Transplant-associated penile Kaposi sarcoma managed with single agent paclitaxel chemotherapy: a case report

Transplant-associated Kaposi's sarcoma in a kidney allograft: a case report

Kaposi's sarcoma (KS) is a disease that is not widely known among the general public, but has a high prevalence among organ transplant recipients. Here, we present a rare case of intragraft KS after kidney transplantation. A 53-year-old woman who had been on hemodialysis due to diabetic nephropathy underwent deceased-donor kidney transplantation on December 7, 2021. Approximately 10 weeks after kidney transplantation, her creatinine level increased to 2.99 mg/dL. Upon examination, ureter kinking was confirmed between the ureter orifices and the transplanted kidney. As a result, percutaneous nephrostomy was performed, and a ureteral stent was inserted. During the procedure, bleeding occurred due to a renal artery branch injury, and embolization was performed immediately. Subsequently, kidney necrosis and uncontrolled fever developed, leading to graftectomy. Surgical findings revealed that the kidney parenchyma was necrotic as a whole, and lymphoproliferative lesions had formed diffusely around the iliac artery. These lesions were removed during graftectomy, and a histological examination was performed. The kidney graft and lymphoproliferative lesions were diagnosed as KS based on a histological examination. We report a rare case in which a recipient developed KS in the kidney allograft as well as in adjacent lymph nodes.

Penile osteosarcoma

Introduction

Extraskeletal osteosarcoma arising in the penis is exceedingly rare and its major differential diagnosis is sarcomatoid carcinoma.

Case presentation

A 19-year-old patient noticed a deep nodule in the dorsal side of the penis 2 years before this presentation. No skin lesions were noted until recent ulceration. In both biopsy and penectomy specimen, atypical mononuclear cells were diffusely positive for SATB2 (a marker of osteoblastic differentiation), CD99 and vimentin. These cells were negative for pan-keratin, SOX10, S100, EMA, GATA3 and CD68 was expressed only in multinucleated giant (osteoclast-like) cells. Few areas suggestive of osteoid production were noted.

Conclusion

In high-grade sarcomas, including in the penis, SATB2 staining may be useful to identify extraskeletal osteosarcoma.

Case Report: Metagenomic Next-Generation Sequencing Can Contribute to the Diagnosis and Treatment of Disseminated Visceral Kaposi Sarcoma Following Allogeneic Haematopoietic Stem Cell Transplantation

Disseminated visceral Kaposi sarcoma (KS) following allogeneic haematopoietic stem cell transplantation (HSCT) is a rare but life-threatening posttransplant complication. A suitable management strategy for disseminated KS involvement in transplant patients is unclear. Here, we reported a patient who developed disseminated visceral KS following HSCT, which was the first detailed report documenting the relationship among KS development, delayed immune reconstitution, and HHV-8 DNA levels by metagenomic next-generation sequencing (mNGS). The HHV-8 viral load peaked at 2071 sequence reads with an absolute lymphocyte count of 0.17×10⁹/L on day +242. On day +536, the HHV-8 viral load became undetectable, with an absolute lymphocyte count of 1.06×10⁹/L and the KS disappearance. HHV-8 load in blood detected by mNGS may be used as an early prediction marker for KS, a guide for early withdrawal of immunosuppression, and a tool to monitor KS treatment response in the setting of HSCT, especially in patients with CMV-seropositive or graft failure postengraftment. Through whole-exome sequencing, we explored the molecular mechanism underlying the patient’s longer latency of haematopoietic or immune reconstitution and recurrent infections. Germline mutations in the FANCI and RAD51 genes might impair the patient’s DNA repair ability, leading to a degree of immunodeficiency and tumour susceptibility. We strongly recommended evaluating the clinical history of the donor and investigating whether there were possible germline mutations suspected for immunodeficiency or familial neoplasms. Disseminated visceral KS patients could likely benefit from chemotherapy, especially if the disease appears to be aggressive.

Human herpesvirus 8 and Kaposi sarcoma: how should we screen and manage the transplant recipient?

PURPOSE OF REVIEW

HHV-8-associated diseases are rare but potentially fatal in transplant recipients. Important differences exist in the distribution of HHV-8 seroprevalence, which might contribute to the lack of uniform approach to HHV-8. The aim of this review was to discuss recent updates in screening and management of HHV-8 after transplant.

RECENT FINDINGS

Increasing attention has been given to the nonmalignant but potentially fatal inflammatory syndrome caused by HHV-8 in solid organ transplant (SOT) recipients. At-risk groups include HHV-8-IgG D+/R- transplant and HHV-8-positive recipients. Severe cases of donor-derived HHV-8 disease, mainly Kaposi sarcoma, frequently without skin involvement and some diagnosed at autopsy, highlight the need to increase clinicians' awareness, to implement effective preemptive strategies and to perform rapid diagnosis. In HSCT setting, HHV-8-associated disorders are very rare.

SUMMARY

Identification of SOT recipients at risk through reliable serology is warranted and the utility of preemptive management and HHV-8-DNA monitoring should be studied. Clinicians should be aware of severe nonmalignant disorders and of early post-SOT Kaposi sarcoma cases with lymph node or transplanted organ involvement in order to provide prompt diagnosis and treatment. No screening for HHV-8 is warranted after HSCT but rapid diagnosis and reduction of immunosuppression remain fundamental.