This category includes following disorders:

• Enteropathy-associated T-cell lymphoma
• Indolent T-cell lymphoma of the gastrointestinal tract
• Indolent NK-cell lymphoproliferative disorder of the gastrointestinal tract
• Monomorphic epitheliotropic intestinal T-cell lymphoma
• Intestinal T-cell lymphoma, NOS

Enteropathy-associated T-cell lymphoma

Introduction:

• It is an aggressive primary intestinal T-cell lymphoma of intraepithelial lymphocytes, usually affecting small intestine

Epidemiology:

• Incidence: 0.14/1lac/year
• Median age- 57 years
• Accounts for <1% of all lymphomas
• Accounts for 25% of primary intestinal lymphomas
• M:F= 3:1

Etiology:

• Associated with celiac disease
• High association with HLA DQ2 and 8.

Clinical Features:

• Diarrhea
• Abdominal pain
• Weight loss
• Nausea, vomiting
• Bowel obstruction/ perforation

Investigations:

• Biopsy of lesion
  • Mass invades the wall of intestine
  • Tumor cells- Monomorphic, medium to large sized with round to angulated, vesicular nucleus. Prominent nucleoli. Cytoplasm is moderate to abundant, pale staining
  • Most show infiltration by inflammatory cells including histiocytes & eosinophils
  • Infiltration of the epithelium of individual crypts is seen
  • Adjacent mucosa may show enteropathy, comprising of villous atrophy, crypt hyperplasia, increased lamina propria lymphocytes & plasma cells and intra epithelial lymphocytosis
• Immunophenotyping
  • Positive – CD3, CD7, CD103, and Cytotoxic granule associated proteins, CD2, CD30
  • Negative - CD5, CD4
  • Variable- CD8, CD56
• Molecular studies:
  • HLA – DQA1.  0501 DQB1 – 0201 genotype
  • Clonal rearrangements of TCR genes
  • Complex segmental amplification of 9q31.3, del 16q31.3

Prognosis:

• Poor- Overall survival- 7 months
• Aggressive clinical course with high risk of intestinal recurrence

Pretreatment Work-up:

Same as PTCL-NOS

Treatment Plan:

• Follow guidelines of PTCL-NOS
• Surgery to remove the tumor
• Gluten free diet
  
   

Related Disorders:

• Monomorphic intestinal T cell lymphoma (Enteropathy associated T cell lymphoma type II)
  • Monomorphic small/ medium sized cells
  • Florid infiltration of intestinal crypt epithelium.
  • Most of the cases are CD3, CD8 and CD56 positive

Indolent T-cell lymphoma of the gastrointestinal tract

• Clonal T-cell proliferation characterized by the infiltration of the lamina propria by small mature lymphocytes lacking significant epitheliotropism
• Located in small bowel or colon
• Clinical features: chronic diarrhea, pain abdomen,vomiting, dyspepsia
• Indolent course, often chronic persistent or relapsing
• Response to chemotherapy is poor

Indolent NK-cell lymphoproliferative disorder of the gastrointestinal tract

(Lymphomatoid gastropathy)

• Clinical features: Usually asymptomatic
• Usually undergo spontaneous regression, but may develop recurrent new lesions
• Commonly involves stomach, small and large intestines

Monomorphic epitheliotropic intestinal T-cell lymphoma

• It is an aggressive primary intestinal T-cell lymphoma of intraepithelial T lymphocytes
• No association with Celiac disease is present
• Small intestine is involved
• Presents with abdominal symptoms (such as pain, bleeding) and weight loss.
• Bowel perforation or obstruction are common
• Aggressive clinical course
• Overall survival- 7 months
• Resistant to CHOP