ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 within an otherwise borderline phyllodes tumour. The patient under- went further axillary sampling, and remains well. Conclusion: Although the occurrence of invasive carcinomas within phyllodes tumours is rare, their existence must be consid- ered by the pathologist. Due to its rarity, there is limited clinical outcome data specifically regarding disease progression and patient prognosis in invasive lobular carcinoma within phyllodes tumours. It is therefore important to highlight these rare cases and build on the volume of data in the literature. E-PS-02-023 Subtleties of early breast implant-associated anaplastic large cell lymphoma – a potential for missed-diagnosis A. Behzadnia, H. Ali, N. Duhli, L. Karsai, A. Elhag, N. Briggs, M. Rourke, A. Rahman, B. Wooler, S. Bakhiet* *Hull University Hospitals NHS Trust, United Kingdom Background & objectives: Breast implant-associated anaplastic large cell lymphoma (BI-ALCL) is a rare and significant complication of breast augmentation surgeries. Early diagnosis depends on the cytology of the peri-implant effusion, as histologically it can resemble post- implant changes, posing a diagnostic challenge for pathologists. Methods: We present a case of a 57-year-old lady with a 12-year history of bilateral breast augmentation, presenting with a sud- den unilateral breast enlargement. On examination, asymmetri- cal enlargement of the right and a palpable nodularity of the left breasts were noted. Ultrasound revealed 310ml of right-sided fluid collection and a peri-implant well-circumscribed mass. Fine-needle aspiration and core needle biopsy were performed. Results: Fluid examination showed only a few CD68-negative, CD30-positive atypical lymphoid cells. Core biopsy of the left- sided nodularity showed benign reactive synovial metaplasia. Further radiological examination with MRI and CT-PET also demonstrated peri-implant effusion with very faint metabolic activ- ity. Patient underwent en-bloc removal of bilateral implants and peri-implant capsulectomy. Entire capsules were sampled as no abnormality was seen macroscopically or on initial microscopy. On further sampling, scattered hallmark cells were identified with a CD30+, IRF4+ and ALK- immunophenotype, seen mostly as singletons and a few small aggregates, that were confined to the luminal aspect of the right capsule, confirming the diagnosis of BI-ALCL. Molecular analyses revealed no DUPSP22 or TP63 rearrangement. Conclusion: Early-stage BI-ALCL has an indolent course, hence, early diagnosis is of paramount importance(1). Early findings may be inconspicuous, with scarce hallmark cells, and capsule changes that may resemble post-implant changes only, a real potential for misdiagnosis. Extensive sampling and a low-threshold for immunohistochemistry can aid the diagnosis. Absence of DUPSP22-IRF4/TP63 rearrangements in BI-ALCL distinguishes it from ALK-negative ALCL(2). When suspected, the first fluid aspirate has the best diagnostic value as the dilutional effect of subsequent effusions can delay the diagnosis(3). E-PS-02-024 A rare, unusual case of eosinophilic mastitis: case report T. Pasupati Meenakshi*, B. Karikalan *Gribbles Pathology M Sdn Bhd, Malaysia Background & objectives: Eosinophilic mastitis is a rare, benign breast entity and very few cases have been documented worldwide. We document a recent and rare case of eosinophilic mastitis, with a clinical differential diagnosis of malignancy or chronic granulomatous mastitis (CGM). Methods: A 50-year-old lady presented with a palpable right breast lesion at 12 o’clock, with architectural distortion, tenderness and lymphadenopathy. Grossly, multiple thin cores of greyish yellow tissue, ranging from 8mm to 14mm in length were received. Entire tissue was submitted in one block. Routine H&E was performed, and the histological features were reported digitally using Aperio Image Scope. Results: Multiple linear core biopsies of right breast lesion showed scattered normal appearing breast glands, a few cystically dilated, surrounded by striking distribution of abundant eosinophils, along with very occasional polymorphs and lymphocytes. Peri lobular concentration and aggregation of eosinophils and stromal infiltra- tion by eosinophils was seen throughout in all the core biopsies studied. Occasional ‘eosinophilic islands’ were present. There was also formation of eosinophilic emboli within a few of the dilated glands. No atypia or necrosis or features of lobular mastitis were seen. Conclusion: Isolated eosinophilic mastitis is extremely rare in occurrence and can be clinically mistaken for malignancy or chronic granulomatous mastitis (CGM). It can be associated with systemic involvement or occur without peripheral eosinophilia. The management of such cases is extremely different when compared to conventional ductal carcinoma or lobular mastitis. This benign entity reemphasizes the need for histopathological diagnosis of breast lesions prior to treatment. E-PS-02-025 Acquired lymphangiectasia following surgery and radiotherapy of breast cancer: report of two cases S. Graja*, M. Mellouli, S. Makni, M. Manai, N. Gouiaa, C. Kam- moun, T. Boudawara, I. Saguem *Department of Pathology, Habib Bourguiba University Hospital, Sfax, Tunisia Background & objectives: Acquired lymphangiectasia (AL) is a dila- tation of lymphatic vessels that can result as a complication of surgical intervention and radiation therapy for malignancy. We describe two new cases of AL and discuss their clinical and pathological features. Methods: Two patients aged of 40 and 56 years old were presented to the department of dermatology with vesicles and bullae in the chest evolving for two and one year. The patients had undergone radical mastectomy with axillary lymphadenectomy for breast car- cinoma 4 and 7 years ago respectively. They also had received a complementary radiotherapy and hormone therapy after surgery. Results: On examination, multiple grouped vesicles and bullae were spread over the left anterior and lateral wall of the chest for the first patient and in the right lateral wall of the chest for the second patient without evi- dence of lymphedema in the two cases. Few of the vesicles were purple in colour, pedunculated and hypertrophic. A biopsy was taken from lesions. Histopathological examination revealed numerous dilated lymphatics in the superficial and papillary dermis lined by flattened endothelial cells, with mild hyperkeratosis consistent with diagnosis of lymphangiectasia. The lesions were managed with sclerotherapy. No recurrences were notified. Conclusion: Clinically, AL manifests as translucent vesicles in a chronic lymphedematous area arising after many years following surgery with or without radiotherapy. The combination of surgery and irradiation increase their appearance comparing to surgery or irradiation alone and reduce the time of occurrence of AL. Treat- ment modalities include electrodessication, surgical excision and sclerotherapy. These two new cases has demonstrated the impor- tance of keeping lymphangiectasia in mind as a rare and late com- plication of radiotherapy and surgical procedures. S197