Cytologic features of microcystic adnexal carcinoma

Nodular Hidradenocarcinoma, Trichelemmal Carcinoma and Squamous Cell Carcinoma with Clear Cell Changes: Pitfalls of Biopsy Diagnosis of Skin and Adnexal Tumours

Skin and Adnexal tumours are a group of benign and malignant tumours whose basic diagnosis relies on histopathology. A single tumour may show more than 1 appendageal differentiation. Morphologic distinction between benign and its malignant counterpart is of utmost importance as it affects the treatment and prognosis of patient. We have described 3 cases who presented in our university hospital, in which final resection pathological diagnosis differed from initial core biopsy interpretation. The authors have made an attempt to provide a brief overview of diagnostic overlap existing between nodular hidradenocarcinoma and tumours of clear cell histology. Salient morphologic features differentiating cylindroma or trichilemmal carcinoma from squamous cell carcinoma have also been discussed. Final diagnosis is paramount for adjuvant management and prognostication of the patient in a clinical setting.

Histopathologic pitfalls of Mohs micrographic surgery and a review of tumor histology

Mohs micrographic surgery is a specialized subset of staged surgical excisions with each subsequent stage being driven largely by the histologic findings of the previous stage. Therefore, it is imperative that histologic analysis is performed in an accurate manner. Frozen section and tissue flattening is a crucial step in Mohs surgery. Frozen sections introduce certain artifacts and these artifacts must be interpreted in the correct context. Basal and squamous cell carcinomas are the most common tumors encountered in Mohs micrographic surgery, and their histopathology is also associated with certain "pitfalls". Basal cell carcinoma should be distinguished from hair follicles, folliculocentric basaloid proliferations, poromas, nevus sebaceous, desmoplastic trichoepitheliomas, and spiradenomas, to name but a few histologic entities. Similarly, squamous cell carcinoma should be distinguished from hypertrophic actinic keratoses, pseudoepitheliomatous hyperplasia, sebaceous carcinoma, and microcystic adnexal carcinoma. In addition, there are numerous subtypes of basal cell and squamous carcinomas that the Mohs surgeon should be aware of due to differences in the biologic behavior of these tumors. This review presents a number of the common histologic pitfalls of Mohs micrographic surgery and a review of tumor histology.

Challenges in the diagnosis of cutaneous adnexal tumours

The diagnosis of cutaneous adnexal neoplasms, a heterogeneous group of entities, is often perceived by practising pathologists as challenging. A systematic approach to diagnosis is necessary for classification of these lesions, which establishes the tumour differentiation (follicular, sebaceous, sweat gland or apocrine) and evaluates histological features differentiating between benign and malignant entities. Consideration of clinical history is a necessary adjunct in evaluation of the adnexal neoplasm, as characteristic anatomical sites are described for many adnexal lesions. In some instances, immunohistochemical studies may also be employed to aid the diagnosis. The differential diagnosis between primary cutaneous adnexal neoplasms and cutaneous metastases from visceral tumours may also be difficult. Clinical, radiological, histological and immunohistochemical characteristics will be further discussed, considering that the correct diagnosis has a significant impact on the patient's management and prognosis.

Treatment of nasal microcystic adnexal carcinoma with an expanded rotational forehead skin flap: A case report and review of the literature

Microcystic adnexal carcinoma (MAC) is a rare and locally aggressive adenocarcinoma with low-grade malignancy. The present study describes the first reported case and treatment of a Chinese male with a MAC located on the nasal dorsum and nosewing. A 44-year-old man presented with a nasal deformity caused by local repeated infections following an accidental injury to the nose 20 years previously. The nose had been injured by a brick, and treatment at a local hospital 12 years previously had resulted in a nasal scar and a gradually enlarging mass. A physical examination revealed a hypertrophic deformity of the nose and an indurated scar plaque, measuring 2.0×2.0 cm, on the nasal dorsum and nosewing. Microscopic examination revealed a tumor consisting of solid cell nests and a cystic structure with a capsular space. In addition, ductal cells of an adnexal cell origin were visible in the outer epithelium. The medial portion exhibited a microductal structure and invasion of deeper tissues without evident atypia. The tumor cells presented normal nuclear to cytoplasmic ratios and minimal mitotic activity. Pathological examination verified that the tumor was a MAC of low-grade malignancy. A complete surgical resection was performed via Mohs micrographic surgery (MMS), and reconstruction was achieved using an expanded rotational forehead skin flap. No tumor recurrence was detected after a three-year follow-up period. Therefore, for effective treatment of similar MAC cases, complete surgical resection using MMS is recommended, and successful reconstruction may be achieved using an expanded skin flap.

Thank you reviewers – CytoJournal 2011

CytoJournal, with its continued contribution of scientific cytopathology literature to the public domain under open access (OA) charter, thanks its dedicated peer reviewers for devoting significant efforts, time, and resources during 2011. The abstracts of poster-platform submissions to the 59^th Annual Scientific Meeting (November 2011) of the American Society of Cytopathology (ASC) in Baltimore, MD, USA, were peer reviewed by the ASC Scientific Program Committee.