Lung tumor
Other carcinoma
Metastatic tumors to lung

Author: Roseann Wu, M.D. (see Authors page)
Deputy Editor in Chief Review: Debra Zynger, M.D.

Revised: 5 September 2018, last major update February 2018

Copyright: (c) 2003-2018, PathologyOutlines.com, Inc.

PubMed Search: Metastatic lung tumor [title]

Cite this page: Wu, R. Metastastic tumors to lung. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/lungtumormetastases.html. Accessed October 15th, 2018.
Definition / general
  • Lung is a common site of metastases; usually multiple, bilateral, sharply outlined, rapidly growing, more pleomorphic and necrotic than lung primaries
  • May appear as multiple discrete nodules in periphery of lung or as lymphangitic carcinomatosis (peribronchial and perivascular patterns via lymphatics)
  • Rarely appear as intralymphatic microscopic foci that cause pulmonary hypertension
  • Metastases can also be from other lung primaries (Am J Surg Pathol 2009;33:1752)
Essential features
  • Lung is a common site of metastatic disease and may be the first or only site of metastatic involvement
  • Lung metastases are generally multiple, well circumscribed and tend to grow rapidly
  • A history of malignancy is helpful in determining the primary site but a panel of immunohistochemical stains can help support the diagnosis
ICD-10 coding
  • C78.00 Secondary malignant neoplasm of unspecified lung
  • C78.01 Secondary malignant neoplasm of right lung
  • C78.02 Secondary malignant neoplasm of left lung
Epidemiology
  • In autopsy studies, 20 - 50% of patients with malignancy had lung metastasis (Cancer 1981;47:2595)
Sites
  • Generally peripheral lung but can also be endobronchial
Pathophysiology
Etiology
  • Mostly hematogenous or lymphogenous spread from primary site
Clinical features
  • Usually asymptomatic or may present with nonspecific cough, chest pain, hemoptysis, spontaneous pneumothorax (J Surg Oncol 2014;109:42)
Diagnosis
  • Typically detected by imaging, specifically CT scans
  • Confirmation by cytologic or histologic sampling
Radiology description
  • CT scans are preferred modality
  • Single or multiple, peripheral, well circumscribed nodule(s)
  • Limited detection of subcentimeter disease
Radiology images

Images hosted on PathOut server:

Images contributed by Fulvio Lonardo, M.D.

Pancreas: adenocarcinoma



Images hosted on other servers:
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Malignant melanoma
shows pulmonary
nodules
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Multiple round nodules and masses in both lungs

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Cannonball lung metastases in patient with colon cancer

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Multiple lung metastases

Prognostic factors
  • Clinical variables associated with prolonged survival after lung metastasectomy in colorectal cancer patients
    • Prolonged disease free interval between primary tumor and metastasis, normal prethoracotomy carcinoembryonic antigen, absence of thoracic node involvement and single pulmonary lesion (Ann Surg Oncol 2013;20:572)
  • Complete resection and longer disease free interval > 6 months associated with better survival (Surg Oncol 2012;21:237)
Case reports
Treatment
  • Chemotherapy, immunotherapy, other systemic therapy
  • Criteria for pulmonary metastasectomy: primary site of disease controlled, complete resection of lung metastasis feasible, patient able to tolerate procedure, no better alternative treatments (J Surg Oncol 2014;109:42)
  • Stereotactic body radiation therapy (SBRT) and radiofrequency ablation (RFA) may be considered for small, solitary, peripheral tumors
Gross description
    Patterns associated with specific primaries
  • Central cavitation: colonic adenocarcinoma, leiomyosarcoma, squamous cell carcinoma of upper aerodigestive tract
  • Intrabronchial masses: breast, colon, kidney
  • Lymphangitic carcinomatosis: breast, choriocarcinoma, pancreas, prostate, stomach
  • Nodular metastases: breast, GI, kidney, melanoma, sarcoma
  • Tumor emboli: breast, choriocarcinoma, liver, stomach
Gross images

Images hosted on PathOut server:

Images contributed by Roseann Wu, M.D.
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Lung with metastatic tumor



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Multiple tumor nodules

Microscopic (histologic) description
  • Dependent on site of origin (colorectal cancer, bone and soft tissue sarcoma, renal cell carcinoma, melanoma, head and neck tumors, germ cell tumors and many others)
  • Evidence for breast metastasis over lung primary: comedonecrosis, solid nests, trabecular architecture, cribriform growth pattern (Am J Clin Pathol 2009;131:122)
Microscopic (histologic) images

Images hosted on PathOut server:

Images contributed by Roseann Wu, M.D., Debra Zynger, M.D.
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Metastatic colon CA to lung 25x (R.W.)

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Clear cell renal
cell carcinoma
metastatic to lung (D.Z.)
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Prostatic
adenocarcinoma
metastatic to lung (D.Z.)
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Testicular germ
cell tumor (teratoma)
metastatic to lung (D.Z.)


Image contributed by Nasir Uddin, M.D. - COW #318, Fulvio Lonardo, M.D.
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Jaw: Ameloblastoma
metastatic to lung (N.U.)

Pancreas: adenocarcinoma (F.L.)


Cytology images

Images hosted on PathOut server:

Images contributed by Roseann Wu, M.D.
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Metastatic renal cell carcinoma to lung DiffQuik 400x



Images hosted on other servers:

Bladder, urothelial carcinoma

Positive stains
Negative stains
  • TTF1 and NapsinA may be helpful to exclude primary lung adenocarcinoma
Differential diagnosis
  • Primary lung carcinoma: acini, lepidic growth, nuclear pseudoinclusions, central scar (Am J Clin Pathol 2009;131:122)
  • Inflammatory nodule or benign neoplasm
Board review question #1
    For which malignancy is pulmonary metastasectomy most commonly performed and reported?

  1. Colorectal cancer
  2. Germ cell tumors
  3. Melanoma
  4. Osteosarcoma
  5. Renal cell carcinoma
Board review answer #1
A. Colorectal cancer (Cancer 2015;121:747)