Morphological and immunohistochemical diagnostic of extragastrointestinal stromal tumors – a 51 case series analysis

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the digestive tract, originating from structures differentiating towards Cajal cells. Due to their morphology and localization, the extragastrointestinal stromal tumors (EGISTs) can be a diagnostic challenge. We investigated a series of 51 EGISTs diagnosed in our institutions, aiming to explore the immunophenotypes and to analyze the process and the utility of the antibodies required for a positive diagnosis. Immunohistochemical examinations were done for pan-cytokeratin (pan-CK), Ki67, discovered on GIST1 (DOG1) protein and platelet-derived growth factor receptor alpha (PDGFRA), as necessary. The main tumor site was abdominal wall in 43 (84%) cases, most of the tumors showed spindle cell cellularity, followed by mixed and epithelioid type. Twenty-six cases revealed a full conventional immunohistochemical profile with DOG1 positivity. In 10 cases, c-KIT expression was absent but with the preservation of cluster of differentiation (CD)34 positivity, and eight cases were positive for PDGFRA. In our study, we found a subgroup of eight cases presenting in extra-abdominal settings (including one in lung and two in the head-and-neck area). We concluded EGISTs represent a histopathological and immunohistochemically challenging subgroup testing more often negative for c-KIT mutations and positive for PDGFRA compared to GIST. DOG1 remains the marker of choice regardless of tumor site, while CD34 and CD117 should be considered as adjuvants.

Lung cancer mimickers – a case series of seven patients and review of the literature

Background: Lung is the third most frequent identified site of malignancy and lung cancer is the most lethal type of cancer in the world. Several benign lung diseases or proliferations may mimic lung carcinoma in its clinical, pathological, and radiological presentation, which makes the differential diagnosis life changing. This case series was designed to describe the main diagnosis encountered in a multidisciplinary emergency hospital during the last years in Romania. Results: The most challenging cases encountered during the recent years were those of lung hamartoma associated with eosinophilic pneumonia because of the multicentricity of the disease and the suspicion for metastasis in the clinical setting, pulmonary aspergillosis that presented as a cystic lesion with a 9 mm mural nodule, actinomycosis discovered as firm nodule showing aspects of false pleural invasion, cryptococcosis – a hilar mass for which a pneumectomy was prepared, pulmonary parasitosis that presented as a nodule with irregular borders, causing pleural retraction, one case of inflammatory myofibroblastic tumor of the lung, one case of tumorlet type neuroendocrine lesion in a patient with history of melanoma and renal oncocytoma, admitted under the suspicion of lung metastasis. Conclusions: These are some of the main mimickers of primary or secondary lung cancers and one must be aware of these similitudes to avoid higher cost procedures, psychological stress for the patient and higher mortality.

Cutaneous melanoma arising on pre-existing nevi - case reports

Skin cancer is a common healthcare issue that affects millions of people worldwide. Only a small part of that population is suffering from melanoma and an even smaller proportion has melanoma developed on a pre-existing nevus. This paper illustrates five such cases, diagnosed over an 18-month period, with their histological particular aspects. Among the total number of patients diagnosed and treated in the Department of Plastic and Reconstructive Surgery, University Emergency Hospital, Bucharest, Romania, over approximately one year, of which half for melanoma in general or for benign nevi, only a small fraction had developed melanoma on a common or dysplastic nevus. These patients, as well as those with de novo developed melanoma, are a reason for concern since most of the lesions were diagnosed in a locally advanced stage of the disease. Though efforts are being made to screen and diagnose early, there are still a lot to be done in order to lower the mortality and morbidity rates for this pathology.

Cutaneous microcystic/reticular schwannoma: case report and literature review of an exceedingly rare entity with an unusual presentation

Conventional schwannoma represents a benign peripheral nerve sheath tumor derived from Schwann cells, which usually arises in the fourth or fifth decade of life, in the subcutaneous tissue of the distal extremities, or in the head and neck region of adult patients, with no gender predilection. In addition to the classic type, at least 11 different histopathological subtypes have been described and unawareness of these uncommon histopathological entities may lead to diagnostic pitfalls and risk of mistreatment. Recently described in the scientific literature, microcystic/reticular schwannoma is still relatively unknown to both surgeons and pathologists. The purpose of this paper is to highlight its existence by describing an additional case that occurred in the retroauricular area, and to further characterize its clinical, histopathological and immunohistochemical features. We reviewed the literature and compared the current case with others that have been documented thus far, discussing all possible differential diagnoses.

Keratoacanthoma centrifugum marginatum: an unusual clinical and histopathological diagnostic pitfall

Keratoacanthoma centrifugum marginatum (KCM) is a very rare variant of keratoacanthoma characterized by progressive peripheral growth accompanied by central healing. The tumor has the peculiar ability to involute spontaneously. A careful differential diagnostic with other skin carcinomas or hyperkeratotic lesions is required in order to ensure appropriate clinical management. We report a case of KCM in a 62-year-old man presenting with a solitary, large exophytic, sessile tumor located on the ventral side of the right lower leg, which developed over the course of one year from an initial erythematous papule. The patient presented history of local trauma. To our knowledge, this is the second report in the scientific literature supporting a possible traumatic etiology. Due to its rarity and lack of distinctive histopathological features, KCM poses a difficult diagnostic challenge. Therefore, the importance of an accurate histopathological examination and extensive use of ancillary studies for differential diagnosis is emphasized.

A challenging case of ocular melanoma

Ocular melanoma is a rare malignancy found in clinical practice. In this paper, we present a case of highly aggressive ocular melanoma, which was surgically removed at the Department of Ophthalmology and diagnosed at the Department of Pathology, Emergency University Hospital, Bucharest, Romania, using conventional histopathological techniques. Uveal melanoma, a subset of ocular melanoma, has a distinct behavior in comparison to cutaneous melanoma and has a widely divergent prognosis. Approximately half of patients with ocular melanoma will develop metastatic disease, predominantly with hepatic, pulmonary or cerebral location, over a 10 to 15 years period. No systemic therapy was associated with an evident clinical outcome for patients with advanced disease and overall survival rate remains poor.

Histopathological findings concerning ocular melanomas

Ocular melanoma is rare in clinical practice. In this study, we present three cases of ocular melanoma surgically removed in the Department of Ophthalmology of the Emergency University Hospital of Bucharest, Romania, and diagnosed in the Department of Pathology of the same hospital using conventional histopathological techniques and immunohistochemical tests.

Cutaneous verrucous carcinoma - report of three cases with review of literature

Verrucous carcinoma is a rare variant of squamous cell carcinoma. It is well differentiated and rarely metastases but can sometimes be very aggressive locally in depth. The paper presents three cases of cutaneous verrucous carcinoma with different localizations. The first patient shows a lesion in the sacrogluteal region, the second one presented a tumor localized on the auricle (external ear), and the third patient showed a tumor on the sole of the foot. All patients underwent tumor excision and the histopathological diagnosis was verrucous carcinoma. In the first two cases, the surgery was completely curative by excision of the tumors. In the last case, the patient had relapsed and due to the aggressive nature of the tumor, which infiltrated the deeper plans, the tumor had reached the bone. None of the patients showed any metastases.

Acantholytic squamous cell carcinoma: pathological study of nine cases with review of literature

Squamous cell carcinoma (SCC) is classified in many subtypes or forms; one of them is the acantholytic squamous cell carcinoma, also called pseudoglandular, adenoid, epithelioma dyskeratoticum segregans, or adenoacanthoma. Researching and analyzing nine cases of acantholytic squamous cell carcinoma, we intend to verify if the data provided by the cases studied can be validated by the scientific literature. All the cases presented lesions found on the head and neck skin, with two exceptions - one on the larynx and the other one on the tonsil, all of them ulcerated lesions. In two cases, the tumors developed on the skin, in preneoplasic lesions (actinic keratosis). The tumors had dimensions between 4/3/4 mm and 100/90/36 mm. During one year, two of the cases studied presented multiple recurrences. We also found two cases of metatypical carcinoma accompanied the acantholytic variant of squamous cell carcinoma. None of the analyzed cases presented distant metastasis. The histopathological criteria for selection were: keratinised squamous tumor cell type, adenoid structures with round spaces with a defined wall of at least one cell width, spaces with isolated or grouped dyskeratotic acantholytic cells.

Trichilemmal carcinoma - a rare cutaneous malignancy: report of two cases

The trichilemmal carcinoma is a rare low-grade malignant lesion originating from hair follicle cells that usually occurs on sun-exposed skin of older individuals. A differential diagnostic is required with other skin carcinomas. We report two cases of trichilemmal carcinoma admitted at the Emergency University Hospital of Bucharest, Romania, in 2012, one of these cases being localized in the periocular area and the other one resembling a cutaneous horn. These cases present several unusual aspects that are rarely described in the literature namely the site of the tumor which in the eyelid, development of a cutaneous horn, IHC tests which revealed EMA (epithelial membrane antigen) positivity in tumor cells. Considering that this type of tumor seldom develops metastases or local recurrences, and all the cases had free margins, there was no adjuvant therapy.