To identify factors that might improve the prognosis of adult T-cell leukemia/lymphoma (ATL), we reviewed data on 47 autopsied cases of ATL with reference to the complications and cause of death. The primary cause of death was respiratory insufficiency due to pulmonary infection. Respiratory insufficiency was also attributed to the diffuse alveolar damage and pulmonary fibrosis resulting from chemotherapy given and oxygen. About 90% of the cases had infections with one or more pathogens. Cytomegalovirus (CMV) was the most frequent pathogen involved in 35/47 (74.5%) while fungal infections were also commonly seen in 25 of the 47 cases (53.2%). Of these, 17 (70%) had pulmonary aspergillosis. Other neoplasias were present in 10 of the 47 cases, while hypercalcemia was evident in 21 patients. These findings suggest that the prevention and treatment of nosocomial infections and of drug-induced pulmonary toxicity may improve the prognosis and quality of life of ATL patients.

As opportunistic infections among human T-lymphotrophic virus type 1 (HTLV-1) carriers and patients with adult T-cell leukemia/lymphoma (ATL) pose a serious problem, it is necessary to clarify their clinical characteristics and outcomes in these patients. We retrospectively analyzed the clinical features and outcomes of opportunistic infections in 127 HTLV-1 carriers and 153 ATL patients between 2006 and 2016. The cumulative incidence rates of opportunistic infections among HTLV-1 carriers and ATL patients were 1.5% (2/127) and 6.5% (10/153), respectively. The etiology of opportunistic infections was as follows: fungal infections (3 cases), pneumocystis pneumonia, and cytomegalovirus (CMV) infections. Even after aggressive treatment, the prognosis of opportunistic infections was poor (50% of overall survival at 28 days). Regarding prognostic factors affecting the OS of opportunistic infections, higher SOFA scores (especially the respiratory subscore) and higher LDH values were identified by univariate analysis. Moreover, 3 out of 6 patients achieved spontaneous remission of ATL as the shortterm outcome after the development of opportunistic infection. However, 5 out of 6 surviving patients exhibited ATL progression or relapse after a median of 194 days (133-226) after contracting an opportunistic infection as the long-term outcome of ATL. In conclusion, opportunistic infections should be carefully followed among HTLV-1 carriers and ATL patients because of their aggressive clinical course and poor outcomes. Furthermore, early diagnosis and subsequent prompt treatment are necessary in clinical practice.

Backgrounds Therefore, reports on the risk of HTLV-1-related diseases in organ transplantation have increased in recent years, and the management of HTLV in renal transplantation remains a challenge. Patients and methods We retrospectively analyzed four HTLV-1-positive recipients or donors among 89 renal transplantation cases from 2006 to 2021. Results Among the four HTLV-1-positive recipients, two patients developed adult T cell leukemia/lymphoma (ATL) derived from recipients at approximately 3 years (1016 days and 1195 days) after renal transplantation. Case 1 developed lymphoma-type ATL (an extranodal primary cutaneous variant), including skin and pulmonary lesions. The patient achieved CR with FK tapering and CHOP therapy following cord blood stem cell transplantation. However, the patient died 101 days after ATL development because of a severe fungal infection. Case 2 developed acute-type ATL with an unusual phenotype of CD4+8+30+. The patient was treated with FK tapering and palliative therapy because of poor PS. Notably, in case 1, histopathological findings showed high numbers of PD-1-positive TIL cells in ATL, suggesting exhausted T cells and a correlation with the early onset of ATL. Furthermore, in Case 2, histopathological findings revealed CD 30 expression in ATL cells, suggesting the importance of CD 30 in ATL development. Importantly, case 2 showed typical driver mutations, including CCR4 truncation mutations of the C-terminal, TBL1XR1 mutation, and TP53 mutation in the splice site. Notably, our present study and our previous study on renal transplantation strongly indicated that two out of two and one out of 59 “recipient” positive cases developed ATL, respectively. Furthermore, our previous nationwide study 4 out of 10 “donor” positive cases developed HAM. These findings showed that ATL may be derived from HTLV-I+ recipient cells and HAM may be derived from HTLV-1+ donor cells, although the precise mechanism remains unknown. Conclusions Thus, early onset and rapid progression of ATL with poor outcomes should be considered in HTLV-1 endemic areas. Furthermore, immunological or genetic mechanisms may be related to the development of ATL after renal transplantation. We believe that the mechanism of onset of ATL after transplantation may be important when considering the immune environment of ATL itself.