently in PEACs, which are cytokeratin 7-negative (P = .032). EGFR mutation rates were higher in PEACs, which are cytokeratin 20- and caudal type homeobox transcription factor 2-negative (P = .041).PEAC is a rare and heterogeneous nonsmall-cell lung cancer subgroup with distinctive clinicopathological, radiographic, and molecular features. These results need to be further confirmed in future studies.

Combination of cadherin-17 and SATB homeobox 2 serves as potential optimal makers for the differential diagnosis of pulmonary enteric adenocarcinoma and metastatic colorectal adenocarcinoma

Background

Pulmonary enteric adenocarcinoma (PEAC), a rare type of non-small cell lung cancer, has similar histological and immunohistochemical morphology to colorectal adenocarcinoma. Cadherin-17 (CDH17) and SATB homeobox 2 (SATB2) immunoexpression have recently been demonstrated in colorectal adenocarcinoma. In this study, we evaluated the value of CDH17 and SATB2 in the diagnosis of pulmonary enteric adenocarcinoma and metastatic colorectal adenocarcinoma.

Methods

A total of 13 PEAC cases and 27 metastatic colorectal adenocarcinoma cases were enrolled in our cohort study. We analyzed the expressions of CK7, CK20, CDX-2, villin, cadherin-17 (CDH17), and SATB homeobox 2 (SATB2) using immunohistochemistry. Staining intensity and percentage of positive-staining cells were recorded. Sensitivity and specificity values for immunostains, individually and in combination, were computed and compared.

Results

Combining CDH17 and SATB2 resulted in high sensitivity (76.92%) and specificity (100%). In our study, the use of CK7+, napsin A+, TTF-1+, napsin A+TTF-1+ in combination with CDH17-/SATB2- had a higher area under the curve compared to the combination CDH17-/SATB2-. However, no significant differences were observed between the combination CDH17-/SATB2- and other combinations (P>0.05).

Conclusions

In combination, CDH17 and SATB2 serve as potential optimal markers for the differential diagnosis of PEAC and metastatic colorectal adenocarcinoma.

Pulmonary enteric adenocarcinoma with pancreatic metastasis: A case report

Pulmonary enteric adenocarcinoma is a markedly rare pathological type of lung adenocarcinoma. As the pancreas is a relatively uncommon site for metastasis, the present case is even more unusual. A 62-year-old male was admitted to hospital following the identification of masses in the left chest wall, right abdominal wall and right upper limb, but with no respiratory symptoms. Computed tomography (CT) of the chest revealed a lump in the lung and a mass in the left chest wall, and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) uptake by the lumps was increased. An enhanced abdominal CT revealed a hypodense and homogeneous mass on the head of the pancreas, which was slightly enhanced compared with normal pancreatic tissue. In addition, the ¹⁸F-FDG uptake of the lesion was increased and the standardized uptake value (SUV) delayed was not evidently decreased compared with SUVearly. A number of other abnormal metabolic lesions were also identified using positron emission tomography/CT, whereas no abnormal ¹⁸F-FDG uptake was identified in the gastrointestinal organ. Furthermore, rectocolonoscopy was performed to exclude diagnosis of metastatic colorectal adenocarcinoma. The hematoxylin- and eosin-stained smears of the masses in the right lung and left chest demonstrated an enteric pattern, which shared morphological and immunohistochemical (IHC) features with those of colorectal adenocarcinoma. The IHC detection revealed that the lesions in the right lung were positive for cytokeratin 7 (CK7), and negative for CK20 and thyroid transcription factor 1 (TTF-1), and the expression of caudal type homeobox 2 (CDX2) was weakly positive; the masses in the left chest wall were positive for CK7, negative for TTF-1, and CK20 and CDX2 were weakly expressed.

MicroRNA profiling of primary pulmonary enteric adenocarcinoma in members from the same family reveals some similarities to pancreatic adenocarcinoma-a step towards personalized therapy

Background

Primary pulmonary enteric adenocarcinoma (PEAC) is defined as a pulmonary adenocarcinoma with a predominant component of intestinal differentiation and tumor cells positive for at least one intestinal marker. The aim of the present study was the molecular and histological characterization of a PEAC from a patient with two other family members affected by similar lung tumors, which has never been reported before.

Findings

We evaluated the molecular characteristics of the proband’s PEAC by using a previously validated 47-microRNA (miRNA) cancer-specific array and a predictive method to estimate tissue-of-origin probabilities. Immunohistochemical (IHC) staining for thyroid transcription factor (TTF-1), napsin A, caudal-related homeobox 2 (CDX2), cytokeratins, and mucins, as well as mutational analyses for epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS), and anaplastic lymphoma kinase (ALK) were performed on formalin-fixed, paraffin-embedded (FFPE) tissues.

The occurrence of PEAC in two family members was associated with similar clinicopathological features (age at diagnosis, smoking habit, tumor localization, multiple colonic polyps), histologic findings (TTF-1 negativity and CDX2 positivity), and genetic findings (KRAS (Gly12Asp) mutation, but no EGFR/ALK aberrations). miRNA profiling revealed similarities with non-small cell lung cancer (NSCLC; 75.98 %) and some overlap with pancreatic ductal adenocarcinoma (PDAC; 23.34 %), but not with colorectal cancer (CRC; less than 0.5 %). Notably, these PEACs share key PDAC-associated miRNAs associated with tumor aggressiveness (miR-31*/-126*/-506/-508-3p/-514).

Conclusions

We describe for the first time PEAC in members from the same family, associated with similar clinical and genetic features. miRNA profiling of the PEAC resembled a NSCLC signature, with partial overlap to a PDAC pattern. This could explain its aggressive behavior and therefore help to guide future tailored-therapeutic approaches.

Electronic supplementary material

The online version of this article (doi:10.1186/s13148-015-0162-5) contains supplementary material, which is available to authorized users.

Clinicopathological observation of primary lung enteric adenocarcinoma and its response to chemotherapy: A case report and review of the literature

Primary lung enteric adenocarcinoma is a rare type of invasive lung carcinoma. Its morphology and immunohistochemistry are those of colorectal carcinoma, but there is no associated primary colorectal carcinoma. The present study describes the case of a 53-year-old female who presented with an irritating cough and a mass around the right sternoclavicular joint. Comprehensive evaluation revealed involvement of the mediastinum, lungs, right sternoclavicular joint and right kidney. Biopsies from the mediastinal and right sternoclavicular joint tumors showed features of adenocarcinoma. Immunohistochemistry was positive for cytokeratin (CK)20 and caudal type homeobox transcription factor 2, and negative for CK7, thyroid transcription factor-1 and napsin A. Genotypic analysis identified the expression of wild-type epidermal growth factor receptor, Kirsten rat sarcoma viral oncogene homolog, serine/threonine-protein kinase B-Raf and UDP-glucuronosyltransferase 1-1. There was no expression of echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase and a moderate expression of excision repair cross-complementation group 1, ribonucleoside-diphosphate reductase large subunit and tubulin β-3 chain. A strong expression of thymidylate synthase and 677TC genotype expression of methylenetetrahydrofolate reductase was observed. Gastroscopy, enteroscopy, colorectal colonoscopy and positron emission tomography-computed tomography failed to find evidence of a gastrointestinal malignancy and primary lung enteric adenocarcinoma was diagnosed. The presence of multiple metastases did not permit curative surgery. The patient was treated with 3 monthly cycles of the XELOX chemotherapy regimen; the response was poor with progression of supraclavicular lesions. Treatment was switched to the TP regimen for 4 monthly cycles, which resulted in a significant reduction in the size of the lung lesions; however, the supraclavicular lesion responded poorly to the treatment. The patient then received 2 cycles of the FOLFIRI regimen; however, the lung and right supraclavicular lesions progressed, causing increased right upper limb pain. The pain was alleviated by palliative surgery. Following surgery, the DP regimen was employed. Follow-up of the patient remains ongoing. The present findings suggest that the early diagnosis and treatment of primary lung enteric adenocarcinoma is likely to improve patient outcome.