Spiradenoma is a benign dermal tumour occuring in adults.

This lesion often coexists with cylindromas.

Clinical presentation:

Usually presents as a painful or tender solitary nodule (less than 1cm in diameter).

May occasionally present as multiple lesions .

Giant variants, linear or zosteriform distribution have also been reported. 

Site:  Head & neck,  sometimes on the scalp and on the trunk. Rarely on the extremities.

Microscopic features: 

Tumour consists of sharply demarcated lobules located in the dermis without connection to the epidermis ;  Eosinophilic PAS positive basement membrane-like material may be present around the lobules ; 

Two cell types are present ; Small cells with dark nuclei are present at the periphery and the large paler cells are at the centre ;

Cells are arranged around small lumina ;  Lumina contains small amounts of granular eosinophilic material that is PAS- positive and diastase resistant ;

Numerous small lymphocytes are present throughout the tumour lobules.

Tumour may show prominent degenerative changes, fibrosis and cyst formation ; Ancient changes (dilated vessels rimmed by sclerosis) ; 

Larger tumours are partially or totally necrotic ; 

Immunohistochemistry:  Strands of cells are cytokeratin positive and lumina are CEA positive.

Malignant transformation of spiradenoma (Spiradenocarcinoma) may occur in rare cases.

Brooke-Spiegler syndrome is a rare, autosomally dominant disease characterized by the development of multiple cylindromas, trichoepitheliomas, and occasional spiradenomas.

Abstracts:

Eccrine spiradenoma: co-expression of cytokeratin and smooth muscle actin suggesting differentiation toward myoepithelial cells.J Eur Acad Dermatol Venereol. 2007 Jan;21(1):121-3.

Multiple linear spiradenoma with a linear distribution.
Actas Dermosifiliogr. 2006 Jan-Feb;97(1):31-4.

Giant vascular eccrine spiradenoma: report of a case with immunohistochemical study.J Korean Med Sci. 2006 Feb;21(1):172-6.

Congenital blaschkoid eccrine spiradenoma on the face. Eur J Dermatol. 2005 ;15(2):73-4.

Brooke-Spiegler syndrome: report of a case with combined lesions containing cylindromatous, spiradenomatous, trichoblastomatous, and sebaceous differentiation.Am J Dermatopathol. 2005;27(1):27-33.

Two cases of multiple eccrine spiradenoma with linear or localized formation.J Dermatol. 2004;31(7):564-8.

Brooke-Spiegler syndrome associated with cylindroma, trichoepithelioma, spiradenoma, and syringoma.J Dermatol. 2004;31(1):32-8

Familial eccrine spiradenoma: a case report and review of the literature.Dermatol Surg. 2003;29(4):411-4.

Multiple eccrine spiradenomas on the hand, forearm and head.Dermatology. 2002;205(4):401-4.

Blaschkoid eccrine spiradenomas.Cutis. 2002;70(1):73-5.

Multiple linear eccrine spiradenomas with eyelid involvement.J Eur Acad Dermatol Venereol. 2001;15(2):163-6.

Cell proliferation in skin tumours with ductal differentiation: patterns and diagnostic application.J. Cutan Pathol  2000; (27): 292-7

Multiple eccrine spiradenomas in zosteriform distribution in a child.Pediatr Dermatol. 2000;17(5):384-6.

Spiradenocylindromas of the skin: tumors with morphological features of spiradenoma and cylindroma in the same lesion: report of 12 cases.Pathol Int. 1999;49(5):419-25.

Spiradenoma and dermal cylindroma comparative immunohistochemical analysis and histogenetic considerations. Am J Dermatopathol 1997 ; 19: 154-161.

Non-epithelial cellular components in eccrine spiradenoma: a histological and immunohistochemical study of 20 cases. Histopathology 1991 ; 18: 155-160 

Eccrine spiradenoma: clinical and pathologic study of 49 tumors.J Cutan Pathol. 1983;10(5):312-20.

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