Cutaneous and superficial soft tissue lesions associated with Albright hereditary osteodystrophy: clinicopathological and molecular genetic study of 4 cases, including a novel mutation of the GNAS gene

Atypical Non-neoplastic Changes in Anogenital Mammary-like Glands Accompanying Invasive Squamous Cell Carcinoma

Long regarded as ectopic or supernumerary breast tissue, anogenital mammary-like glands (AGMLG) are now considered a normal constituent of the anogenital area. AGMLG are presumed to be the origin for various benign and malignant lesions. Changes in AGMLG compatible with usual ductal hyperplasia and atypical ductal hyperplasia considered as precursor lesions and its presence in specimens can be explained by their role in the pathogenesis of primary extramammary Paget disease. In this report, we presented four cases of invasive squamous cell carcinoma accompanied by non-neoplastic atypical changes in ductal portions of AGMLG compatible with atypical ductal hyperplasia in breast adjacent to the carcinoma. This is a reactive phenomenon similar to that seen in apocrine/eccrine glands adjacent to squamous cell carcinoma. In a limited biopsy specimen, these areas should not be mistaken for adenocarcinoma.

Calcinosis Cutis Circumscripta Of Knee-A Rare Presentation

Introduction:

Calcinosis circumscripta is a form of ectopic mineralization characterized by single or multiple cutaneous nodules containing calcium salts. Calcinosis cutis circumscripta is a very rare form of idiopathic calcinosis cutis arising in the second half oflife. It typically involves the extremities and is associated with prior trauma and scleroderma. We dealt with a very rare form of calcinosis cutis circumscripta in a healthy patient, for whom surgical excision revealed to be an effective and successful treatment.

Case presentation:

33-year-old male presented to OPD with swelling over the right knee joint. Clinically the swelling was adhered to skin, bony hard, tender, and movements of right knee were painful. The patient was investigated and once fit was taken for surgery. The patient was treated surgically by excising the swelling.

Conclusion:

Surgical excision is the mainstay of the treatment. Indications for surgical removal include pain, recurrent infection, ulceration, and functional impairment. Following excision, however, recurrence is common.

A mouse model for osseous heteroplasia

GNAS/Gnas encodes G_sα that is mainly biallelically expressed but shows imprinted expression in some tissues. In Albright Hereditary Osteodystrophy (AHO) heterozygous loss of function mutations of GNAS can result in ectopic ossification that tends to be superficial and attributable to haploinsufficiency of biallelically expressed G_sα. Oed-Sml is a point missense mutation in exon 6 of the orthologous mouse locus Gnas. We report here both the late onset ossification and occurrence of benign cutaneous fibroepithelial polyps in Oed-Sml. These phenotypes are seen on both maternal and paternal inheritance of the mutant allele and are therefore due to an effect on biallelically expressed G_sα. The ossification is confined to subcutaneous tissues and so resembles the ossification observed with AHO. Our mouse model is the first with both subcutaneous ossification and fibroepithelial polyps related to G_sα deficiency. It is also the first mouse model described with a clinically relevant phenotype associated with a point mutation in G_sα and may be useful in investigations of the mechanisms of heterotopic bone formation. Together with earlier results, our findings indicate that G_sα signalling pathways play a vital role in repressing ectopic bone formation.

Fibroblastic and myofibroblastic tumors in children and adolescents

Fibroblastic and myofibroblastic tumors in children and adolescents are a relatively common group of soft tissue proliferations that range from reactive to hamartomatous to neoplastic, with a full spectrum of benign, intermediate, and malignant neoplasms. These lesions are diagnostically challenging because of morphologic and immunohistochemical overlap, despite significant clinical, genetic, and prognostic differences. The fibromatoses are a major subgroup, and all types of fibromatoses can occur in the 1st 2 decades of life. Intermediate and malignant fibroblastic-myofibroblastic tumors are an important group that includes variants of fibrosarcoma and other tumors with recurrent cytogenetic or molecular genetic abnormalities and low metastatic potential. Pathologic examination is enhanced by adjunct techniques, such as immunohistochemistry, cytogenetics, and molecular genetics, although morphology provides the ultimate criteria for a specific diagnosis. This article reviews the clinicopathologic features of fibroblastic and myofibroblastic tumors with an emphasis on the unique aspects of these neoplasms in children and adolescents, the use of diagnostic adjuncts, and differential diagnoses.