Indian Journal of Radiology and Imaging Indian Journal of Radiology and Imaging

LETTER TO EDITOR
Year
: 2002  |  Volume : 12  |  Issue : 1  |  Page : 132--133

Posttransplant lymphoproliferative disorder (PTLD) localized near the allograft mimicking a collection


MS Sandhu, N Kalra, R Sidhu 
 Department of Radiodiagnosis and Imaging, Postgraduate Institute of Medical Education and Research, Chandigarh-160012, India

Correspondence Address:
M S Sandhu
Department of Radiodiagnosis and Imaging, Postgraduate Institute of Medical Education and Research, Chandigarh-160012
India




How to cite this article:
Sandhu M S, Kalra N, Sidhu R. Posttransplant lymphoproliferative disorder (PTLD) localized near the allograft mimicking a collection.Indian J Radiol Imaging 2002;12:132-133


How to cite this URL:
Sandhu M S, Kalra N, Sidhu R. Posttransplant lymphoproliferative disorder (PTLD) localized near the allograft mimicking a collection. Indian J Radiol Imaging [serial online] 2002 [cited 2019 Oct 21 ];12:132-133
Available from: http://www.ijri.org/text.asp?2002/12/1/132/28432


Full Text

Sir,

Posttransplant lymphoproliferative disorder (PTLD) is a sequelae of chronic immunosuppression and affects approximately 1% of renal transplant cases [1]. PTLD represents a spectrum of abnormal proliferation of B-cells that ranges from polymorphic hyperplasia to monomorphic lesions which are indistinguishable from non-Hodgkin's lymphoma. There are no specific presenting symptoms and some patients may be entirely asymptomatic. It is important that the radiologist should have a high index of suspicion while imaging transplant patients as early detection of PTLD and timely institution of appropriate treatment could be life saving in this potentially fatal condition. We present one case of non - Hodgkin's lymphoma localized near the renal allograft which was a diagnostic dilemma because it mimicked a collection / abscess on ultrasound and computed tomography.

A 37-year-old male with end - stage renal disease underwent renal transplantation in November, 1999. He was maintained on triple drug immunosuppression (cyclosporine (CSA), azathioprine (AZA) and prednisolone). His immediate posttransplant period was uneventful but the course later on was complicated by repeated infections requiring frequent antibiotics. In July, 2000 the patient presented with fever, urinary tract infection and septicemia.

An ultrasound done in this patient revealed a well-defined hypoechoic lesion in relation to the posteromedial aspect of graft kidney which was interpreted as an organized collection/abscess [Figure 1]. A contrast - enhanced CT scan was subsequently done which revealed a homogenous attenuation localized lesion posteromedial to the allograft. It showed wall enhancement and central hypodensity [Figure 2]. There was no lymph node enlargement seen. There was no other focal lesion seen in the rest of the abdomen. The possibility of an infected collection/abscess was kept in view of the clinical features. A diagnosis of PTLD was not considered.

Subsequently the patient underwent a CT - guided fine needle aspiration cytology from the lesion which was noncontributory. He was taken up for laparotomy and possible abscess drainage. Intraoperatively there was a large mass with gritty feel behind the graft kidney. Peroperative frozen section showed necrotic tissue only. A biopsy was also obtained which showed non - Hodgkin's lymphoma, B-cell type. The immunosuppression was reduced and later on stopped in view of overwhelming sepsis and wound dehiscence and infection. The patient was being planned for chemotherapy. However his condition worsened and he died in September, 2000.

Starlz in 1968 [2] first discovered the existence of transplant associated lymphoproliferations. Penn instituted an informal registry of transplant tumors, located first in Denver and then in Cincinnati in the same year [3]. The term posttransplant lymphoproliferative disorder (PTLD) is used to refer to a spectrum of entities that merge into the histologic pattern of infectious mononucleosis on one hand and the histologic pattern of true non - Hodgkin's malignant lymphoma on the other. A strong association exists between PTLD and Epstein-Barr virus infection of the B-lymphocytes.

The chronic use of immunosuppressive agents to prevent allograft rejection increases the long-term risk of malignancy. A variety of neoplasms occur with increased frequency in solid organ transplant recipients including skin cancers, Kaposi's sarcoma, cervical and rectal carcinoma and lymphoma. Renal recipients have the lowest and heart/lung recipients the highest frequency of PTLD. The reported frequency is 1 % in renal transplant patients, 1 .8% in heart, 2.2% in liver and 4.6% in heart/lung transplant patients [1]. Higher immunosuppression is needed in case of allograft with higher frequencies of PTLD. The type of immunosuppression is not as important as its presence and intensity. The majority of patients have tumor onset within one year after transplant, which is the time of the most intense immunosuppression.

All the solid and hollow visceral abdominal organs can be involved in PTLD. Miller et al reported the transplanted kidney as the most common site of PTLD (47%) in renal transplant cases [4]. Kew et al found disease localized near the renal allograft in 10 of the 14 patients developing PTLD [5]. The imaging findings of PTLD are nonspecific. On ultrasound it is seen as a hypoechoic or mixed echogenicity mass lesion. On CT there is a non-enhancing or peripherally enhancing low attenuation mass lesion. Tumor growth in the region of renal hilum with ureter/vessel encasement has also been reported.

We conclude that a high index of suspicion for PTLD should be kept when imaging posttransplant renal patients. All intrarenal or pararenal mass lesions in these patients irrespective of their imaging features should be biopsied to exclude/confirm the diagnosis of PTLD.

References

1Nalesnik MA, Makowka L, Starzl TE et al. The diagnosis and treatment of posttransplant lymphoproliferative disorder. Curr Probl Surg 1988; 25: 371-462.
2Starlz TE. Discussion of Murray JE, Whilson RE, Tilney NL, et al. Five years experience in renal transplantation with immunosuppressive drugs: Survival, function, complications and the role of lymphocyte depletion of thoracic duct fistula. Ann Surg 1968; 168:416-435.
3Penn I. Malignancy associated with immunosuppressive or cytotoxic therapy. Surgery 1978; 83: 492-502.
4Miller WT Jr, Siegel SG, Montone KT. Posttransplantation lymphoproliferative disorder : changing manifestation of disease in a renal transplant population. Crit Rev Diagn Imaging 1997; 36: 569-585.
5Kew CE, Lopez - Ben R, Smith JK, et al. Posttransplant lymphoproliferative disorder localized near the allograft in renal transplantation. Transplantation 2000; 69: 809-814.