بسم الله الرحمن الرحيم

1. بسم الله الرحمن الرحيم

2. ROLE OF HELICAL CT IN ASSESSEMENT OF ABDOMINAL EXTRA-NODAL NHL

3. Lymphoma was considered a tumor of lymphoid system, but now it’s defined as a solid tumor of immune system. • Lymphoma may originate in any organ , shows different pathologic features, clinical behaviour & prognosis.

4. In Egypt, lymphoma comprises 10% of all malignancies. • NHL constitutes 69% (70% nodal, 30% extra nodal). • In USA and Europe, lymphoma represents the 5th common type of cancer with increasing incidence by about 4% annually.

5. ETIOLOGY

6. The exact etiology of lymphoma has not been identified, yet it’s thought to be associated with chronic antigenic stimulation.

7. (1)INHERITED SYNDROMES: Several rare but well defined inherited conditions known to be associated with NHL, these include: * ataxia telangiectasia * Wiskott-Aldrich * Bloom’s * Chediak-Higashi syndromes

8. (2)ALTERED IMMUNITY: a) Immunodeficiency duo to past medical history: excess risk of NHL in patients with organ transplantation consistent with immunosuppressive regimen. b) Viral immunosuppression: * risk of lymphoma in HIV +ve is about 100-fold greater than in general population.

9. *Role of EBV in Burkett's lymphoma is also well recognized. *Recently, HCV is thought to be a lymphotropic virus which may play a role in the increasing NHL rate in Egypt.

10. (3) OCCUPATIONAL LINKS: • Contrary to altered immunity, occupational links cause far smaller risk mostly related to agriculture. • Many studies demonstrated statistical excess of NHL in farmers.

11. CLASSIFICATION OF LYMPHOMA

12. Malignant lymphoma was first documented by Thomas Hodgkin’s. • Large number of classification systems were described. • The first classification gained wide acceptance was proposed by Henry Rappaport.

13. REAL classification was proposed in 1994 that widely applied now in most cancer institutes. • It depends on specific factors such as morphology, phenotyping, genotyping & clinical aspect. • Recently, WHO classification is proposed to establish a general & uniform scheme for lymphoma

14. EXTRA-NODAL LYMPHOMA

15. Lymphoma considered extra-nodal if it presents with the main bulk of the disease in an extra-nodal site. • Most of extra-nodal lymphoma are of NHL type.

16. GIT LYMPHOMAS • GIT is the most frequent site affected by NHL accounting for about 1/3 of all extra-nodal NHLs. • The stomach is the most frequent site followed by small intestine. • Histopathologic subtypes include MALT, IPSID, EATC lymphomas.

17. Hepatic lymphoma • Primary hepatic NHL is rare. • 80% of cases are of B-cell type. • it’s usually related to immunologic states like AIDS, organ transplantation & chronic active hepatitis.

18. Splenic lymphoma • Primary splenic lymphoma accounts for 1% of NHL. • Usually presents as splenomegaly or hypersplenism. • Subtypes include small cell tumor, large cell tumor of diffuse histocytic type or mixed cell type.

19. Renal lymphoma • Kidney is one of common sites of lymphomatous spread in disseminated disease, however primary renal lymphoma is very rare.

20. Pancreatic lymphoma • Primary pancreatic lymphoma is rare accounts for 1-3% of all pancreatic malignancies affecting age group ] 60 y. • It’s mostly of large cell histocytic or mixed cell type.

21. Adrenal lymphoma • primary adrenal lymphoma is rare & may be bilateral. • Presenting symptoms usually related to the mass effect. • Both B-cell & T-cell has been reported

22. CT Appearance Of Abdominal Extra-nodal Lymphoma

23. GASTRIC LYMPHOMA (1) Represents 5% of gastric malignancies. (2) It shows variety of radiological patterns: - One or multiple submucosal nodules. - Discrete mass. - Large ulcerating mass similar to adenocarcinoma. -Gastric wall thickening is the leading sign of CT, it affects entire stomach in 50% of cases

24. (3)Lesion usually has a homogeneous low attenuating pattern, however non uniform hypodense areas of necrosis, Hge, or infarction may be seen. (4)Finding of differentiation with adenocarcinoma includes:

25. 1- wall thickening is more extensive with lymphoma. 2- preserved fat planes is more common with lymphoma. 3- lymphoma rarely cause outlet obstruction 4- lymphadenopathy is bulkier with lymphoma & involves groups below renal hilum.

26. Gastric lymphoma. Persistent gastric wall thickening (S). Enlarged spleen and an enlarged Lt. gastric lymph node (arrow)

27. SMALL INTESTINE • It follows the stomach as the most common focus of extra-nodal NHL • 2/3 of cases occur in distal ileum • It appears as intramural polypoidal mass, multiple nodules, or segmental infiltration • It tend to be homogeneous with moderate contrast enhancement • Low dense area of necrosis, fluid density or air collection may be seen

28. Acute intestinal obstruction may be the first presentation, it’s usually 2ry to intussusception rather than constriction. • In contrast, lymphoma may slough in small intestine causing aneurysmal dilatation. • Mesentery may be involved either by discrete mesenteric lymphadenopathy or by direct exophytic extension.

29. wide spread thickening of the small-intestine wall (arrows), with adenopathy (n) in the adjacent mesentery.

30. COLONIC LYMPHOMA • 6-12% of GIT lymphomas • CT features include either a single focal mass often cecal resembling adenocarcinoma, or multiple small to large colonic nodules

31. Features of differentiation include: • Striking mural thickening of 5 cm or more • Homogeneous soft tissue lesion without areas of lower attenuation or calcification with low range of contrast enhancement • Striking regional and distal lymphadenopathy

32. intestinal NHL. Marked circumferential thickening of colonic wall that shows aneurysmal dilatation & exophytic component

33. SPLENIC LYMPHOMA • commonest malignancy of the spleen • patterns of involvement include: • Homogeneous enlargement • Miliary masses less than 5 mm • Multiple masses of variable size 1-10 cm • Large solitary mass more than 10 cm

34. CT mirrors variety of path. features • the solitary mass & multifocal lesions measuring 1cm or more are easy detected by CT • After IV contrast, these lesions usually enhance minimally and appear hypodense. Rarely a rim of contrast enhancement may be seen

35. Irregular cystic areas of necrosis may be seen in CT in case of large lesions • Calcification in splenic lymphoma may be seen after treatment • Reported accuracy of CT as a predictor of splenic involvement by lymphoma is rather low ranging from 58-65 %

36. Different cases of splenic lymphoma

37. HEPATIC LYMPHOMA • Most cases of hepatic lymphoma are secondary. • 1ry lymphoma is very rare

38. Grossly 1ry hepatic lymphoma usually solitary mass lesion, while in 2ry lymphoma, involvement is diffuse either miliary or multiple masses of low attenuation • Many studies reported that CT has been disappointing in hepatic lymphoma even in detectable lesions as they presented with non specific pattern

39. Hepatic lymphoma: Multiple hypodense focal lesions

40. RENAL LYMPHOMA • It’s usually not clinically evident & detected during imaging evaluation of a case of lymphoma

41. Grossly, several patterns may be seen: • Direct spread from retroperitoneal lymphoma masses • Multifocal • Solitary mass (not common) • Diffuse enlargement of both kidneys without discrete masses

42. In pre-contrast CT, lymphoma lesion is usually homogeneous isodense or slightly hyperdense • In post IV contrast CT: the lesions are of lower attenuating value than renal parenchyma

43. Treated Spine lymphoma under follow up shows: A: large hypodense Rt. Renal focal lesion. B: multiple smaller focal lesions seen distally C: the lesions are resolved after Cth

44. ADRENAL LYMPHOMA • Reported in 1-4% in patients being followed up for lymphoma • Adrenal lymphoma commonly seen as a part of disseminated disease • It’s bilateral in one third of cases

45. On CT usually large mass is seen altering the shape of the gland. • Mild to moderate enhancement is seen after IV contrast injection. • The lesions are often heterogenous with low attenuation areas.

46. Adrenal lymphoma. Pre- & post- contrast: bilateral lobulated adrenal masses shows heterogeneous mild enhancement. The patient was addisonian.

47. PANCREATIC LYMPHOMA • Can be confused with primary pancreatic neoplasm • Lymphoma is usually larger in size and associated with regional and distal lymphadenopathy

48. Pancreatic lymphoma: A: before treatment B: After 10 years, no evidence of disease

49. ROLE OF CT IN STAGING AND FOLLOW UP OF ABDOMINAL LYMPHOMA

50. The staging and follow-up of a case of abdominal lymphoma are the most important item for which abdominal CT become a routine investigation in these cases