Soft tissue tumours of the penis. The 30-year Istituto Nazionale Tumori di Milano experience.

Objective: Small series and individual cases of penile soft tissue tumours are reported in the literature: these are rare tumours that represent less than 5% of all penile tumours. Methods: Penile soft tissue tumours were collected from the archive of the Department of Pathology at the Istituto Nazionale dei Tumori of Milan between January 1990 and October 2021. All available medical records were retrieved and reviewed to obtain clinical information. Results: Our series refers to the 30-year experience of highlighting the heterogeneity in the presentation and microscopic features of these rare sarcomas. 18 penile soft tissue tumours are described, 4 benign and 14 malignant. The mean age at diagnosis was 58.2 years (range 24-96 years) and 53.6 years among malignancies (range 24-89). The most frequent histotype was Kaposi's sarcoma (nr = 4) and very unusual histotypes were observed, namely low-grade fibromyxoid sarcoma, synovial sarcoma, proximal type epithelioid sarcoma and the first reported case of dedifferentiated liposarcoma of the penis. Conclusions: Among sarcomas of the genitourinary tract, tumours of the soft tissues of the penis are the rarest. Penile sarcomas can present at a young age. Kaposi's sarcoma in HIV-negative patients has a favorable outcome, while deep sarcomas have an aggressive behavior and poor prognosis.

Pleural Kaposi sarcoma: an unusual clinical case.

Kaposi sarcoma is a low-grade mesenchymal tumor associated with human herpesvirus-8. Here we describe the case of a 37-year old woman, who underwent to kidney and liver transplant for congenital hepatic fibrosis and bilateral polycystic kidney, with successive immunosuppressive therapy. After 5 years from first transplant, she developed cutaneous, mucosal, pleural and nodal localizations of Kaposi sarcoma, without lung lesions. Because of an initial clinical presentation with an important nodal and pleural involvement, a diagnosis of a lymphoproliferative disease was suspected. Pathological examination of the pleural sample allowed to exclude lymphoproliferative neoplasia and was consistent with Kaposi sarcoma. Subsequently involvement of other sites was diagnosed as expression of diffuse disease. The interest of this case lays in the unusual clinical presentation which can lead to diagnostic pitfalls when evaluating pleural biopsies.

Spread of hyperplastic pulmonary neuroendocrine cells into air spaces (S.H.I.P.M.E.N.T.S): A proof for artifact.

OBJECTIVES: Spread through air spaces (STAS) is a recently proposed invasion way of lung cancer, including neuroendocrine (NE) neoplasms. However, if this phenomenon is a real one or an artifact while manipulating lung specimens, it is still matter of debate. MATERIAL AND METHODS: Three consecutive patients with newly diagnosed diffuse idiopathic pulmonary NE cell hyperplasia (DIPNECH) were reviewed for STAS. RESULTS: In well-fixed lung specimens, DIPNECH was seen to coexist with atypical carcinoid, bifocal typical carcinoid and adenocarcinoma in the three patients, respectively. While STAS was not observed at the growing edges of tumors, a few freely-floating aggregates of hyperplastic NE cells within air spaces were noticed to emanate from foci of NE hyperplasia and tumorlets and in intimate association with normal bronchiolar cells and erythrocytes to denote artifactual derivation upon tissue manipulation. CONCLUSIONS: Traveling of hyperplastic NE cells through air spaces is likely to artifactually occur via knife, surgeon or other way, thus challenging invasion by STAS.