Sturgis, Charles D.

Abstract Introduction/Objective Anaplastic thyroid carcinoma (ATC) is a fatal malignancy. We report an unusual case of a patient with ATC whose chief complaint and clinical history were listed as “jaundice and liver mass” without mention of disease in the neck. Methods/Case Report A 66-year-old female presented to the emergency department with worsening “yellow-green skin discoloration” for a few weeks. She also reported worsening dyspnea and recent dysphagia with solid foods, fatigue, abdominal pain and recent hemoptysis. Physical examination revealed conjunctival icterus, jaundice, a tender neck mass, right upper chest wall tenderness and palpable lymphadenopathy in the lower neck. Assessment notes indicated inability to carry out self-care and being bedridden, even though she reported having been active, swimming and cycling, up to one month before her presentation. Computed tomography studies confirmed findings compatible with widespread malignancy with mass lesions in her liver, lungs, adrenals, kidneys, neck, pancreas, gallbladder, and brain. Mild anemia, hemoglobin 10.5g/dL, mild leukocytosis, leukocytes 17,000/mm3, were confirmed. Bilirubin was 15µmol/L, and hepatic enzymes were elevated. An ultrasound-guided liver biopsy was performed and evaluated for cytologic features, histologic features and pattern of immunoreactivity. The combined cytomorphologic and histologic features were those of a pleomorphic sarcomatoid high-grade malignancy with variably spindled to epithelioid morphology and associated necrosis. Immunohistochemical studies performed on sections from the accompanying core biopsy confirmed the malignant cells to be positive with CK-AE1/AE3, CK 7, TTF-1, GATA3, PAX8, SATB2, and BRAF V600E. The malignant cells were nonreactive with CK 20, thyroglobulin, calcitonin, napsin, CDX2, PCEA, and ER. The combined clinical setting, imaging findings, cytomorphology, histomorphology and ancillary testing results together allowed for a specific diagnosis of metastatic anaplastic thyroid carcinoma. The patient was referred for palliative care services and died within a few days of diagnosis. Results (if a Case Study enter NA) NA Conclusion Metastatic disease from a sarcomatoid ATC, as diagnosed in this case, is an important differential diagnosis to keep in mind when an elderly patient presents with multisite metastases from an undefined primary source. Clinical, radiological and laboratory correlations are of paramount importance in correlating with cytomorphology/histomorphology and in helping to determine the best panel of IHC studies to consider.

AimsDue to its rarity and non‐specific clinical and pathological features, low‐grade adenosquamous carcinoma (LGASC) of the breast continues to pose diagnostic challenges. Unlike other triple‐negative breast carcinomas, LGASC tends to have an indolent clinical behaviour. It is essential to recognise this lesion for accurate diagnosis and appropriate management.Methods and resultsTwenty‐five cases of LGASC were identified in our archives and collaborating institutes. Cases of LGASC with dominant coexisting other type carcinomas were excluded. We studied the clinical presentation, morphological features, patterns of the commonly used immunohistochemical stains and follow‐up. In our cohort, LGASC was commonly located at the outer aspect of the breast and associated with intraductal papilloma. The morphology of LGASC is characterised by infiltrating small glands and nests with variable squamous differentiation. We also found cuffing desmoplastic (fibrolamellar) stromal change in 75% of patients and peripheral lymphocytic aggregates in 87.5% of patients. P63 and smooth muscle myosin (SMM) were the most common myoepithelial markers used to assist in diagnosis. P63 often stained peripheral tumour cells surrounding invasive glands (circumferential staining in 80% of the cases), mimicking myoepithelial cells. It also stained the small nests with squamous differentiation. However, SMM was negative in 63% of the cases. The vast majority of our cases were triple‐negative; only a few had focal and weak expressions of ER and PR. One patient who did not have excision developed lymph node metastasis. Most patients underwent excision or mastectomy with negative margins as surgical treatment; there were no recurrences or metastases in these patients with clinical follow‐ups up to 108 months.ConclusionsLGASC has some unique, although not entirely specific, morphological features and immunohistochemical staining patterns. Fibrolamellar stromal change, peripheral lymphocytic aggregates and variable staining of p63 and SMM are valuable features to facilitate the diagnosis.

Pseudoangiomatous stromal hyperplasia (PASH) of the breast is histologically characterized by anastomosing and slit-like spaces invested by collagenous stroma and lined by flattened, spindle cells. These clear spaces that may mimic microscopic vascular channels do not contain red blood cells. Immunohistochemistry (IHC) studies may also help to confirm a diagnosis of PASH, with the spindled cells marking positively with CD34 and PR while demonstrating no reactivity with more specific endothelial antigens such as CD31 and ERG. In the current case, a 39-year-old female was diagnosed with cellular PASH of the right breast with unique histological patterns showing “tiger-striped” and “zippered” histologies. To our knowledge, this is the first report of these unique variant PASH morphologies.