Pleomorphic ductal carcinoma of the breast with predominant micropapillary features

An 83-year-old woman with long-standing chronic ischemic cardiac and obstructive pulmonary disease, presented with a painless tumor in her right breast. Microscopically the tumor consisted of micropapillary formations and loosely cohesive nests and strands of large, highly pleomorphic cells. Micropapillary formations were surrounded by peritumoral retraction clefting, and the papillae lacked a true fibrovascular core. Multinucleated giant and bizarre tumor cells were also present and numerous. Within the tumor a high-grade intraductal component with the same cell morphology and necrosis and mucin production was found. Micropapillary pattern occupied approximately 60% of the tumor mass, loosely cohesive nests and strands approximately 20% and an intraductal component was noted in approximately 20% of the tumor mass. On immunohistochemistry the tumor cells were positive for pan-cytokeratin, epithelial membrane antigen (EMA), S100 protein and E-cadherin while estrogen and progesterone receptors, HER2-neu and Bcl2 were negative. EMA staining was diffuse and observed in the outer and inner margins of neoplastic nests. The diagnosis of pleomorphic breast carcinoma with predominant micropapillary features was established. In summary, micropapillary carcinoma can be distinguished from other types of breast carcinoma with micropapillary growth pattern on the basis of reverse cell polarity, which is easily confirmed on immunohistochemistry.     

Low-grade endometrioid carcinoma of the ovary associated with undifferentiated carcinoma: case report and review of the literature

The association of low-grade endometrioid carcinoma with undifferentiated carcinoma (UC) was first reported in endometrium carcinoma, termed with dedifferentiated carcinoma (DC). However, the coexistence of low-grade endometrioid carcinoma (LGEC) or serous carcinoma (LGSC) with UC has received minimal attention in ovary, and the behavior of this kind of neoplasm remains at further discussion. In this study, we reported a case of low-grade ovarian endometrioid carcinoma associated with UC and reviewed another four cases previously reported. We found a histological continuity between the LGEC and UC components in H&E section, which suggested a dedifferentiation from LGEC to UC components. In summary, this kind of pathological type has aggressive behavior and these patients have very poor prognosis regardless of the amount of undifferentiated carcinoma.     

Squamous cell carcinoma variants of the head and neck

Variants of squamous cell carcinoma (SCC) frequently arise within the mucosa of the upper aerodigestive tract, accounting for up to 15% of SCCs in these areas. The most common variants include verrucous, exophytic or papillary, spindle-cell (sarcomatoid), basaloid and adenosquamous carcinoma. Each of these variants has a unique histomorphologic appearance, which raises a number of different differential diagnostic considerations, with the attendant clinically relevant management decision.Verrucous squamous cell carcinoma has a broad border of pushing infiltration of a non-dysplastic squamous epithelium, essentially devoid of mitotic figures, displaying hyperkeratosis on elongated rete pegs. Papillary and exophytic SCC have a papillary or exophytic architecture, but have malignant cytologic features within the epithelium. Spindle-cell (sarcomatoid) carcinoma is an SCC blended with a spindle-cell morphology, frequently mimicking other mesenchymal tumours. Epithelial markers are often negative. Basaloid SCC is a high-grade SCC variant with small cells arranged in a palisaded architecture, with hyperchromatic nuclei and only focal areas of squamous differentiation. Adenosquamous carcinoma is a rare variant, which is a composite of adenocarcinoma and squamous cell carcinoma, often with areas of transition. The cytomorphologic features are described in detail in an attempt to allow the general surgical pathologist to separate these variants of SCC in order to achieve appropriate clinical management.     

Endometrial carcinomas with ambiguous features

Endometrial carcinomas are a heterogenous group of tumors that show variable histologies, molecular abnormalities and clinical outcomes. The idea of rigid distinctions between tumor types is appealing to pathologists, gynecologists, researchers and patients, but in a recent study where high grade endometrial carcinomas were reviewed by three experienced gynecologic pathologists, diagnostic agreement about tumor type was reached in only approximately one half of cases. In general, biologically and clinically validated diagnostic criteria are lacking for high grade endometrial carcinomas and for those that appear mixed epithelial. Until such criteria are developed, it remains important to define which morphologic patterns convey accurate clinical and biological information and which do not or might not. "Endometrial carcinomas with ambiguous features," the focus of this review, are tumors with comparatively uninformative morphologic features. Some publications indicate that gland forming and papillary endometrial carcinomas that appear morphologically low grade or ambiguous are really high grade. There are also indications that high grade endometrial carcinomas are biologically heterogeneous and that the morphologic clues we currently use to distinguish one subtype from another fail to correlate with biological data. Many tumors that appear morphologically mixed are, in fact, not biologically or clinically confused: most represent biologically "pure" tumors with variant morphology. Interesting associations between the presence of Lynch Syndrome (hereditary nonpolyposis colorectal carcinoma syndrome) and ambiguous morphology have been discussed in the literature. An apparent relationship between morphologic ambiguity and malignant mixed Müllerian tumor (MMMT) also exists. The identity of some morphologically ambiguous endometrial carcinoma can be elucidated with immunohistochemistry or other ancillary techniques at present, but the nature of many still remains undefined. This review presents the concept of morphologically ambiguous endometrial carcinomas, proposes morphological gold standard diagnostic criteria for tumors that are not ambiguous (an effort that helps define tumors that are ambiguous), provides a relevant literature review and offers practical guidance for sorting through diagnostically challenging cases.     

Small cell (oat cell) carcinoma of the breast

A case of small cell (oat cell) carcinoma, which represents both the most dlstlnctlve and the least common type of mast carcinoma wtth neuroendocrine dlfterentiation and usually shows the most aggressive behavior, is described. Radlcal mastectomy was performed on a Wyearold female for a 10 cm tumor located in the outer part of the right breast with cutaneous ulceration Microscoplcally, the tumor predominantly consisted of a diffuse proliteration of small, round to ovoid cells with hyperchromatlc nuclei and ill-defined, scant cytoplasm that was reminiscent of oat cell carclnoma of the lung. There were foci of invasive ductal carcinoma and ductal carcinoma in situ . Small cell carcinoma areas constituted approximately 90% of the neoplasm. The patlent had axlllary lymph node metastasis. The small tumor cells were argyrophlllc and positive for CAM5.2, carclnoembryonic antigen, neuron-specific enolase, Leu-7, chromogranln A and synaptophysin. Flow cytometric analysis showed an aneuplold DNA content. The patient was alive and well without disease 4 years after surgery. Small cell carcinomas of the breast may exhibkt a spectrum of malignancy that is comparable to similar tumors at better known primary sites.     

Molecular abnormalities in ovarian carcinoma: clinical,morphological and therapeutic correlates

The histopathological classification of ovarian surface epithelial carcinomas (referred to hereafter as ‘ovarian carcinoma’) has shifted over the past 10 years to reflect more clearly our understanding of molecular events during carcinogenesis. Ovarian carcinoma is no longer viewed as a single entity but as multiple disease processes, with each having different molecular pathways altered during oncogenesis, resulting in differences in clinical and pathological features, such as biomarker expression, pattern of spread and response to chemotherapy. There are five subtypes of ovarian carcinoma that are sufficiently distinct and well‐characterized that they should be considered to be different diseases, i.e. high‐grade serous, clear cell, endometrioid, mucinous and low‐grade serous, from most to least common, respectively. This review summarizes the molecular abnormalities of these five ovarian carcinoma subtypes, relating them to clinical and pathological features.     

Columnar cell variant of papillary thyroid carcinoma: A diagnostic dilemma in fine‐needle aspiration cytology

Columnar cell variant of papillary thyroid carcinoma (PTC) is an uncommon variant with an aggressive course as compared to classic papillary carcinoma. Cytologic diagnosis of these tumors is difficult due to absence of characteristic nuclear features of classic pattern of papillary carcinoma. We present a case of columnar cell variant in a young female misdiagnosed on aspiration cytology. A 21‐year‐old female presented with solitary nodule in the left aspect of thyroid. A diagnosis of medullary thyroid carcinoma was rendered. The resected thyoroidectomy specimen revealed a columnar cell variant of PTC which was further supported by immunohistochemical staining. Diagn. Cytopathol. 2016;44:816–819. © 2016 Wiley Periodicals, Inc.     

The encapsulated follicular carcinoma of the thyroid

Summary In a retrospective study of 86 follicular carcinomas of the thyroid gland, 35 lesions were classified as encapsulated carcinomas (40.7%). In two of these, lymph node metastases were detected initially. Another patient presented with distant metastases. The biological behaviour of these 35 tumours was studied over a long-term follow-up period (0.4–19.1 years, mean 10.3 years) which featured three cases of death from thyroid carcinoma 0.4–5.0 years after thyroidectomy. Another patient suffered from local recurrence of a follicular carcinoma 13.9 years later. The morphological and clinical findings of those five patients who initially presented with metastases and/or whose follow-up registered the local recurrence of thyroid cancer or death as a result of it, were compared with the remaining 30 cases which were of a benign clinical course. Statistical analysis showed that the prognosis of encapsulated follicular carcinoma is more serious when tumours occur in patients older than 65 years of age and when the tumour diameter is 5.0 cm or more. There was a tendency towards poorer prognosis in those tumours exclusively composed of oxyphilic epithelium.Sponsored by: Hamburger Stiftung zur Förderung der Krebsbekämpfung     

Histopathologic approaches to the infiltrative renal mass

Most renal masses are round or oval, well-circumscribed, and demonstrate a well-defined interface from the normal renal parenchyma. However, a small subset of renal tumors exhibits an infiltrative pattern, with a poorly-defined interface with the renal parenchyma and entrapment of normal structures. These infiltrative renal malignancies generally show more aggressive clinical course and are associated with a poorer prognosis compared to the more typical renal neoplasms. Main differential diagnoses for a renal mass with infiltrative histology would include urothelial carcinoma, fumarate hydratase (FH)-deficient renal cell carcinoma (RCC), medullary RCC, metastatic cancer from another organ, and rare patterns of clear cell or papillary RCC. Non-epithelial processes may include lymphoma and various infectious, inflammatory, immune-mediated, and vascular mimics. Collecting duct carcinoma is extremely rare in modern practice and is essentially a diagnosis of exclusion once the previous considerations are thoroughly argued against. The aim of this review is to familiarize pathologists with the spectrum of entities that can present as infiltrative masses in the kidney, and to highlight the most relevant immunohistochemical or other tools to facilitate accurate diagnoses and appropriate patient management.     

Papillary carcinoma of the thyroid with anaplastic transformation: diagnostic pitfalls in fine-needle aspiration biopsy

A case of coexistent papillary and anaplastic carcinoma of the thyroid is presented. The diagnosis of papillary carcinoma was made by fine-needle aspiration biopsy (FNAB); however, it did not correspond to the aggressive clinical behavior of the tumor. Subsequent biopsies revealed anaplastic carcinoma in the thyroid and pretracheal tissue. This case most likely represents anaplastic transformation in a pre-existing papillary carcinoma. The limitations of diagnosing this entity by FNAB as well as some possible solutions are discussed.     

Primary oat-cell carcinoma of the larynx

Summary A primary oat-cell carcinoma of the larynx in a 63-year-old man is reported. The oat-cell pattern appeared intermingled at one edge with a squamous carcinoma. The origin of this mixed tumour is considered together with the literature of extrapulmonary carcinomas having an oat-cell pattern.     

High-grade mucoepidermoid carcinoma of the breast

A case of high-grade mucoepidermoid carcinoma of the breast with a dominantly epidermoid component is presented. The tumour was biochemically oestrogen and progesterone receptor negative. Though the primary tumour was small (1 cm) and without axillary lymph node metastases at mastectomy, the clinical course was rapid. Despite radio-, chemo- and hormonal therapy the patient died 25 months after mastectomy with widespread systemic disease. The metastatic pattern was that of typical breast carcinoma despite the unusual histological appearance of both primary and metastatic tumour tissue.     

Columnar cell carcinoma of the thyroid

A case of columnar cell carcinoma of the thyroid occurring in a 50-yearoid female is described. Histologically, the 2 cm tumor showed a prominent papillary architecture with thin fibrous cores covered by columnar cells and marked nuclear stratiflcation. It also showed microfollicular, glandular, and solid pattems. The nuclear features were different to those of conventional papillary carcinomas and similar to those of follicular tumors. The tumor was principally encapsulated with vascular and minimal capsular invaslon. The tumor cells were positive for thymglobulin. The tumor was DNA diploid with a low S phase fraction as determined by flow cytometry. The patient had no lymph node or distant metastasis. The patient was well and without disease 9 months after surgery. The possibility that the neoplasm is one of poorly differentiated thyroid carcinomas rises.     

Oat cell carcinoma of the larynx. A study of six new cases

Clinicopathological details of six oat cell carcinomas of the larynx are presented. Five patients were male and heavy smokers. Only two patients had lymph node metastases at diagnosis. Only one tumour was unequivocally Grimelius stain positive. Immunostaining for neurone-specific enolase was negative in all cases. Neurosecretory granules were found in two tumours studied electron microscopically. Three tumours had areas of squamous carcinoma. Laryngectomy was the treatment of choice. Two patients are alive without evidence of disease 21 and 25 months after diagnosis.     

Composite encapsulated papillary carcinoma and solid papillary carcinoma

Encapsulated papillary carcinoma (EPC) and solid papillary carcinoma (SPC) are distinctive variants of intraductal papillary carcinomas, each accounting for <1% of breast carcinomas. Here we report a composite carcinoma consisting of EPC and SPC. A 73‐year‐old woman was found to have a high density mass in the left breast on mammogram. A biopsy showed intermediate to high grade ductal carcinoma in situ (DCIS). Gross examination of the lumpectomy specimen revealed a solid, multinodular mass. Microscopic examination demonstrated two morphologically distinct intraductal carcinomas intermingled with each other. One had delicate papillae in multi‐cystic spaces surrounded by thick fibrous capsule, consistent with EPC. The other had solid tumor nests with delicate fibrovascular cores. The cells were monotonous with round nuclei and salt and pepper‐like chromatin, characteristic of SPC. The lack of myoepithelial cells within the papillae and at the periphery of the lesion was confirmed by immunostaining for p63 and CK5/6. Neuroendocrine differentiation of SPC was demonstrated by neuron specific enolase staining. To our knowledge, this is the first reported case of composite EPC and SPC. It raises an interesting question as to a possible common pathway of carcinogenesis of these two rare variants.