• Staging a lymphoma of the stomach or bowel: A lymphoma that starts in the stomach or bowel is staged by how deep it goes into the wall and how far along the lymph node chain it has travelled, not only by how many node regions are involved.
• Prognostic Index for T-cell lymphoma (PIT): A four-item score that estimates the outlook in nodal T-cell lymphoma, built because the index used for B-cell lymphoma separated these patients poorly.
• Stem cell transplant in lymphoma: what it is still for: An autologous transplant is very high-dose chemotherapy followed by the patient's own stored stem cells to rescue the bone marrow.
• Nodal and extranodal lymphoma: A lymphoma that starts in a lymph node is called nodal; one that starts in an organ is called extranodal.
• Endoscopy (EGD, EUS, ERCP): Looking inside a hollow organ with a camera on a flexible tube, taking biopsies and sometimes treating on the spot.
• The two lymphoma classifications of 2022 (WHO-HAEM5 and ICC): Since 2022 there have been two reference classifications of lymphoma rather than one, published within months of each other by overlapping groups of experts.
• The lymphoma regimen alphabet: R-CHOP, pola-R-CHP, DA-EPOCH-R, ABVD, BEACOPP and the rest: Lymphoma treatment is written in acronyms, one letter per drug.

Diagnosis, and the coeliac disease behind it: The diagnosis is often made on bowel resected as an emergency for perforation or obstruction. Where there is time, it is made at endoscopy with biopsies of the small bowel. Coeliac disease is confirmed or newly diagnosed at the same time, and the rest of the family is offered testing. Staging uses the gastrointestinal system that counts depth and node involvement, and imaging of the whole abdomen matters because disease is often multifocal.

Biomarker results to ask for: Coeliac disease, established or newly discovered at the time of the lymphoma, which is part of the definition, A T-cell phenotype that is most often negative for both CD4 and CD8, with CD30 often positive, Pleomorphic large or medium-sized cells against a prominent inflammatory background, which separates it from the monomorphic intestinal lymphoma, Gains of 9q34 and loss of 16q12, with mutations of the JAK-STAT pathway, commonly JAK1 and STAT3, Absence of Epstein-Barr virus, Nutritional state, which determines what treatment is possible.

Scans and tests linked to this cancer: FDG PET, Histopathology & immunohistochemistry.

Bring copies of scan reports, pathology and blood results, and a list of every medicine and supplement.

• Nutrition and the surgical risk, which come first: Most patients are malnourished before the lymphoma starts, because the coeliac disease has been damaging the bowel, and the bowel is at risk of perforating during treatment. Nutritional assessment and support, often intravenous, and early involvement of a surgeon are part of the treatment rather than an afterthought, and they determine what chemotherapy is possible. A strict gluten-free diet is continued throughout. (The lymphoma regimen alphabet: R-CHOP, pola-R-CHP, DA-EPOCH-R, ABVD, BEACOPP and the rest, Peripheral T-cell lymphomas (including cutaneous T-cell lymphoma))
• Systemic treatment: In the population-based series from northern England and Scotland, conventional anthracycline-based chemotherapy with or without surgery gave a median progression-free survival of 3.4 months and overall survival of 7.1 months in 54 patients. From 1998 the same group gave patients fit enough for it ifosfamide, etoposide and epirubicin alternating with methotrexate, followed by an autologous stem cell transplant; in 26 patients treated that way, five-year progression-free survival was 52 per cent and overall survival 60 per cent. That is a comparison against a historical group from the same region rather than a randomised trial, and it is the best evidence this disease has. A clinical trial is a reasonable first choice. (Ifosfamide, Etoposide, Methotrexate, Autologous stem cell transplant (high-dose therapy), Stem cell transplant in lymphoma: what it is still for, The lymphoma regimen alphabet: R-CHOP, pola-R-CHP, DA-EPOCH-R, ABVD, BEACOPP and the rest)

From the standard of care recorded for this cancer; which apply depends on your stage and biomarkers. Ask which the team recommends and why.