We report a rare case of giant uterine leiomyosarcoma in a postmenopausal woman, whose diagnosis was initially suspected at the evaluation of the abdominal efusion, and confirmed after the pathological examination of the uterus in association with the ancillary tests. The evaluation of the abdominal fluid showed single or clusters of malignant, round or spindle-shaped cells. On microscopic examination of the surgical specimen, a dense cell proliferation of spindle cells, with moderate to severe nuclear pleomorphism and significant mitotic activity was observed. Immunohistochemical evaluation demonstrated the loss of myocytic differentiation by focal, weakly positive expression of smooth muscle actin and desmin. The data presented in this case emphasize the relevance of the cytological examination, although the latter has only indicative value, especially since it is an aggressive tumor, frequently associated with mutant expression of p53. In our case, the first indication of the presence of uterine sarcoma was given by the presence of atypical cells in the peritoneal fluid.

Mammary Paget’s disease (MPD) is a rare histological condition, accounting for 1-4% of female breast cancers, which may appear either independently (1.4-13% of the cases), or in association with an in situ or invasive ductal carcinoma (approximately 90% of the cases). The purpose of this article is to highlight the histopathological challenges related to the microscopical polymorphism of this disease and the utmost importance of immunohistochemistry in the thorough process of Paget’s disease differential diagnosis. Moreover, the primary objective of this review of literature was to corroborate the existing data concerning the potential peculiar immunohistochemical profile that mammary Paget’s disease might express. We report the case of a 44-year-old female patient, histopathologically diagnosed with HER2-negative MPD accompanying an invasive mammary carcinoma. The histopathological and immunohistochemical approach is derived from the exigency of excluding the possibility of synchronous tumors—a mammary invasive carcinoma, accompanied by another component with MPD phenotypic mimicry. The unexpected negative HER2 reaction is conducted to a primary focus on excluding a malignant melanoma in situ. The absence of MelanA and S100 immunoexpression and lack of pigmentation and clinical aspects infirmed it. Bowen’s disease was invalidated by its rare presentation in the breast cutaneous tissue and the absence of individual risk factors suggestive of an existing immunosuppressive status. In the case of similar morphoimmunohistochemical aspects, significant expression of Ki-67 signals MPD, an immunoreactivity that helped distinguish the cellular population from Toker cells. The great similarity of MPD with other benign and malignant cutaneous tumors might determine delay or misdiagnosis. Thus, the utmost importance of immunohistochemistry is reflected in its prognostic significance and geared towards extending the therapeutic arsenal.

Spontaneous regression of cutaneous melanoma represents a more frequent circumstance in tumors with intense MelanA immunoprofile. Melanoma-derived breast metastases are uncommon and have been predominantly reported in premenopause, as an indicator for widespread disease. We report the case of a 60-year-old female patient, who presented to the surgical department after auto-palpation of a left mammary mass. Digital mammography indicated malignant characteristics, also objectified in the ipsilateral axillary lymph nodes. The microscopical examination and immunohistochemical profile revealed left nodal and upper-outer mammary quadrant metastases of a BRAF-positive achromic melanoma. The clinical and dermoscopic evaluation confirmed the complete regression of the malignant melanocytic lesion, localised at the level of the right inframammary fold. The upper-outer breast quadrant designates the main site of primary tumors (66%), as well as metastases of other malignancies (50%), due to its well-represented vascularisation and glandular tissue. Dermoscopic characteristics of regressed melanoma comprise scar-like depigmentation and polymorphous vessels (irregular linear and globular). The particularities of this case include the age > 40 years old, survival under therapy with Vemurafenib superior to that cited in the literature (24 months to this date), the involvement of the contralateral lymph nodes in relation to the skin lesion and the inverse diagnostic approach – from pathologist to dermatologist. Completely regressed achromic melanoma, identified through diagnostic techniques performed on clinically apparent loco-regional and distant metastases, represents a rare dermato-oncological entity, with controversial implications regarding the prognosis and survival, that requires future histopathological and dermoscopic homogenization.