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Case Index

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

Clinical presentation:  Presents as a small skin covered nodule on the head and neck region, usually in the second decade of life. Tufts of vellus hair may protrude from a central umbilication.

 Microscopic features:   

The tumour consists of a dilated primary follicle lined by infundibular, stratified squamous epithelium, which may be connected to the epidermis.The lining epithelium has prominent granular layer. Secondary and tertiary follicles are present from the central follicle. The hair follicles are present at different levels of differentiation with  numerous vellus hairs within hair follicle lumen. Sebaceous glands may or may not be present.
Lymphocytic or granulomatous inflammation may be present in the connective tissue stroma.

Sebaceous trichofolliculoma is a variant of trichofolliculoma demonstrating numerous well differentiated sebaceous lobules emptying into the central primary follicle. This is very closely related to folliculosebaceous cystic hamartoma.

Trichofolliculoma has an excellent prognosis.

                 Image links 1  2(W Weems)

Abstracts:

Trichofolliculoma with incidental focal acantholytic dyskeratosis.South Med J. 2004 Aug;97(8):773-5

Trichofolliculoma of the vulva associated with vulvar intraepithelial neoplasia: report of three cases and review of the literature.Int J Gynecol Pathol. 2002;21 (3):224-230 

Immunohistochemical investigation of the different developmental stages of trichofolliculoma with special reference to the merkel cell. Am J Dermatopathol.1999;21: 8-15  

The trichofolliculoma undergoes changes corresponding to the regressing normal hair follicle in its cycle.J Cutan Pathol.1998; 25: 341-353  

Recurrent trichofolliculoma of the upper eyelid margin.Ophthal Plast Reconstr Surg. 1997;13(4):287-8

Folliculo-sebaceous cystic hamartoma is a trichofolliculoma at its very late stage. J Cutan Pathol 1998; 25: 354-364   

Sebaceous trichofolliculoma.J Cutan Pathol.1980; 7:394-403

 

PULMONARY PATHOLOGY Congenital Cystic Adenomatoid  Malformation ; Acute Respiratory Distress Syndrome  ;Sarcoidosis ;Bronchiolitis ; Emphysema ; Bronchial Asthma ;Chronic Bronchitis Pulmonary Alveolar Proteinosis ; Lipid Pneumonia ; Pulmonary Hypertension ;Pulmonary edema ;Pulmonary Infection ; Pneumococcal Pneumonia ; Haemophilus influenza Infection;Klebsiella Pneumoniae ; Mycoplasma Pneumonia ; Pneumocystis Pneumonia ; Legionellosis ; Localized Fibrous Tumour of the Pleura ; Biphasic Epithelial/Mesenchymal Lung Tumours ; Pulmonary Carcinosarcoma ;Pulmonary Blastoma ; Large Cell Neuroendocrine tumour;

Soft Tissue Pathology; Myxoid Tumours of Soft Tissue ;  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 ;

Hair Germ Differentiation:

Trichoepithelioma 

Desmoplastic Trichoepithelioma

Trichofolliculoma

Trichoblastoma

Cutaneous lymphadenoma

                               
Infundibular differentiation:

Trichoadenoma

Dilated Pore of Winer

Pilar Sheath Acanthoma

Tumour of Follicular Infundibulum

Outer root sheath differentiation:
                    
Trichilemmoma

Trichilemmal Carcinoma

Proliferating Trichilemmal Cyst (Pilar Tumour)

Matrical differentiation:
                  
Pilomatrixoma and Pilomatrix Carcinoma

Lichen planus-like lesions

Bullous Pemphigoid

Hailey-Hailey Disease 

Granuloma Annulare

Necrobiosis Lipoidica

Necrobiotic Xanthogranuloma   

Rheumatoid Nodule

Foreign body granuloma

Rosacea

Erythema Nodosum