Primary breast liposarcoma is a rare subtype of breast sarcoma. In men, it is extremely rare and has generally been reported in the literature as case reports. An 82-year-old man presented with a painless, slowly growing mass in his left breast that had been present for 5-6 months. On examination, the mass measured approximately 20 cm and extended into the axilla. Mammography, breast MRI, and PET-CT demonstrated a fat-containing mass extending from the breast into the axilla. The mass had an indistinct border with the pectoral muscle, several solid areas, and mild FDG uptake (SUVmax, 2.5). Similar hypermetabolic areas were observed in the pectoral muscle and axilla. Core needle biopsy suggested dedifferentiated liposarcoma. The patient underwent simple mastectomy with resection of the pectoral muscle and axillary lymph node sampling. Final pathology of the surgical specimen showed a predominantly well-differentiated liposarcoma with two small foci of dedifferentiation and a low mitotic index, with no necrosis or pleomorphism identified, and confirmed histological infiltration of the pectoralis major muscle fibers. No metastasis was observed in the axillary lymph node sampling. The patient recovered well, and no adjuvant therapy was recommended. There was no recurrence or metastasis at 10 months of follow-up. This case demonstrates that pectoral muscle invasion, although rare, can occur in breast liposarcoma. It also demonstrates that the extent of dedifferentiation identified on biopsy may differ from that identified on final pathology. Finally, this case highlights that a definitive diagnosis requires comprehensive histopathological examination.

C. auris is an emerging multidrug-resistant (MDR) fungal pathogen that poses an urgent threat to global public health. It is characterized by rapid nosocomial transmission, persistent environmental survival, and extensive cross-resistance to conventional antifungal therapies. This comprehensive narrative review bridges the fundamental molecular mechanisms of intrinsic and acquired antifungal resistance with host adaptation strategies and emerging clinical interventions. C. auris resistance is driven by a highly sophisticated network of genetic mutations and metabolic reprogramming distributed across six geographically distinct clades (I-VI), including the newly identified Clade VI from the Indomalayan zone. Azole resistance primarily relies on clade-specific point mutations in the target gene ERG11, synergistically amplified by TAC1b-driven transcriptional upregulation of the CDR1 efflux pump. Echinocandin resistance is predominantly mediated by conformational reshaping across three distinct hotspot regions of the FKS1 gene, bolstered by Hsp90-mediated stress compensatory networks. For polyenes, while clinical resistance is frequently overestimated by commercial assays, true tolerance mechanisms involved the depletion of target ergosterol and profound non-sterol-dependent sphingolipid remodeling. Beyond genomic modifications, C. auris exhibits significant phenotypic plasticity, forming robust, polysaccharide-rich biofilms on indwelling medical devices that confer profound physical drug tolerance. Clinically, the fungus demonstrates a strong cutaneous tropism-predominantly colonizing the axilla and groin-which acts as the primary reservoir for hospital outbreaks. Furthermore, experimental models reveal that C. auris actively exploits host immune deficiencies, specifically subverting the IL-17A/neutrophil/S100A8 axis, to evade immune clearance and establish persistent colonization. To overcome these formidable MDR bottlenecks, therapeutic paradigms are rapidly evolving. The integration of next-generation antifungals such as the long-acting echinocandin rezafungin, fosmanogepix, and ibrexafungerp, synergistic combination therapies, quorum-sensing inhibitors such as farnesol, and experimental nanocarrier delivery systems could represent promising frontiers to effectively dismantle the complex defense networks of C. auris.

Primary cutaneous adenoid cystic carcinoma (PCACC) is a rare cutaneous adnexal malignancy. Although its clinical course is generally considered more indolent than that of salivary gland-derived counterparts, PCACC exhibits a significant propensity for local recurrence and a notable potential for distant metastasis. Here, we report a rare case of PCACC arising in the right axilla. Based on a comprehensive literature review and statistical analysis of previously reported cases, our findings suggest that a tumor diameter of ≥ 2.0 cm may be associated with an increased risk of metastasis. Therefore, for patients with tumors exceeding 2.0 cm, we suggest that careful determination of surgical margins and comprehensive staging evaluations-including whole-body PET-CT, sentinel lymph node biopsy, and long-term postoperative follow-up-may be considered.

Primary malignancy in accessory breast tissue is an infrequent diagnosis representing less than 1% of all breast cancers and most commonly presents with a palpable mass in the axilla. Furthermore, a concurrent second primary breast cancer found in accessory breast tissue is an extremely rare phenomenon, although reports of these are on the rise. Extra-mammary sites where second primary breast malignancies have been reported include the inframammary fold, the abdomen and even the vulva. When an ectopic immunobreast malignancy is suspected, triple assessment is the standard approach to investigation. However, there are no specific treatment guidelines, and it therefore follows the same guidelines as for pectoral breast cancer. Here, we present a report of a 71-year-old female being treated for a left breast cancer, diagnosed with a concurrent second primary breast carcinoma in the right upper quadrant of the abdominal wall, which was surgically managed with wide local excision and sentinel lymph node biopsy. This case highlights the importance of maintaining a high index of suspicion during assessment of these patients in order to establish the correct diagnosis at an early stage.