Figure 1
Unenhanced CT abdomen
Lymphoma of the urinary system
SectionUroradiology & genital male imaging
Case TypeClinical Cases
AuthorsDr. Akshay Pendkar4; Dr. Shailesh Bhuriya4; Dr. H.P.Parekh, M.D., 2; Dr. Ketan Rathod, M.D.3; Dr. N. U. Bahri, M.D.1.
Connected authors
51 years, male
Clinical History
A 51-year-old male patient presented to the emergency room with a history of mild left flank pain since 6 months. He also complained of weight loss in the past few months. The patient was not admitted to the hospital for any medical problem prior to this visit.
Imaging Findings
Unenhanced CT abdomen revealed a large, relatively well-defined, lobulated, predominantly hyperdense lesion, involving almost the entire left kidney with maintenance of its reniform shape. Left renal staghorn calculus was also noted. (Fig 1)
On post-contrast venous phase, the renal lesion showed mild homogeneous enhancement. No evidence of internal necrosis was noted. (Fig 2a)
Similar characteristic soft tissue thickening was also noted along bilateral ureters up to the lower end and the urinary bladder. (Fig 2b, 2c, 2d)
On 1 hour delayed scan, contrast excretion was noted in the right kidney but was not noted in the left kidney. (Fig 3)
The above mentioned left renal lesion and soft tissue peri-ureteral thickening appeared hypointense on T2 weighted images with no evidence of necrosis within it. (Fig 4a, 4b)
Our diagnosis was confirmed by biopsy which revealed Non-Hodgkin's lymphoma.
On post-contrast venous phase, the renal lesion showed mild homogeneous enhancement. No evidence of internal necrosis was noted. (Fig 2a)
Similar characteristic soft tissue thickening was also noted along bilateral ureters up to the lower end and the urinary bladder. (Fig 2b, 2c, 2d)
On 1 hour delayed scan, contrast excretion was noted in the right kidney but was not noted in the left kidney. (Fig 3)
The above mentioned left renal lesion and soft tissue peri-ureteral thickening appeared hypointense on T2 weighted images with no evidence of necrosis within it. (Fig 4a, 4b)
Our diagnosis was confirmed by biopsy which revealed Non-Hodgkin's lymphoma.
Discussion
Lymphomatous involvement of kidneys, ureter and urinary bladder can be either primary or secondary. When it is a part of systemic lymphomatous disease, it is known as secondary lymphoma. Primary renal lymphoma is when there is no extra renal focus of lymphomatous involvement.
Incidence of primary renal lymphoma is rare, <1% of all the renal lesions [1]. Overall incidence of renal involvement in lymphoma in autopsy specimen is 34 % to 62%, but CT detects renal involvement in only 3-8 % [2].
Most of the lymphomas are B cell Non-Hodgkin’s lymphoma [2].
It is insidious in onset, therefore presents late in its course. Presenting complaints are flank pain, haematuria, abdominal lump or weight loss [3].
On imaging, lymphoma has five characteristic patterns [4]:
(A) Most common pattern is the appearance of multiple minimally enhancing (enhancement less than adjacent renal parenchyma) homogeneously hypodense / T2 hypointense masses ranging from 1-3 cm with minimal necrosis (bilateral > unilateral involvement). Associated retroperitoneal lymphadenopathy may be seen in up to 50% of the cases.
(B) Second most common pattern is the solitary homogeneously hypodense / hypoechoic / T2 hypointense mass with minimal enhancement.
(C) Third most common type is the contiguous retroperitoneal extension, here there is a large bulky retroperitoneal mass that completely encases the renal hilum with encasement of renal vessels which remain patent despite the bulky mass over it.
(D) Fourth most common pattern is peri-renal disease, here we can appreciate soft tissue thickening in peri-renal fat surrounding the kidney. This is commonly seen as the direct extension of retroperitoneal disease or trans-capsular spread of renal parenchymal disease.
(E) Sometimes it can present as diffuse infiltration of bilateral kidneys.
Atypical patterns include spontaneous haemorrhage, necrosis, heterogeneous attenuation, cystic transformation, and calcification [4].
Added advantage of MRI over CT includes excellent anatomic resolution, ability to detect extension of lesion into peri-nephric space more accurately, ability to detect small renal lesions without the need of contrast and lack of ionizing radiation [6]. However, CT remains the main investigation for evaluation of renal lesions.
Accurate diagnosis of the lymphomatous renal involvement is important since lymphoma is highly chemo-sensitive, so medical treatment is the treatment of choice with CHOP (cyclophosphamide, adriamycin, vincristine, prednisolone) - rituximab regimen showing near complete resolution. Thus, accurate diagnosis avoids unnecessary surgery [5].
Take home message:
Bulky masses involving kidney with maintenance of reniform shape showing mild enhancement with no internal necrosis should raise the possibility of lymphomatous involvement.
Incidence of primary renal lymphoma is rare, <1% of all the renal lesions [1]. Overall incidence of renal involvement in lymphoma in autopsy specimen is 34 % to 62%, but CT detects renal involvement in only 3-8 % [2].
Most of the lymphomas are B cell Non-Hodgkin’s lymphoma [2].
It is insidious in onset, therefore presents late in its course. Presenting complaints are flank pain, haematuria, abdominal lump or weight loss [3].
On imaging, lymphoma has five characteristic patterns [4]:
(A) Most common pattern is the appearance of multiple minimally enhancing (enhancement less than adjacent renal parenchyma) homogeneously hypodense / T2 hypointense masses ranging from 1-3 cm with minimal necrosis (bilateral > unilateral involvement). Associated retroperitoneal lymphadenopathy may be seen in up to 50% of the cases.
(B) Second most common pattern is the solitary homogeneously hypodense / hypoechoic / T2 hypointense mass with minimal enhancement.
(C) Third most common type is the contiguous retroperitoneal extension, here there is a large bulky retroperitoneal mass that completely encases the renal hilum with encasement of renal vessels which remain patent despite the bulky mass over it.
(D) Fourth most common pattern is peri-renal disease, here we can appreciate soft tissue thickening in peri-renal fat surrounding the kidney. This is commonly seen as the direct extension of retroperitoneal disease or trans-capsular spread of renal parenchymal disease.
(E) Sometimes it can present as diffuse infiltration of bilateral kidneys.
Atypical patterns include spontaneous haemorrhage, necrosis, heterogeneous attenuation, cystic transformation, and calcification [4].
Added advantage of MRI over CT includes excellent anatomic resolution, ability to detect extension of lesion into peri-nephric space more accurately, ability to detect small renal lesions without the need of contrast and lack of ionizing radiation [6]. However, CT remains the main investigation for evaluation of renal lesions.
Accurate diagnosis of the lymphomatous renal involvement is important since lymphoma is highly chemo-sensitive, so medical treatment is the treatment of choice with CHOP (cyclophosphamide, adriamycin, vincristine, prednisolone) - rituximab regimen showing near complete resolution. Thus, accurate diagnosis avoids unnecessary surgery [5].
Take home message:
Bulky masses involving kidney with maintenance of reniform shape showing mild enhancement with no internal necrosis should raise the possibility of lymphomatous involvement.
Differential Diagnosis List
Lymphoma involving kidney, ureter and urinary bladder.
Renal cell carcinoma
Metastases to kidney
Retroperitoneal fibrosis
Final Diagnosis
Lymphoma involving kidney, ureter and urinary bladder.
References
[1] Francualdo Barreto; Marcos F. Dall’Oglio; Miguel Srougi; (2006) Renal lymphoma, atypical presentation of a renal tumor. International braz j urol 32 (2) (PMID: 16650297)
[2] Sean R.Sheeran1 and Steven K.Sussman1 (1998) Renal Lymphoma: Spectrum of CT Findings and Potential Mimics. AJR 171(4):1067-72. (PMID: 9762998)
[3] Bruce A. Urban, MD, and Elliot K. Fishman, MD (2000) Renal Lymphoma: CT Patterns with Emphasis on Helical CT. Radiographics 20(1) (PMID: 10682781)
[4] Sheila Sheth, MD, Syed Ali, MD, and Elliot Fishman, MD (2006) Imaging of Renal Lymphoma: Patterns of Disease with Pathologic Correlation. Radiographics 26(4) (PMID: 16844939)
[5] F. Vázquez-Alonso,1 I. Puche-Sanz,1 C. Sánchez-Ramos,2 J. Flores-Martín,1 J. Vicente-Prados,1 and J. M. Cózar-Olmo (2012) Primary Renal Lymphoma: Long-Term Results of Two Patients Treated with a Chemotherapy + Rituximab Protocol. Hindawi 726424 (PMID: 22997596)
[6] Arthur D. Smith, Gopal Badlani, Glenn Preminger, Louis Kavoussi (2012) Smith's textbook of Endourology 1361
Case information
| URL: | https://eurorad.org/case/15242 |
| DOI: | 10.1594/EURORAD/CASE.15242 |
| ISSN: | 1563-4086 |
License
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Figure 2
Post-contrast venous phase abdomen
On post-contrast venous phase, the renal lesion showed mild homogeneous enhancement. No evidence of internal necrosis was noted. (red arrow)
Similar characteristic soft tissue thickening was also noted along bilateral ureters up to lower end (red arrows).
Coronal section demonstrating bulky left renal mass (yellow arrow), soft tissue thickening around ureter (red arrows), within urinary bladder (blue arrow).
Soft tissue thickening within urinary bladder (yellow arrow).
Figure 3
Delayed scan
On 1-hour delayed scan, contrast excretion was noted in right kidney (yellow arrow) but was not noted in left kidney (red arrow).
Figure 4
MRI abdomen T2-weighted axial image
Unenhanced CT abdomen
A large, relatively well-defined, lobulated, predominantly hyperdense lesion (red arrow), involving almost entire left kidney with maintenance of its reniform shape.
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Left renal staghorn calculus was also noted (yellow arrow).
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Post-contrast venous phase abdomen
On post-contrast venous phase, the renal lesion showed mild homogeneous enhancement. No evidence of internal necrosis was noted. (red arrow)
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Similar characteristic soft tissue thickening was also noted along bilateral ureters up to lower end (red arrows).
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Coronal section demonstrating bulky left renal mass (yellow arrow), soft tissue thickening around ureter (red arrows), within urinary bladder (blue arrow).
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Soft tissue thickening within urinary bladder (yellow arrow).
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Delayed scan
On 1-hour delayed scan, contrast excretion was noted in right kidney (yellow arrow) but was not noted in left kidney (red arrow).
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
MRI abdomen T2-weighted axial image
The above mentioned left renal lesion appeared hypointense on T2 weighted images with no evidence of necrosis within it (red arrow).
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
The above mentioned soft tissue peri-ureteral thickening appeared hypointense on T2 weighted images with no evidence of necrosis within it (yellow arrows).
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.
Department of Radio diagnosis, M.P. Shah Government Medical College, Guru Gobind Singh Government Hospital, Jamnagar, Gujarat, India.