Lichen planus-like lesions

Bullous Pemphigoid

Hailey-Hailey Disease 

Granuloma Annulare

Necrobiosis Lipoidica

Necrobiotic Xanthogranuloma   

Rheumatoid Nodule

Foreign body granuloma

Rosacea

Erythema Nodosum

Role of immunohistochemistry in Dermatopathology 

Cutaneous Pseudolymphoma

Drug related cutaneous lesions

Cutaneous lesion in graft-
versus host disease

Classification of Soft Tissue Tumour

Gross examination of soft tissue specimen          

A practical approach to histopathological reporting of soft tissue tumours

Grading of soft tissue tumours

Lipomatous tumours

Neural tumours

Myogenic tumours

Fibroblastic/Myofibroblastic tumours

Myofibroblastic tumours

Fibrohistiocytic tumours

ChondroOsseous tumours

Soft TissueTumours of Uncertain Differentiation               

Notochordal Tumour - Chordoma

Extra-adrenal Paraganglioma

Gastrointestinal Stromal Tumour

Diagnosis of Path Quiz Case 25:

Apocrine hidrocystoma/Cystadenoma:
Adenomatous cystic proliferation of apocrine glands. Some regard them as retension cysts, others regard some of these lesions with epithelial proliferation as benign tumours - Apocrine Cystadenoma.

Clinical presentation:  These may present as  uni or multilocular cystic structures containing clear or brownish fluid.  It is suggested that the pigmentation observed clinically is due to the Tyndall phenomenon.

ImageLink (JHU): 

Site:  Located on the head and neck of older patients. Other sites include trunk and genital region.

Microscopic features:  Cysts are lined by two layers of cells. The inner layer consists of tall columnar cells with eosinophilic cytoplasm and showing decapitation secretion. The outer layer consists of myoepithelial cells. The apocrine cells probably contain  lipofuscin  granules. These granules are PAS positive and diastase resistant.

Rarely, the lining epithelium shows papillary proliferation - Papillary apocrine gland cyst.    (D/D: Hidradenoma papilliferum or  syringocystadenoma papilliferum.)

Immunohistochemistry:   Gross cystic disease fluid protein has been identified.

Apocrine hidrocystomas grow gradually and usually do not recur after excision.

             Image links: (Dr.Weems)

Eccrine mucinous metaplasia associated with an apocrine cystadenoma.J Cutan Pathol. 2005;32(4):307-9.

Multilocular eyelid hidrocystoma: an anatomical and clinical observation.J Fr Ophtalmol. 2003  ;26(1):106-9.

Multiple apocrine hidrocystomas: treatment with carbon dioxide laser vaporization.J Dermatolog Treat. 2001 ;12(2) :97-100.

Immunohistochemical analysis of cytokeratin expression in apocrine cystadenoma or hidrocystoma.J Cutan Pathol. 1999 ;26(6):295-300.

Apocrine cystadenoma, apocrine hidrocystoma, and eccrine hidrocystoma: three distinct tumors defined by expression of keratins and human milk fat globulin 1.J Cutan Pathol. 1997 ;24(4) :249-55.

Multiple hidrocystomas.Dermatology. 1996;193(2):152-3.

The hybrid epidermoid and apocrine cyst. A combination of apocrine hidrocystoma and epidermal inclusion cyst.Am J Dermatopathol. 1996;18(4):364-6.

Multiple hidrocystoma of the face: three cases.Clin Exp Dermatol. 1995;20(4):323-7.

Pigmented apocrine hidrocystoma--a report of two cases and review of the literature. off.Clin Exp Dermatol. 1991;16 (1):18-21.

Apocrine hidrocystoma--a report of five cases and review of the Japanese literature.J Dermatol. 1989;16(4):315-20.

S-100 protein-positive cells in hidrocystomas.J Cutan Pathol. 1986 ;13(2):102-10.

The nature of pigment in pigmented apocrine hidrocystoma. J Cutan Pathol. 1985;12(2):106-9.

These are small ductal cysts lined by simple epithelium, usually found in adults.

Site: Usually located on the head, neck, trunk and chest.

Microscopic features:   Cysts are lined by single layer of cuboidal cells. The myoepithelial cell layer is absent.
No decapitation secretion or PAS- positive cytoplasmic granules are present.
Cytokeratin 7, 8 and 19 are expressed in some cases .

Multiple eccrine hidrocystomas.Australas J Dermatol. 2004 ; 45(3):178-80.

Multiple eccrine hidrocystomas of the face.Int J Dermatol. 2001;40(2):125-9.

Multiple eccrine hidrocystomas associated with Graves' disease.J Dermatol. 1996;23(9):652-4. 

Squamous cell carcinoma arising in an eccrine hidrocystoma. Pathology. 1993;25(2):184-6.

Eccrine hidrocystoma. Hautarzt. 1989;40(10):647-9.

Eccrine hidrocystoma of the external ear canal: a case report.J Otolaryngol. 1987;16(1):43-5.

Cysts:

Hydrocystoma -Eccrine/Apocrine

Hamartomas:

Eccrine/Apocrine naevus

Eccrine Angiomatous Hamartoma

Porokeratotic eccrine ostial naevus

Benign Neoplasms:

Syringocystadenoma Papilliferum

Hidradenoma Papilliferum

Nipple Adenoma

Syringoma

Spiradenoma

Cylindroma

Chondroid Syringoma (benign mixed tumour)

Poroma

Hidradenoma

Apocrine adenoma

Papillary eccrine adenoma

Syringofibroadenoma

Malignant sweat gland tumour