Two cases of Kaposi's sarcoma mimicking Stewart-Treves syndrome found to be human herpesvirus-8 positive

Unusual Localization of AIDS-Related Kaposi's Sarcoma in a Heterosexual Male during the COVID-19 Pandemic: A Case Report

Kaposi's sarcoma is an AIDS-defining illness and remains the most frequent tumor arising in HIV-infected patients with multifactorial etiology. We present a case of a 30-year-old Caucasian male with an 18-year history of HIV infection. The patient was presented with a one-week history of fever, non-productive cough, and skin lesions. There was an associated weakness and weight loss in a duration of 6 months. Clinical examination showed fever, generalized lymphadenopathy, lower limb edema, ascites, and violaceous cutaneous eruption comprising patches, plaques, and nodules. He also had a red nodule on the left conjunctiva, as well as on his oral mucosa. His CD4+ count was below 10/mm3 and ARN-HIV viral load was above 100,000 c/mL, in relation to the antiretroviral failure after five drug regimens. The role of co-infections in oncogenesis and the course of Kaposi's sarcoma were considered in recent studies. Delayed diagnosis of Kaposi's sarcoma in the present case resulted in a negative impact for this patient during the COVID-19 pandemic.

Kaposi sarcoma following postmastectomy lymphedema

Classical Kaposi sarcoma (KS) usually appears on lower extremities accompanied or preceded by local lymphedema. However, the development in areas of chronic lymphedema of the arms following mastectomy, mimicking a Stewart-Treves syndrome, has rarely been described. We report an 81-year-old woman who developed multiple, erythematous to purple tumors, located on areas of post mastectomy lymphedema. Histopathological examination evidenced several dermal nodules formed by spindle-shaped cells that delimitated slit-like vascular spaces with some red cell extravasation. Immunohistochemically, the human herpesvirus type 8 (HHV-8) latent nuclear antigen-1 was detected in the nuclei of most tumoral cells confirming the diagnosis of KS. Lymphedema could promote the development of certain tumors by altering immunocompetence. Although angiosarcoma (AS) is the most frequent neoplasia arising in the setting of chronic lymphedema, other tumors such as benign lymphangiomatous papules (BLAP) or KS can also develop in lymphedematous limbs. It is important to establish the difference between AS and KS because their prognosis and treatment are very different. Identification by immunohistochemistry of HHV-8 is useful for the distinction between KS and AS or BLAP.

Kaposi sarcoma: a continuing conundrum

Kaposi sarcoma (KS) remains a challenge. Its classic or Mediterranean form tends to be benign. In transplant recipients it may be less so. As part of the AIDS pandemic, of which it was an original defining component, it may be life-threatening. It is due to human herpesvirus-8, which is necessary but not sufficient to produce the disease. KS has a low prevalence in the general population of the United States and United Kingdom, with an intermediate rate in Italy and Greece, and a high one in parts of Africa. In Italy, hot spots include its southern regions, the Po River Valley, and Sardinia, possibly related to a high density of blood-sucking insects. An important challenge is to treat KS patients without immunocompromising them. The potential of effective anti-herpes virus therapy and the use of sirolimus in transplantation recipients have added new opportunities for KS prevention.

LEARNING OBJECTIVES

At the conclusion of this learning activity, participants should be able to provide the most recent information about Kaposi sarcoma in the context in which it occurs. Its classic or Mediterranean form, its pattern in transplant recipients and others iatrogenically immunosuppressed, and its occurrence as a potentially life-threatening part of the AIDS pandemic will be stressed. Its etiology and transmission will be discussed in detail to facilitate understanding of Kaposi sarcoma and of human herpesvirus-8 infection in the general population of the United States and United Kingdom, in Italy and Greece, and in certain parts of Africa. Its therapy, including the concept of doing it without immunocompromising the patient, will be stressed. New opportunities for Kaposi sarcoma prevention will also be discussed.

Angiosarcoma arising in a lymphedematous abdominal pannus with histologic features reminiscent of Kaposi's sarcoma: report of a case and review of the literature

BACKGROUND

Despite common endothelial origins, angiosarcoma and Kaposi's sarcoma are clinically and histologically distinct vascular proliferations. The development of angiosarcoma in a chronically edematous abdominal pannus is extremely uncommon. Similarly, tumors with the combined histologic features of angiosarcoma and Kaposi's sarcoma have rarely been described.

METHODS

We reviewed the literature on angiosarcoma arising in a lymphedematous abdominal pannus and evaluated an 81-year-old morbidly obese woman who had profound, long-standing edema of the lower abdominal wall in which an aggressive vascular tumor developed.

RESULTS

Three clinically similar cases were identified in the literature. All patients were women who generally experienced rapid disease progression. In addition, in our patient, sequential cutaneous sampling from different lesional sites demonstrated disparate histologic changes, ranging from those of classic Kaposi's sarcoma to high-grade angiosarcoma, to areas with combined features of the two tumors. A polymerase chain reaction performed on lesional tissue was negative for human herpesvirus-8 DNA.

CONCLUSION

It is important to note that angiosarcoma may develop in the abdomen in association with chronic lymphedema, as demonstrated by the cases noted in this report. In addition, our case highlights the difficulty in differentiating histologically angiosarcoma from Kaposi's sarcoma in some situations, and demonstrates the value of close clinicopathologic correlation and sequential tissue sampling in evaluating problematic cases.

Vascular tumors of the skin: A selective review

Cutaneous vascular proliferations are a vast and complex spectrum. Many appear as hamartomas in infancy; others are acquired neoplasms. Some vascular proliferations are hyperplastic in nature, although they mimic hemangiomas, i.e., neoplasms. The vast majority of the vascular lesions are hemangiomas. Between the hemangiomas and frankly angiosarcomas, there is a group of neoplasms that are angiosarcomas, albeit ones of low grade histologically and, probably, biologically. The term "hemangioendothelioma" has been created to encompass these neoplasms. Vascular proliferations are, fundamentally, composed of endothelial cells. Some hemangiomas, however, contain also abundant pericytic, smooth muscle, or interstitial components, or a combination of them. These heterogeneous cellular components are present usually in hemangiomas. Some of the newly described vascular proliferations, however, are difficult to differentiate from some of the angiosarcomas. Others are markers, occasionally, of serious conditions such as Fabry's Disease (angiokeratoma) and POEM's syndrome (glomeruloid hemangioma). Kaposi's sarcoma continues to be an enigma. The demonstration of Herpes virus 8 in this condition raises doubt about its neoplastic nature. The demonstration of endothelial differentiation of its nodular lesions is tenuous and its true nature remains unresolved. While physicians have known about post-mastectomy angiosarcomas from the origin of the radical mastectomy, a new group of unusual vascular proliferations of the mammary skin are being defined. These lesions arise in the setting of breast-conserving surgical treatment with adjuvant radiation therapy. The incubation period is usually 3 to 5 years, in contrast with the 10, or more, in classical cases of post-mastectomy angiosarcoma. These lesions usually are subtle, both clinically and histologically, in contrast with the "classical," dramatic presentation of mammary angiosarcoma. The spectrum of findings ranges from "simple" lymphangiectasia-like vascular proliferations to unequivocal angiosarcomas. The pathogenesis of these lesions remains a mystery. There are very few clues that allow one to separate hemangiomas from angiosarcomas. The presence of heterologous cellular elements and, particularly, well-developed smooth muscle components tends to favor a hemangioma. Similarly, the presence of thrombosis usually supports hemangioma. Nevertheless, there are no unequivocal or reliable individual diagnostic criteria. A thorough knowledge of the different conditions and their differential diagnoses eventually leads to the proper diagnosis in most cases.

Kaposi's sarcoma: An update

While there have been many important advances in the study of Kaposi's sarcoma (KS), it remains both a challenge and an enigma in many ways. Kaposi's original description of "multiple idiopathic hemorrhagic sarcoma[s]" in patients who died within 2-3 years resembles KS in AIDS more than classic KS in elderly men of Italian, Jewish, or Mediterranean lineage, in whom the disease is usually benign. KS had been evident in about one-third of those with early AIDS, often as its presenting sign, a pattern markedly reduced in recent times since the introduction of highly active anti-retroviral therapy (HAART). The most important advance has been the convincing etiologic linkage of KS with human herpesvirus 8 (HHV-8), which is necessary but not sufficient. It has a low prevalence in the general population of the USA and UK, with an intermediate rate in Italy and Greece, and a high one in Uganda. KS risk may be significantly lower in AIDS patients with a history of anti-herpes therapy. Many aspects of HHV-8, including its transmission pattern and different genospecies, are being scrutinized. The diagnosis of KS may be difficult. One should be aware of KS clinical variants, including telangiectatic, eccymotic, and keloidal KS. One must consider a number of other disorders, including bacillary angiomatosis. HHV-8 DNA sequences in dermatofibromas and other tumors should probably not be viewed as representing a marker for KS. Therapeutic options vary for KS. Intralesional and low-dose outpatient intravenous vinblastine may be valuable, as immunosuppression with KS is not a good idea if it can be avoided. Anti-herpes virus therapy may have potential for wide use, especially in preventing the development of KS in at risk populations, such as HHV-8 seropositive individuals undergoing transplantation surgery.