Molecular Pathogenesis of Penile Squamous Cell Carcinoma: Current Understanding and Potential Treatment Implications.

CONTEXT.­: Penile squamous cell carcinomas (PSCCs) are divided into tumors that are human papillomavirus (HPV) associated and those that are non-HPV associated. HPV and non-HPV PSCCs each display unique pathogenic mechanisms, histologic subtypes, and clinical behaviors. Treatment of localized PSCC tumors is linked to significant physical and psychological morbidity, and management of advanced disease is often treatment refractory. The identification of novel actionable mutations is of critical importance so that translational scientists and clinicians alike can pursue additional therapeutic options. OBJECTIVE.­: To provide an update on the molecular pathogenesis associated with PSCC. A special emphasis is placed on next-generation sequencing data and its role in identifying potential therapeutic targets. DATA SOURCES.­: A literature review using the PubMed search engine to access peer-reviewed literature published on PSCC. CONCLUSIONS.­: Our understanding of the genetic and molecular mechanisms that underlie PSCC pathogenesis continues to evolve. PSCC tumorigenesis is mediated by multiple pathways, and mutations of oncogenic significance have been identified that may represent targets for personalized therapy. Preliminary results of treatment with immune checkpoint inhibition and tyrosine kinase inhibitors have produced variable clinical results. Further insight into the pathogenesis of PSCC will help guide clinical trials and develop additional precision medicine approaches.

The need for speed in advanced non-small cell lung cancer: A population kinetics assessment.

BACKGROUND: Systemic therapy prolongs overall survival (OS) in advanced non-small cell lung cancer (NSCLC), but diagnostic tests, staging and molecular profiling take time, and this can delay therapy initiation. OS approximates first-order kinetics. METHODS: We used OS of chemo-naive NSCLC patients on a placebo/best supportive care trial arm to estimate % of patients dying while awaiting therapy. We digitized survival curves from eight studies, calculated OS half-life, then estimated the proportion surviving after different times of interest (tn ) using the formula: X=exp-tn∗0.693/t1/2 , where EXP signifies exponential, * indicates multiplication, 0.693 is the natural log of 2, and t1/2 is the survival half-life in weeks. RESULTS: Across trials, the OS half-life for placebo/best supportive care in previously untreated NSCLC was 19.5 weeks. Hence, based on calculations using the formula above, if therapy were delayed by 1, 2, 3, or 4 weeks then 4%, 7%, 10%, and 13% of all patients, respectively, would die while awaiting treatment. Others would become too sick to consider therapy even if still alive. CONCLUSIONS: This quantifies why rapid baseline testing and prompt therapy initiation are important in advanced NSCLC. It also illustrates why screening procedures for clinical trial inclusion must be faster. Otherwise, it is potentially hazardous for a patient to be considered for a trial due to risk of death or deterioration while awaiting eligibility assessment. It is also important to not delay initiation of systemic therapy for procedures that add relatively little value, such as radiotherapy for small, asymptomatic brain metastases.

Guiding Principles on the Importance of Thoracic Surgical Education on Establishing Integrated Thoracic Surgery Program, Interdisciplinary Thoracic Oncology Conferences, and an Interdisciplinary Approach to Management of Thoracic Malignancies.

The objective of these notes is to stress the principles underlying the management of primary lung cancers and other types of malignancies in the thorax-diffuse malignant mesothelioma, invasive mediastinal tumors, chest wall sarcoma, and tracheal neoplasms-and from these considerations to outline a routine scheme for management, which can be followed easily by all staff. It is hoped that by adherence to this routine, adequate and efficient management of all cases will be obtained, both in the very important matter of preoperative preparation, as well in the postoperative management.

The Lymphatic Spread of Lung Cancer: An Investigation of the Anatomy of the Lymphatic Drainage of the Lungs and Preoperative Mediastinal Staging.

The knowledge of lymphatic spread of lung cancer permitted the study of anatomy of lymphatic drainage of the lungs. The history of anatomy of lymphatic drainage of the lungs began in the 15th century. In the human, pulmonary lymph flows to the lymph nodes around the lobar bronchi and thence to extrapulmonary lymph nodes located around the main bronchi and trachea and its bifurcation (tracheobronchial lymph nodes). These send their efferents to a right and left mediastinal lymph trunks, which may join the thoracic duct, but usually drain opening directly into the brachiocephalic vein of their own side.

Combination of MCM2 With Ki67 and p16 Immunohistochemistry Can Distinguish Uterine Leiomyosarcomas.

Our objective was to evaluate the diagnostic utility of 2 new proliferation markers, cyclin D1 and minichromosome maintenance complex component 2 (MCM2), in comparison with p16, p53, and Ki67 in differentiating the spectrum of smooth muscle tumors. An institutional database search from 2009 to 2017 identified 10 cases of uterine leiomyoma with bizarre nuclei (LBN), 12 smooth muscle tumors of uncertain malignant potential, and 13 leiomyosarcomas (LMS). Ten resected leiomyomas (LM) were included as controls. Immunohistochemistry was performed on the befitting representative block from each case. Ki67 was <10% in all LMs and LBNs, whereas >10% in all LMSs. Although wild-type in majority of cases, p53 was overexpressed in 38% of LMSs. Cyclin D1 nuclear positivity in LMs, LBNs, and smooth muscle tumors of uncertain malignant potentials ranged from 0% to 65% of neoplastic cells with mostly weak to moderate staining intensity. Instead, cyclin D1 expression was <5% in all LMSs. The ratio of MCM2 positivity exhibited a similar wide range (<1%-80%) in LMs, LBNs, and smooth muscle tumors of uncertain malignant potentials but interestingly, 92% (12/13) of LMSs were diffusely and strongly positive for MCM2 (>80% cell positivity). Overall, for diagnosis of LMS, the sensitivity for diffuse intense MCM2 staining was higher (92%) compared with diffuse staining for p16 (77%); however, specificity of MCM2 and p16 was comparable (94% and 97%, respectively). Herein, we describe the immunohistochemical profile of 2 new proliferation markers, cyclin D1 and MCM2 in uterine smooth muscle tumors. A combination of diffuse strong MCM2 and p16 reactivity with increased Ki67 index can reliably distinguish LMSs from benign histologic mimics.

Canadian Multicenter Project on Standardization of Programmed Death-Ligand 1 Immunohistochemistry 22C3 Laboratory-Developed Tests for Pembrolizumab Therapy in NSCLC.

INTRODUCTION: The programmed death-ligand 1 (PD-L1) immunohistochemistry (IHC) assay is used to select patients for first or second-line pembrolizumab monotherapy in NSCLC. The PD-L1 IHC 22C3 pharmDx assay requires an Autostainer Link 48 instrument. Laboratories without this stainer have the option to develop a highly accurate 22C3 IHC laboratory-developed test (LDT) on other instruments. The Canadian 22C3 IHC LDT validation project was initiated to harmonize the quality of PD-L1 22C3 IHC LDT protocols across 20 Canadian pathology laboratories. METHODS: Centrally optimized 22C3 LDT protocols were distributed to participating laboratories. The LDT results were assessed against results using reference PD-L1 IHC 22C3 pharmDx. Analytical sensitivity and specificity were assessed using cell lines with varying PD-L1 expression levels (phase 1) and IHC critical assay performance controls (phase 2B). Diagnostic sensitivity and specificity were assessed using whole sections of 50 NSCLC cases (phase 2A) and tissue microarrays with an additional 50 NSCLC cases (phase 2C). RESULTS: In phase 1, 80% of participants reached acceptance criteria for analytical performance in the first attempt with disseminated protocols. However, in phase 2A, only 40% of participants reached the desired diagnostic accuracy for both 1% and 50% tumor proportion score cutoff. In phase 2B, further protocol modifications were conducted, which increased the number of successful laboratories to 75% in phase 2C. CONCLUSIONS: It is possible to harmonize highly accurate 22C3 LDTs for both 1% and 50% tumor proportion score in NSCLC across many laboratories with different platforms. However, despite a centralized approach, diagnostic validation of predictive IHC LDTs can be challenging and not always successful.

Sclerosing Pneumocytoma of the Lungs Arising in a Child With PTEN Mutation.

We report a rare case of sclerosing pneumocytoma occurring in a child with PTEN mutation. A 13-year-old female presented to the emergency department of an adult hospital following 2 to 3 days of upper respiratory tract infection symptoms. A primary lung lesion was discovered during her initial chest X-ray to rule out pneumonia. The patient underwent an uneventful thoracoscopic right upper lobe segmentectomy. The pathology demonstrated a sclerosing pneumocytoma of the lung. She tested positive for PTEN hamartoma tumor syndrome with a pathogenic variant at c.388 C > T. The PTEN mutation was also identified in the sclerosing pneumocytoma. Further study of PTEN mutation in sclerosing pneumocytoma is warranted.

Translation of Knowledge to Practice-Improving Awareness in NSCLC Molecular Testing.

BACKGROUND: Molecular testing in advanced lung cancer is standard in guiding treatment selection. However, population-wide implementation of testing remains a challenge. We developed a knowledge translation intervention to improve understanding among diagnostic specialists about molecular testing and appropriate diagnostic sampling in lung cancer. METHODS: Specialty-specific education programs were developed from existing literature and input from Canadian leaders in lung pathology, respirology, interventional radiology, thoracic surgery, radiation oncology, and medical oncology. The programs, including key messages, review of current data, existing guidelines, group discussion, and participant feedback, were administered at provincial and national specialty meetings. Participant knowledge was assessed before and after the intervention by using anonymous questionnaires. Molecular (EGFR) testing rates in Ontario were also evaluated before and after the intervention period. RESULTS: Ten programs were administered to diagnostic specialists, including respirologists, pathologists, thoracic surgeons, radiologists, radiation oncologists, and medical oncologists, with completion of 255 preintervention and 219 postintervention surveys. At baseline, 30% were unsure of tissue handling methods for molecular testing, 20% chose an incorrect technique, and half were unfamiliar with how to initiate testing. After intervention, specialist knowledge improved regarding tissue handling and appropriate fixation techniques and uncertainty decreased from 30% to 2% (p < 0.001). A 12% increase (relative increase 57%) in molecular (EGFR) testing requests in Ontario was observed over the intervention period (p = 0.0032). CONCLUSIONS: Significant knowledge gaps exist among diagnostic specialists regarding molecular testing and targeted therapy in lung cancer. This initiative significantly improved understanding of the importance and methods of successful molecular testing and correlated with increased testing rates.

Vulvar Squamous Cell Carcinoma (VSCC) as Two Diseases: HPV Status Identifies Distinct Mutational Profiles Including Oncogenic Fibroblast Growth Factor Receptor 3.

Purpose: Patients with advanced or recurrent invasive vulvar squamous cell carcinoma (VSCC) have limited treatment options and a grave prognosis. Understanding the genomic landscape may facilitate the identification of new therapies and improve clinical outcomes.Experimental Design: A retrospective chart review and molecular analysis of patients with VSCC from 2000 to 2016 was performed at the Ottawa Hospital Research Institute. The presence of oncogenic human papillomavirus (HPV) was determined by nested PCR and amplified DNA was sequenced using the Ion AmpliSeq Cancer Hotspot v2 Panel. The patients were divided into two groups according to HPV status (HPV-positive versus HPV-negative) and clinical outcome correlated with mutation status using descriptive statistics.Results: In 43 VSCC patients, there was a high mutation rate in both HPV-positive (73%) and HPV-negative (90%) disease with the two subgroups expressing distinct genetic profiles. HPV-positive tumors were characterized by oncogenic mutations in PIK3CA (27%), FGFR3 (14%), and PTEN (9%), whereas HPV-negative tumors were found to have mutations in TP53 (57%), HRAS (24%), PI3KCA (19%), and CDKN2A (14%). Mutation S249C in FGFR3 occurred in 14% of HPV-positive tumors. While there were notable differences in the occurrence of TP53, HRAS, PTEN, and FGFR3 mutations according to HPV status, only the rate of TP53 mutations was statistically significant (P = 0.0004). No significant difference in prognosis was found between patients with HPV-positive and HPV-negative VSCC.Conclusions: HPV-positive VSCC is characterized by oncogenic FGFR3 mutations that helps classify this subtype as a separate disease. Inhibitors of FGFR3 merit consideration as a therapeutic strategy in this neglected cancer in women. Clin Cancer Res; 23(15); 4501-10. ©2017 AACR.

Cyclooxygenase-2 (COX-2) inhibition for prostate cancer chemoprevention: double-blind randomised study of pre-prostatectomy celecoxib or placebo.

OBJECTIVE: To evaluate the biological effects of selective cyclooxygenase-2 inhibition on prostate tissue in patients undergoing radical prostatectomy (RP). PATIENTS AND METHODS: Patients with localised prostate cancer were randomised to receive either celecoxib 400 mg twice daily or placebo for 4 weeks before RP. Specimens were analysed for levels of apoptosis, prostaglandins, and androgen receptor (AR). Effects on serum prostate-specific antigen (PSA) and postoperative opioid use were also measured. RESULTS: In all, 28 of 44 anticipated patients enrolled and completed treatment. One patient in the celecoxib arm had a myocardial infarction postoperatively. For this reason, and safety concerns in other studies, enrolment was halted. The apoptosis index (AI) in tumour cells was 0.29% [95% confidence interval (CI) 0.11-0.47%] vs 0.39% (95% CI 0.00-0.84%) in the celecoxib and placebo arms, respectively (P = 0.68). The AI in benign cells was 0.18% (95% CI 0.03-0.32%) vs 0.13% (95% CI 0.00-0.28%) in the celecoxib and placebo arms, respectively (P = 0.67). Prostaglandin E2 and AR levels were similar in cancerous and benign tissues when comparing the two arms. The median baseline PSA level was 6.0 and 6.2 ng/mL for the celecoxib and placebo groups, respectively, and did not significantly change after celecoxib treatment. There was no difference in postoperative opiate usage between arms. CONCLUSION: Celecoxib had no effect on apoptosis, prostaglandins or AR levels in cancerous or benign prostate tissues. These findings coupled with drug safety concerns should serve to limit interest in these selective drugs as chemopreventive agents.

Correction: Influenza Virus Targets Class I MHC-Educated NK Cells for Immunoevasion.

[This corrects the article DOI: 10.1371/journal.ppat.1005446.].

Complete pathological response following neoadjuvant FOLFIRINOX in borderline resectable pancreatic cancer - a case report and review.

BACKGROUND: Pancreatic cancer is among the top 5 most common cancers worldwide, but is particularly devastating due to its insidious nature. Complete surgical resection remains the only potential curative treatment, although only 20 % of patients present with a resectable tumor. Patients may alternatively present with borderline resectable pancreatic cancer or locally advanced pancreatic cancer and can be offered treatment with neoadjuvant intent. The effectiveness of these treatments is unclear and there is a paucity of data to suggest one optimal treatment approach. CASE PRESENTATION: We describe a 61-year-old female who presented with a two-week history of obstructive jaundice in the context of vague abdominal pain that had been ongoing for years prior to her visit. CT scan of the abdomen confirmed a hypovascular mass in the uncinate process consistent with borderline resectable pancreatic cancer. Pancreatic adenocarcinoma was confirmed with endoscopic ultrasound guided fine-needle aspiration cytology. Following multidisciplinary discussion, it was recommended that she undergo treatment with FOLFIRINOX. After a total of 13 cycles, follow up CT revealed that the lesion had decreased in size and she was offered resection as a potentially curative treatment. She underwent pancreaticoduodenectomy. Final pathology report revealed no evidence of residual adenocarcinoma (ypT0 ypN0 (0/23)). The patient remains disease-free 15 months following surgery. CONCLUSION: To date, there have been very few reports of a complete pathological response following neoadjuvant therapy in borderline resectable or locally advanced pancreatic cancer. This report describes a unique case of a complete pathological remission in a patient with borderline resectable pancreatic cancer following FOLFIRINOX therapy alone and adds to the growing base of evidence meriting the initiation of clinical trials to assess the efficacy of FOLFIRINOX in these subsets of pancreatic cancer.

Recurrence of a Thymic Carcinoid Tumour 15 Years After Resection With Multiple Myopericardial Cardiac Metastases: The Role of Multimodality Imaging.

Carcinoid tumours arising from the thymus are exceedingly rare, and cardiac metastases have not previously been described in the setting of a primary thymic carcinoid tumour. We present a patient with recurrence of a carcinoid tumour initially resected from the thymus 15 years earlier, with multiple cardiac metastases. These metastatic tumours were visualized using multiple imaging modalities, including computed tomography, transthoracic echocardiogram, magnetic resonance imaging, and octreotide scan. A subsequent biopsy confirmed recurrence of his carcinoid tumour. This case highlights the role of multimodality imaging for diagnosis and the need for continued long-term surveillance in these patients.

Influenza Virus Targets Class I MHC-Educated NK Cells for Immunoevasion.

The immune response to influenza virus infection comprises both innate and adaptive defenses. NK cells play an early role in the destruction of tumors and virally-infected cells. NK cells express a variety of inhibitory receptors, including those of the Ly49 family, which are functional homologs of human killer-cell immunoglobulin-like receptors (KIR). Like human KIR, Ly49 receptors inhibit NK cell-mediated lysis by binding to major histocompatibility complex class I (MHC-I) molecules that are expressed on normal cells. During NK cell maturation, the interaction of NK cell inhibitory Ly49 receptors with their MHC-I ligands results in two types of NK cells: licensed ("functional"), or unlicensed ("hypofunctional"). Despite being completely dysfunctional with regard to rejecting MHC-I-deficient cells, unlicensed NK cells represent up to half of the mature NK cell pool in rodents and humans, suggesting an alternative role for these cells in host defense. Here, we demonstrate that after influenza infection, MHC-I expression on lung epithelial cells is upregulated, and mice bearing unlicensed NK cells (Ly49-deficient NKCKD and MHC-I-deficient B2m-/- mice) survive the infection better than WT mice. Importantly, transgenic expression of an inhibitory self-MHC-I-specific Ly49 receptor in NKCKD mice restores WT influenza susceptibility, confirming a direct role for Ly49. Conversely, F(ab')2-mediated blockade of self-MHC-I-specific Ly49 inhibitory receptors protects WT mice from influenza virus infection. Mechanistically, perforin-deficient NKCKD mice succumb to influenza infection rapidly, indicating that direct cytotoxicity is necessary for unlicensed NK cell-mediated protection. Our findings demonstrate that Ly49:MHC-I interactions play a critical role in influenza virus pathogenesis. We suggest a similar role may be conserved in human KIR, and their blockade may be protective in humans.

Three-dimensional cell groups with disordered nuclei and cellular discohesion (3DDD) are associated with high sensitivity and specificity for cystoscopic urine cytopathological diagnosis of low-grade urothelial neoplasia.

Cystoscopic urine obtained before the resection of low-grade urothelial carcinoma (LGUC), with adequate cytological sampling of the tumor, frequently revealed the presence of three-dimensional cell groups with disordered nuclei and cellular discohesion (3DDD). 936 cystoscopic urine specimens were categorized into five groups: Group 1 (80 specimens) with biopsy-proven LGUC within 6 months of cytologic examination, Group 2 (23 specimens) with biopsy proven LGUC within 6 to 36 months of cytologic examination, Group 3 (527 specimens) with a history of LGUC but no tumor for a period of greater than 3 years, Group 4 (300 specimens) with no association with LGUC, and Group 5 (6 specimens) with urinary lithiasis. Specimens with scant cellularity accounted for 20% of those in Group 1. For 3DDD in detecting LGUC in adequate cystoscopic urine, the sensitivity was 70%, specificity was 94%. Two- or three-dimensional cell groups with ordered nuclei and/or cellular non-discohesion were often seen in specimens from Groups 4 or 5. The 3DDD was present in a significant number of cases with concurrent negative cystoscopic findings but also positive LGUC in ensuing follow-up. In these cases, 3DDD with or without tumor identified at concurrent cystoscopy were found to be morphologically similar. Furthermore, the presence of 3DDD in 8% of Group 3 likely represents urothelial dysplasia that is not cystoscopically detectable. The high specificity and sensitivity of 3DDD is demonstrated. These findings are consistent with the decreased cell adhesion and disordered nuclear arrangement of low grade urothelial neoplasia.

Diffuse intrapulmonary neuroendocrine cell hyperplasia.

Diffuse intrapulmonary neuroendocrine cell hyperplasia is a rare, potential precursor lesion to typical pulmonary carcinoid tumours. Fewer than 50 cases have been reported in the literature. Their pathogenesis, clinical significance and management is controversial. A patient who presented with diffuse intrapulmonary neuroendocrine cell hyperplasia associated with a primary typical carcinoid tumour of the lung is reported.

Factors influencing a specific pathologic diagnosis of non-small-cell lung carcinoma.

INTRODUCTION: Historically, a non-small-cell lung carcinoma diagnosis, without pathologic subclassification, provided sufficient information to guide therapy. Evidence now demonstrates that pathologic subtype classification is central in selecting optimal treatment. This review aimed to identify factors associated with a specific pathologic diagnosis. METHODS: All nonoperative cases of non-small-cell lung carcinoma (NSCLC) referred to the medical oncology divisions of the Ottawa Hospital Cancer Centre (2008) and Princess Margaret Hospital, Toronto (2007-2010) were identified. The charts were reviewed for demographics, diagnostic methods, and final diagnosis. Logistic regression was performed to identify variables associated with a specific diagnosis. RESULTS: Of 739 patient records analyzed, 377 (51%) were men, 299 (40%) were aged over 70 years, and 510 (69%) had an Eastern Cooperative Oncology Group performance status of 0-2. Three hundred and eighty five (52%) of patients were diagnosed in a tertiary academic center. The lung primary was sampled in 503 (68%) of patients. Computed tomography-guided biopsy (n = 370, 50%) and bronchoscopy (n = 179, 24%) were the most common techniques. Four hundred and seventy seven (65%) of biopsies were cytologic specimens alone, and immunohistochemistry was performed in 337 (46%) of cases. The most common diagnoses were adenocarcinoma (n = 338, 46%), NSCLC not otherwise specified (n = 254, 34%), and squamous cell carcinoma (n = 115, 16%). Overall, 456 (62%) of patients received a specific pathologic diagnosis. Factors significantly associated with attaining a specific pathologic diagnosis were diagnosis outside an academic center (adjusted odds ratios [OR] 2.1 [95% CI, 1.41-3.14]; P = .0003), histologic laboratory samples (adjusted OR 1.58 [95% CI, 1.003-2.49]; P = .049), and immunohistochemical testing (adjusted OR 1.82 [95% CI, 1.25-2.70], P = .0021). CONCLUSIONS: A significant minority of patients with NSCLC do not receive a specific pathologic diagnosis. In an era of individualized medicine, this may potentially impact optimal clinical management.

Mouse Nkrp1-Clr gene cluster sequence and expression analyses reveal conservation of tissue-specific MHC-independent immunosurveillance.

The Nkrp1 (Klrb1)-Clr (Clec2) genes encode a receptor-ligand system utilized by NK cells as an MHC-independent immunosurveillance strategy for innate immune responses. The related Ly49 family of MHC-I receptors displays extreme allelic polymorphism and haplotype plasticity. In contrast, previous BAC-mapping and aCGH studies in the mouse suggest the neighboring and related Nkrp1-Clr cluster is evolutionarily stable. To definitively compare the relative evolutionary rate of Nkrp1-Clr vs. Ly49 gene clusters, the Nkrp1-Clr gene clusters from two Ly49 haplotype-disparate inbred mouse strains, BALB/c and 129S6, were sequenced. Both Nkrp1-Clr gene cluster sequences are highly similar to the C57BL/6 reference sequence, displaying the same gene numbers and order, complete pseudogenes, and gene fragments. The Nkrp1-Clr clusters contain a strikingly dissimilar proportion of repetitive elements compared to the Ly49 clusters, suggesting that certain elements may be partly responsible for the highly disparate Ly49 vs. Nkrp1 evolutionary rate. Focused allelic polymorphisms were found within the Nkrp1b/d (Klrb1b), Nkrp1c (Klrb1c), and Clr-c (Clec2f) genes, suggestive of possible immune selection. Cell-type specific transcription of Nkrp1-Clr genes in a large panel of tissues/organs was determined. Clr-b (Clec2d) and Clr-g (Clec2i) showed wide expression, while other Clr genes showed more tissue-specific expression patterns. In situ hybridization revealed specific expression of various members of the Clr family in leukocytes/hematopoietic cells of immune organs, various tissue-restricted epithelial cells (including intestinal, kidney tubular, lung, and corneal progenitor epithelial cells), as well as myocytes. In summary, the Nkrp1-Clr gene cluster appears to evolve more slowly relative to the related Ly49 cluster, and likely regulates innate immunosurveillance in a tissue-specific manner.

Primary adenocarcinoma of lung: a pictorial review of recent updates.

Primary adenocarcinoma of lung has replaced squamous cell carcinoma as the commonest histological subtype of lung cancer and the incidence of primary lung adenocarcinoma appears to be rising. Although the main factors behind this 'epidemic-like' situation are largely undiscovered, filter cigarettes appear to significantly contribute to this shift in the histopathological spectrum. The new multidisciplinary classification of adenocarcinoma of lung was introduced to address advances in clinical, pathological, radiological and molecular sciences. The purpose of this essay is to discuss various classes of lung adenocarcinoma in the new classification with their classical imaging features on computed tomography and summarise the recent advances in the field of radiology and review radiology recommendations.