# Invasive mucinous adenocarcinoma of the lung

Source: https://onco.cc/cancers/invasive-mucinous-adenocarcinoma-lung/  
OnCo record `invasive-mucinous-adenocarcinoma-lung` (Cancer). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Invasive mucinous adenocarcinoma is a type of lung cancer whose cells look like stomach or bowel lining and fill the air spaces with mucus, often appearing as pneumonia-like shadows on a scan. Most cases carry a KRAS mutation, and many of the rest carry a gene fusion, including NRG1, that new drugs can target.

## Summary

The IASLC/ATS/ERS classification of 2011 separated invasive mucinous adenocarcinoma from the non-mucinous lepidic tumours because of its distinct cells (goblet or columnar with abundant mucin), its tendency to spread through the airways as multifocal or lobar consolidation, and its biology (Travis 2011). Sequencing of 72 cases found KRAS mutations in 63 percent, with a distribution of nucleotide changes closer to gastrointestinal than to other lung tumours; among the KRAS wild-type cases were the fusions CD74-NRG1, VAMP2-NRG1, TRIM4-BRAF, TPM3-NTRK1 and EML4-ALK and mutations in ERBB2 and other genes (Shim 2015). Expression profiling identified a 143-gene mucinous signature, shared with mucin-producing gastrointestinal, pancreatic and breast cancers, in which the transcription factors FOXA3, SPDEF and HNF4A drive MUC5AC and MUC5B, and in which the checkpoint VTCN1 rather than PD-L1 is expressed (EMBO Molecular Medicine 2017).

How it differs from its parent: it is TTF-1-negative and expresses gut markers, so it can be mistaken for a metastasis; it is EGFR-mutant only rarely; and it is the lung cancer richest in NRG1 fusions, for which the HER2-HER3 bispecific antibody zenocutuzumab is approved.

How common: no share is given in the sources read; it is a minority of adenocarcinomas.

Treatment: as lung adenocarcinoma by stage, with KRAS G12C inhibitors for that mutation, zenocutuzumab for NRG1 fusions, and the matching inhibitors for ALK, BRAF and NTRK fusions; multifocal disease that stays in the lung is sometimes resected repeatedly.

## Fields

- Kind: Cancer
- Last checked: 2026-09-24
- Also known as: Invasive mucinous adenocarcinoma; IMA; Mucinous bronchioloalveolar carcinoma (term retired in 2011); Mucinous adenocarcinoma of the lung
- Tags: subtype-page; wave4; lung
- Group: lung
- Burden: A minority of lung adenocarcinomas; the defining genomic series studied 72 cases from the United States and Korea (Shim 2015). No registry share was found in the sources read.
- Subtypes: KRAS-mutant invasive mucinous adenocarcinoma (63 percent); NRG1 fusion-positive invasive mucinous adenocarcinoma; Invasive mucinous adenocarcinoma with ALK, BRAF or NTRK fusion; Mixed invasive mucinous and non-mucinous adenocarcinoma
- Biomarkers: KRAS mutation (G12C and non-G12C); NRG1 fusion; ALK, BRAF, NTRK1 and ERBB2 alterations in KRAS wild-type cases; TTF-1 negative, HNF4A and gut markers positive

## Sections of this record

The page is a hub with ten sections in reading order; large sections have their own page. The same plan as JSON: https://onco.cc/api/v1/cancers/invasive-mucinous-adenocarcinoma-lung/sections.json

- Overview (on the hub): The TL;DR, the family this cancer belongs to, the organ, who gets it and what the state of the art is. https://onco.cc/cancers/invasive-mucinous-adenocarcinoma-lung/#overview
- What it is (on the hub): Anatomy, the subtypes and how they differ, how it is staged, and where advanced disease spreads. https://onco.cc/cancers/invasive-mucinous-adenocarcinoma-lung/#what-it-is [4 subtypes]
- Finding it (on the hub): How it shows itself, how it is confirmed, what screening exists, and the biomarkers clinicians test for. https://onco.cc/cancers/invasive-mucinous-adenocarcinoma-lung/#finding-it [4 biomarkers]
- Treating it (on the hub): The standard of care by setting, the medicines, surgery and radiotherapy named in it, and the regimens behind them. https://onco.cc/cancers/invasive-mucinous-adenocarcinoma-lung/#treating-it [1 setting]
- Evidence (on the hub): Trials recruiting now, the landmark trials, the key papers and what they mean, the latest literature, and the milestones year by year. https://onco.cc/cancers/invasive-mucinous-adenocarcinoma-lung/#evidence
- The science (on the hub): The molecular landscape: the targets and how often each appears, the pathways, the mechanics stages and the preclinical models. https://onco.cc/cancers/invasive-mucinous-adenocarcinoma-lung/#science [4 targets]
- Where you are (own page): Cases by country, the UK and NHS pathway and other country lenses, and the expert centres with trials on record. https://onco.cc/cancers/invasive-mucinous-adenocarcinoma-lung/where-you-are/
- Living with it (on the hub): The decisions you may face, the aids that walk through them, the warnings on record, the first sixty days and the questions to ask. https://onco.cc/cancers/invasive-mucinous-adenocarcinoma-lung/#living-with-it [8 questions]
- What is coming (own page): Everything in development, the open problems and what is being done about them, the roadmaps, and what changed on this record. https://onco.cc/cancers/invasive-mucinous-adenocarcinoma-lung/coming/ [1 medicine]
- Data (own page): Every connected record, the notes, the JSON, Markdown and RDF twins, and where the record came from and when it was checked. https://onco.cc/cancers/invasive-mucinous-adenocarcinoma-lung/data/ [7 connected records]

## Standard of care

- All stages: Treated as lung adenocarcinoma by stage, with KRAS G12C inhibitors, zenocutuzumab for NRG1 fusions and matched inhibitors for other fusions when found. ([Adenocarcinoma of the lung](https://onco.cc/cancers/lung-adenocarcinoma/), [KRAS G12C-mutant non-small-cell lung cancer](https://onco.cc/cancers/kras-g12c-nsclc/), [Zenocutuzumab](https://onco.cc/drugs/zenocutuzumab/))

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Adenocarcinoma_of_the_lung
- Travis 2011, JTO: IASLC/ATS/ERS international multidisciplinary classification of lung adenocarcinoma: https://doi.org/10.1097/jto.0b013e318206a221
- Nicholson 2022, JTO: the 2021 WHO classification of lung tumours: https://doi.org/10.1016/j.jtho.2021.11.003
- Shim 2015, JTO: unique genetic and survival characteristics of invasive mucinous adenocarcinoma of the lung: https://doi.org/10.1097/jto.0000000000000579
- EMBO Molecular Medicine 2017: gene signature driving invasive mucinous adenocarcinoma of the lung: https://doi.org/10.15252/emmm.201606711

## Connected records

- cancers: [Adenocarcinoma in situ and minimally invasive adenocarcinoma of the lung](https://onco.cc/cancers/lung-adenocarcinoma-in-situ-and-minimally-invasive/), [Adenocarcinoma of the lung](https://onco.cc/cancers/lung-adenocarcinoma/), [KRAS G12C-mutant non-small-cell lung cancer](https://onco.cc/cancers/kras-g12c-nsclc/), [Non-small-cell lung cancer](https://onco.cc/cancers/nsclc/)
- targets: [KRAS](https://onco.cc/targets/kras/), [NRG1](https://onco.cc/targets/nrg1/)
- drugs: [Zenocutuzumab](https://onco.cc/drugs/zenocutuzumab/)

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JSON: https://onco.cc/api/v1/entities/invasive-mucinous-adenocarcinoma-lung.json