Undifferentiated carcinoma

Editorial Board Member: Catherine E. Hagen, M.D.
Deputy Editor-in-Chief: Raul S. Gonzalez, M.D.
Ryan Kendziora, M.D.
Rondell P. Graham, M.B.B.S.

Last author update: 27 April 2021
Last staff update: 21 May 2021

Copyright: 2021,, Inc.

PubMed Search: Esophagus - Undifferentiated carcinoma [TIAB]

Ryan Kendziora, M.D.
Rondell P. Graham, M.B.B.S.
Page views in 2021: 1,116
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Cite this page: Kendziora R, Graham RP. Undifferentiated carcinoma. website. Accessed December 3rd, 2022.
Definition / general
  • Rare and aggressive esophageal carcinoma
  • Histologically characterized by sheets of cells with high grade features, frequent rhabdoid appearance and monotony
Essential features
  • Neoplastic cells appear high grade with frequent rhabdoid appearance
  • Background Barrett esophagus with or without dysplasia may be identified
  • May have limited or absent expression of pancytokeratins
  • Characterized by frequent loss of SMARCA4 or SMARCA2
  • Dismal prognosis with frequent recurrence or metastasis
ICD coding
  • ICD-O: 8020/3 - carcinoma, undifferentiated, NOS
  • ICD-11: 2B70.Y - other specified malignant neoplasms of esophagus
  • ICD-11: XH1YY4 - carcinoma, undifferentiated, NOS
  • M > F
  • Median age in seventh decade
  • Likely related to Barrett esophagus associated adenocarcinomas
  • Very rare: as low as 0.15% of esophageal carcinomas (Dis Esophagus 2009;22:1)
  • Distal esophagus
  • Gastroesophageal junction
  • Likely dedifferentiation / high grade progression of adenocarcinoma
  • Subset of cases has associated Barrett esophagus and Barrett associated dysplasia
  • Mutant p53 pattern by immunohistochemistry
  • Frequent loss of SMARCA4 or SMARCA2 by immunohistochemistry
  • Same as Barrett esophagus associated adenocarcinoma
Clinical features
  • Presentation similar to other esophageal cancers
    • Progressive dysphagia
    • Symptoms of gastroesophageal reflux disease
    • Unexplained weight loss (Hum Pathol 2015;46:366)
  • Typically locally advanced at diagnosis
  • Seen as exophytic mass on esophagogastroduodenoscopy
  • Confirmed by histology and immunohistochemistry
Prognostic factors
  • Poor prognosis overall: currently 20% 1 year survival rate
  • As many as 67% will have local recurrence or metastasis (Hum Pathol 2015;46:366)
Case reports
  • Neoadjuvant chemotherapy followed by esophagogastrectomy
  • Palliative care
Gross description
  • Exophytic mass
  • Raised edges
  • Central ulceration
  • Pushing border
Microscopic (histologic) description
  • Nests and sheets of cells
  • Cytology is high grade with large nuclei and high nucleus to cytoplasm ratio
  • Can have rhabdoid features
  • Sheets of necrosis
  • Lymphoepithelioma-like carcinoma a distinct subtype
    • Sheets of epithelioid cells surrounded by dense lymphoplasmacytic inflammatory infiltrate
  • Absence of identifiable signs of differentiation (adenocarcinoma, squamous cell carcinoma, neuroendocrine carcinoma)
Microscopic (histologic) images

Contributed by Rondell P. Graham, M.B.B.S.
Sheets of cells Sheets of cells

Sheets of cells

Low grade to high grade carcinoma Low grade to high grade carcinoma

Low grade to high grade carcinoma

Loss of SMARCA4 (BRG1) Loss of SMARCA4 (BRG1)

Loss of SMARCA4 (BRG1)

Positive stains
Negative stains
Sample pathology report
  • Esophagus, biopsy:
    • Undifferentiated carcinoma (see comment)
    • Comment: SMARCA4 loss is seen by immunohistochemistry.
Differential diagnosis
Board review style question #1

A patient undergoes esophagogastrectomy for a tumor of the distal esophagus. A representative hematoxylin and eosin photomicrograph of the lesion is shown. The tumor lacks any immunohistochemical signs of differentiation, including negativity for pancytokeratin, MelanA, synaptophysin, chromogranin and CD34. An esophageal carcinoma of this subtype is characterized by what immunophenotype?

  1. Keratin 7 expression
  2. Wild type p53
  3. Loss of SMARCA4 or SMARCA2
  4. Expression of Rb
Board review style answer #1
C. Loss of SMARCA4 or SMARCA2. This is an undifferentiated carcinoma of the esophagus.

Comment Here

Reference: Undifferentiated carcinoma
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