1. Findings
code lungs pulmonary mass RUL neoplasm malignant primary lymphatics lymphangitis imaging plain film CXR CTscan PETscan
Differential Diagnosis Table
| Disease | TCV Category | Reasoning |
|---|---|---|
| Primary lung adenocarcinoma with lymphangitic spread | Neoplasm – Malignant | Upper lobe mass + interstitial pattern typical for lymphangitic carcinomatosis |
| Sarcoidosis | Inflammatory/Immune | May show upper lobe nodules and fibrosis; but mass lesion is atypical |
| Pulmonary tuberculosis | Infectious | Can cause upper lobe mass-like consolidation and nodular interstitial thickening |
| Lymphoma | Neoplasm – Malignant | Can present as large mass with interstitial spread; less common than carcinoma |
| Pulmonary metastases with lymphangitis | Neoplasm – Metastatic | Hematogenous spread can mimic adenocarcinoma with interstitial thickening |
| Chronic hypersensitivity pneumonitis | Inflammatory/Immune | Interstitial process more diffuse and lower lobe predominant; no focal mass |
2. Diagnosis
Dx: Adenocarcinoma with Lymphangitis Carcinomatosa
Radiologic Diagnosis Table
| Radiologic Feature | Description (CXR) |
|---|---|
| Location | Right upper lobe (RUL) mass |
| Mass characteristics | Lrge mass; solitary peripheral |
| Interstitial pattern | Fine reticulonodular opacities radiating from mass |
| Distribution | Follows bronchovascular bundles and septa (suggesting lymphatic spread) |
| Associated signs | May show mild volume loss, subtle hilar/mediastinal adenopathy |
| Modality notes | CXR suggests pattern, but CT confirms lymphangitic carcinomatosis and characterizes the mass |
Takeaway Points
-
RUL peripheral mass with radiating interstitial lines is a classic radiographic clue to lymphangitic spread
-
CXR can suggest diagnosis, but CT is required for confirmation and staging
-
Pattern of spread along septa and peribronchovascular bundles is key to diagnosis
-
Differentiation from infection or fibrosis requires clinical context and imaging correlation
Radiologic References (Guidelines Only)
-
ACR Appropriateness Criteria: Chronic Dyspnea
-
ACR Appropriateness Criteria: Lung Cancer Screening
-
RSNA Consensus White Paper: Lymphangitic Carcinomatosis
3. Info
Table 1 – Broad Disease Context
| Category | Details |
|---|---|
| Definition | Adenocarcinoma is a malignant tumor arising from alveolar epithelial cells (commonly Type II pneumocytes). Lymphangitic carcinomatosis refers to tumor spread along pulmonary lymphatic vessels. |
| Caused by | – Primary lung adenocarcinoma (most common) – Less often from metastatic cancers (breast, colon, stomach, pancreas) |
| Resulting in | – Lymphatic obstruction and interstitial infiltration – Impaired gas exchange and progressive dyspnea |
| Structural Changes | – Spiculated or ill-defined mass – Smooth or nodular interlobular septal thickening – Peribronchovascular thickening – Possible hilar/mediastinal adenopathy |
| Functional Changes | – Hypoxemia due to lymphatic and alveolar disruption – Reduced pulmonary compliance and diffusion capacity |
| Diagnosis – Clinical | – Progressive dyspnea, chronic cough, fatigue, weight loss |
| Diagnosis – Imaging | – CT : Most sensitive; shows mass + septal thickening – PET/CT: Hypermetabolic activity in mass and interstitial regions |
| Diagnosis – Lab/Other | – Biopsy confirms adenocarcinoma – Molecular testing: EGFR, ALK, KRAS – Elevated tumor markers possible (e.g., CEA) |
| Usually Treated by | – Systemic chemotherapy – Targeted therapy (based on mutations) – Immunotherapy (PD-1/PD-L1 inhibitors) – Radiation for palliation – Supportive/palliative care |
Table 2 – Radiology Detail: Variants & Modalities
| Pattern / Subtype | Imaging Features |
|---|---|
| Solid spiculated adenocarcinoma | Peripheral irregular mass; often shows pleural retraction |
| Adenocarcinoma in situ (AIS) | Pure ground-glass nodule; slow-growing |
| Minimally invasive adenocarcinoma (MIA) | Part-solid nodule with central solid component |
| Pneumonic-type adenocarcinoma | Lobar consolidation mimicking infection |
| Lymphangitic spread (this case) | Septal and bronchovascular thickening with a mass |
Takeaway & Pearls
-
Pattern recognition: Lymphangitic carcinomatosis is a classic “spider web” interstitial pattern radiating from a mass
-
Adenocarcinoma is radiologically diverse – patterns include solid, GGO, part-solid, and consolidation
-
PET/CT and HRCT are essential for staging and guiding biopsy
-
Always correlate with clinical progression and pursue tissue confirmation
4. MCQ
MCQs (7 Questions)
Basic Science
Q1. What cell type is the most common origin of lung adenocarcinoma?
A) Type I pneumocytes
B) Type II pneumocytes
C) Goblet cells
D) Basal cells
Correct Answer: B) Type II pneumocytes
-
Explanation: Type II pneumocytes are progenitor cells involved in alveolar repair and are the most common origin of lung adenocarcinomas.
-
A is incorrect: Type I pneumocytes are thin and specialized for gas exchange—not regenerative.
-
C is incorrect: Goblet cells secrete mucus and are more prominent in airway disease.
-
D is incorrect: Basal cells regenerate airway epithelium, not alveolar structures.
Q2. Which genetic mutation is most commonly associated with lung adenocarcinoma in non-smokers?
A) KRAS
B) p53
C) EGFR
D) ALK
Correct Answer: C) EGFR
-
Explanation: EGFR mutations are prevalent in non-smoking patients with adenocarcinoma and guide targeted therapy.
-
A is incorrect: KRAS is more common in smokers and associated with poor prognosis.
-
B is incorrect: p53 is a nonspecific tumor suppressor mutated in many cancers.
-
D is incorrect: ALK rearrangements occur in a subset, but less frequently than EGFR.
Clinical
Q3. Which clinical feature is most indicative of lymphangitic carcinomatosis?
A) Acute pleuritic chest pain
B) Hemoptysis
C) Progressive dyspnea
D) Hoarseness
Correct Answer: C) Progressive dyspnea
-
Explanation: Tumor spread in lymphatics restricts gas exchange, leading to gradual, worsening dyspnea.
-
A is incorrect: Pleuritic pain is typical of pleural disease or infection.
-
B is incorrect: Hemoptysis may occur in cavitary or endobronchial tumors but is not typical of lymphangitic spread.
-
D is incorrect: Hoarseness is associated with recurrent laryngeal nerve involvement.
Q4. What clinical scenario should raise suspicion for this diagnosis?
A) Febrile illness with productive cough
B) Recurrent pneumonia in a young adult
C) Non-resolving cough and weight loss in a 65-year-old
D) New-onset asthma in a child
Correct Answer: C) Non-resolving cough and weight loss in a 65-year-old
-
Explanation: Constitutional symptoms and chronic cough in an older adult are red flags for malignancy.
-
A is incorrect: This is more consistent with acute bronchitis or pneumonia.
-
B is incorrect: Suggests immunodeficiency or aspiration rather than cancer.
-
D is incorrect: Typical of childhood reactive airway disease, not malignancy.
Radiology
Q5. Which CT finding is most specific for lymphangitic carcinomatosis?
A) Cavitating nodule
B) Smooth interlobular septal thickening
C) Ground-glass opacities
D) Tree-in-bud nodules
Correct Answer: B) Smooth interlobular septal thickening
-
Explanation: Smooth septal thickening along bronchovascular bundles is the hallmark of lymphangitic tumor spread.
-
A is incorrect: Cavitating nodules suggest necrosis, infection, or squamous cell carcinoma.
-
C is incorrect: Ground-glass changes are nonspecific and seen in infection, hemorrhage, or early fibrosis.
-
D is incorrect: Tree-in-bud pattern suggests infectious bronchiolitis.
Q6. What is the most appropriate next step after identifying this pattern on CXR?
A) Start steroids
B) Order CT chest with contrast
C) Begin empiric antibiotics
D) Schedule bronchodilator testing
Correct Answer: B) Order CT chest with contrast
-
Explanation: CT is essential to confirm the diagnosis, evaluate extent of disease, and guide biopsy.
-
A is incorrect: Steroids may worsen undiagnosed infections or malignancies.
-
C is incorrect: Antibiotics are inappropriate without evidence of infection.
-
D is incorrect: Pulmonary function testing is not diagnostic here.
Q7. What role does PET/CT play in management of this case?
A) Differentiates between bacterial and viral infection
B) Measures lung volume
C) Confirms EGFR mutation
D) Staging and metabolic assessment
Correct Answer: D) Staging and metabolic assessment
-
Explanation: PET/CT identifies metabolic activity, assesses nodal and metastatic disease, and helps biopsy planning.
-
A is incorrect: PET/CT is not used for differentiating infections.
-
B is incorrect: Lung volume is assessed via spirometry or CT volumetry.
-
C is incorrect: EGFR mutations are confirmed via molecular testing, not PET.
5. Memory Image
Lymphangitis Carcinomatosa.
Crab Devil in the Lung Spreading Evil Into the Lymphatics
Crab Devil in the Lung Spreading Evil Into the Lymphatics
TheCommonVein.com Ashley Davidoff MD Artistic rendering of an AI Image (140499.lymphangitis carcinomatosa)