Kaposi sarcoma in unusual locations

Clinical challenge: cutaneous Kaposi's sarcoma of the lower extremity

Kaposi's sarcoma (KS) typically presents as multiple bilateral cutaneous patches or plaques of the lower extremities. This malignancy, however, can evolve with atypical presentation masquerading as a chronic wound. Lesions can mimic venous stasis ulcers, arterial insufficiency, vascular ulcers or chronic-infected wounds. With acquired immune deficiency syndrome (AIDS)-associated KS, lesions are even more widespread, and can affect the respiratory tract, lymph nodes, gastrointestinal tract, spleen, liver and, rarely, bone. As the initial diagnosis of KS is generally determined clinically, a high index of suspicion is necessary for all patients with a known or suspected history of HIV/AIDS. Tissue biopsy with histological analysis is essential for all wound types in this patient subset, regardless of wound presentation. The purpose of this report is to review the pathogenesis as well as the typical and atypical presentations of KS with an example of a diagnostic dilemma.

Conjunctival metastasis from Kaposi's sarcoma: a case report

We present one case of Kaposi's sarcoma with conjunctive metastasis. The case describes a 71-years-old white male, who was admitted at hospital by malaise, slight pain on the left eyelid, nodular lesion of the left leg, and enlarge lymph nodes in inguinal regions. The conjunctive neoplasms are rare, and we most frequently can see the pigment ones followed by squamous epithelials and lymphomas. The primary Kaposi's sarcoma (KS) from conjunctiva is a rare tumor and it has increased by AIDS emergence and immunosuppression. The appearance of conjunctival metastasis from KS is a stand out event.

Fine needle aspiration of salivary gland masses in HIV-infected patients

Salivary gland disease is an important manifestation of HIV-infection. The aim of this study was to evaluate the cytologic findings of salivary gland fine needle aspiration (FNA) in South African human immunodeficiency virus (HIV)-infected patients. A retrospective review was performed on confirmed HIV-positive patients who underwent FNA of various body sites, including salivary glands, over a 5-year period. There were 495 (14.1%) salivary gland FNAs out of a total of 3,501 HIV-positive patients. This included 260 (52.5%) parotid, 226 (45.7%) submandibular, 2 (0.4%) sublingual, and 7 (1.4%) specimens labeled as a salivary gland aspirate, exact site not provided. Patients were of average age 34 years (range 9 months to 63 years) with a female: male ratio of 1:0.6. There were 37 (7.5%) inadequate FNAs and 22 (4.4%) that contained normal gland constituents only. Most diagnoses were benign and comprised 168 (33.9%) reactive lymphadenopathy, 115 (23.2%) benign lymphoepithelial cysts, 62 (12.5%) mycobacterial infections, and 52 (10.5%) abscesses, of which 10 had associated mycobacterial infections. Neoplasms accounted for 31 (6.7%) diagnoses including 11 pleomorphic adenomas, 13 lymphoma, 3 Kaposi sarcoma, 1 squamous cell carcinoma, 1 metastatic carcinoma, and 1 rhabdomyosarcoma. There were four epidermoid inclusion cysts, three non-specific sialadenitis, one mucocele, and one spindle cell lesion not able to be further characterized. FNA is a useful procedure to evaluate salivary gland lesions in an HIV-infected population, allowing prompt management to be undertaken and obviating the need for surgery in many instances, an important consideration in an underfunded public health care system.

Diagnosis of Metastatic Neoplasms: A Clinicopathologic and Morphologic Approach

Context.—The diagnosis of the site of origin of metastatic neoplasms often poses a challenge to practicing pathologists. A variety of immunohistochemical and molecular tests have been proposed for the identification of tumor site of origin, but these methods are no substitute for careful attention to the pathologic features of tumors and their correlation with imaging findings and other clinical data. The current trend in anatomic pathology is to overly rely on immunohistochemical and molecular tests to identify the site of origin of metastatic neoplasms, but this “shotgun approach” is often costly and can result in contradictory and even erroneous conclusions about the site of origin of a metastatic neoplasm.

Objective.—To describe the use of a systematic approach to the evaluation of metastatic neoplasms.

Data Sources.—Literature review and personal experience.

Conclusions.—A systematic approach can frequently help to narrow down differential diagnoses for a patient to a few likely tumor sites of origin that can be confirmed or excluded with the use of selected immunohistochemistry and/or molecular tests. This approach involves the qualitative evaluation of the “pretest and posttest probabilities” of various diagnoses before the immunohistochemical and molecular tests are ordered. Pretest probabilities are qualitatively estimated for each individual by taking into consideration the patient's age, sex, clinical history, imaging findings, and location of the metastases. This estimate is further narrowed by qualitatively evaluating, through careful observation of a variety of gross pathology and histopathologic features, the posttest probabilities of the most likely tumor sites of origin. Multiple examples of the use of this systematic approach for the evaluation of metastatic lesions are discussed.

Classic Kaposi sarcoma with sarcoid-like granulomas: a case report and literature review

The occurrence of granulomatous reactions within lymph nodes that drain carcinomas is well known but uncommon. Even more rarely, granulomas may occur within the stroma of tumors. These lesions, called sarcoid-like reactions, commonly accompany carcinomas but are very rare in sarcomas. This study presents a case of classic Kaposi sarcoma that contained sarcoid-like granulomas, with a literature review. A soft tissue lesion of the foot was excised from a 74-year-old male. Histopathological examination showed that the tumor tissue consisted of spindle cells, areas of atypical vascular proliferation, and extravasated erythrocytes surrounded by non-caseating granulomas. The patient had no clinical or laboratory findings of sarcoidosis. The case was interpreted as "Kaposi sarcoma containing sarcoid-like granulomas". The association of soft tissue sarcomas with a granulomatous reaction is very rare. A granulomatous reaction is reported to be a good prognostic indicator in several carcinoma types, although its importance in sarcomas is unclear.

Pulmonary involvement in Kaposi sarcoma: correlation between imaging and pathology

Kaposi sarcoma is a low-grade mesenchymal tumor involving blood and lymphatic vessels. There are four variants of this disease, each presenting a different clinical manifestation: classic or sporadic, African or endemic, organ transplant-related or iatrogenic, and AIDS-related or epidemic. Kaposi sarcoma is the most common tumor among patients with HIV infection, occurring predominantly in homosexual or bisexual men. The pulmonary involvement in Kaposi sarcoma occurs commonly in critically immunosupressed patients who commonly have had preceding mucocutaneous or digestive involvement.

The etiology of Kaposi sarcoma is not precisely established; genetic, hormonal, and immune factors, as well as infectious agents, have all been implicated. There is evidence from epidemiologic, serologic, and molecular studies that Kaposi sarcoma is associated with human herpes virus type 8 infection. The disease starts as a reactive polyclonal angioproliferative response towards this virus, in which polyclonal cells change to form oligoclonal cell populations that expand and undergo malignant transformation.

The diagnosis of pulmonary involvement in Kaposi sarcoma usually can be made by a combination of clinical, radiographic, and laboratory findings, together with the results of bronchoscopy and transbronchial biopsy. Chest high-resolution computed tomography scans commonly reveal peribronchovascular and interlobular septal thickening, bilateral and symmetric ill-defined nodules in a peribronchovascular distribution, fissural nodularity, mediastinal adenopathies, and pleural effusions. Correlation between the high-resolution computed tomography findings and the pathology revealed by histopathological analysis demonstrate that the areas of central peribronchovascular infiltration represent tumor growth involving the bronchovascular bundles, with nodules corresponding to proliferations of neoplastic cells into the pulmonary parenchyma. The interlobular septal thickening may represent edema or tumor infiltration, and areas of ground-glass attenuation correspond to edema and the filling of air spaces with blood. These findings are a result of the propensity of Kaposi sarcoma to grow in the peribronchial and perivascular axial interstitial spaces, often as continuous sheets of tumor tissue.

In conclusion, radiological findings can play a major role in the diagnosis of pulmonary Kaposi sarcoma since characteristic patterns may be observed. The presence of these patterns in patients with AIDS is highly suggestive of Kaposi sarcoma.

Primary Kaposi sarcoma of the subcutaneous tissue

Background

Involvement of the subcutis by Kaposi sarcoma (KS) occurs primarily when cutaneous KS lesions evolve into deep penetrating nodular tumors. Primary KS of the subcutaneous tissue is an exceptional manifestation of this low-grade vascular neoplasm.

Case presentation

We present a unique case of acquired immune deficiency syndrome (AIDS)-associated KS manifesting primarily in the subcutaneous tissue of the anterior thigh in a 43-year-old male, which occurred without overlying visible skin changes or concomitant KS disease elsewhere. Radiological imaging and tissue biopsy confirmed the diagnosis of KS.

Conclusion

This is the first documented case of primary subcutaneous KS occurring in the setting of AIDS. The differential diagnosis of an isolated subcutaneous lesion in an human immunodeficiency virus (HIV)-infected individual is broad, and requires both imaging and a histopathological diagnosis to guide appropriate therapy.