Kaposi sarcoma

Definition: Kaposi sarcoma is a multifocal HHV-8-driven vascular proliferation which does not show conventional features of malignancy—in particular, it may regress spontaneously.

Images

 Kaposi sarcoma

• https://twitter.com/bunn_belinda/status/796890548493815808
• https://twitter.com/phmckee1948/status/845560382362144768
• https://twitter.com/phmckee1948/status/865860247172395009
• https://twitter.com/IPenzhorn/status/1323995643757711365

 polypoid lesion : pyogenic granuloma-like Kaposi sarcoma (H&E, HHV-8).

• https://twitter.com/bunn_belinda/status/739550781729345537

 micronodular growth in Kaposi sarcoma

• https://twitter.com/bunn_belinda/status/742098640089546752

 promontory sign in Kaposi sarcoma

• https://twitter.com/bunn_belinda/status/742099733985042432

 anaplastic Kaposi sarcoma - palate. (HHV-8 nuclear signaling)

• https://twitter.com/bunn_belinda/status/873380830047031296

Synopsis

 spindle cells forming slit-like vascular spaces.
 extravasated red blood cells and hemosiderin deposition.
 IHC : HHV8 IHC+ (nuclear speckles)

Digital cases

 HPC:28 : Kaposi sarcoma
 UI:488 - cutaneous Kaposi sarcoma.
 JRC:10989 : Kaposi sarcoma.
 JRC:11011 : Kaposi sarcoma.
 Kaposi sarcoma of skin of the skin on Flick by ddkri

It shows relative sparing of certain tissues such as brain, kidney and skeletal muscle, is most often diploid, is very difficult to transplant/xenograft and does not appear to show any conventional pattern of metastasis.

Etiology

 Human herpesvirus-8 (HHV-8) infection is considered the initiating factor in all forms of Kaposi sarcoma (KS)

Cytogenetics

 No consistent abnormality

See also

 Tumors

• soft tissue tumors
  • vascular tumors

References

 Verschuren EW, Jones N, Evan GI. The cell cycle and how it is steered by Kaposi’s sarcoma-associated herpesvirus cyclin. J Gen Virol. 2004 Jun;85(Pt 6):1347-61. PMID: 15166416