In cis TP53 and RAD51C pathogenic variants may predispose to sebaceous gland carcinomas.

Pathogenic variants in TP53 have been classically thought to cause Li-Fraumeni syndrome (LFS), a cancer predisposition with high risks for various childhood- and adult-onset malignancies. However, increased genetic testing has lately revealed, that pathogenic variant carriers exhibit a broader range of phenotypes and that penetrance may be dependent both on variant type and modifiers. Using next generation sequencing and short tandem repeat analysis, we identified germline pathogenic variants in TP53 and RAD51C located in cis on chromosome 17 in a 43-year-old male, who has developed a rare sebaceous gland carcinoma (SGC) but so far no tumors of the LFS spectrum. This course mirrors a Trp53-Rad51c-double-mutant cis mouse-model, which similarly develops SGC, while the characteristic Trp53-associated tumor spectrum occurs with significantly lower frequency. Therefore, we propose that co-occurent pathogenic variants in RAD51C and TP53 may predispose to SGC, reminiscent of Muir-Torre syndrome. Further, this report supports the diversity of clinical presentations associated with germline TP53 alterations, and thus, the proposed expansion of LFS to heritable TP53-related cancer syndrome.

[Alopecia areata universalis under treatment with sitagliptin : Possible immunological effect of dipeptidyl peptidase-4 inhibitors?] / Alopecia areata universalis nach Sitagliptin-Einnahme : Mögliche immunologische Wirkung von Dipeptidylpeptidase-4-Inhibitoren?

A 64-year old man developed alopecia universalis after one month of treatment with metformin and sitagliptin, a dipeptidyl peptidase­4 (DPP-4) inhibitor. Diabetes treatment was changed to another genericum of sitagliptin and dapagliflozin. Following our recommendation, sitagliptin was interrupted and monotherapy with dapagliflozin was continued. After 6 weeks, sitagliptin was reassumed due to unsatisfactory diabetes control. Alopecia did not improve. We suspect a connection between DPP­4 inhibition and development of alopecia due to its immunological potential. We assume that the treatment interruption might have been too short to induce regrowth of hair. DPP­4 may result in both inhibition and activation of the immune system.

Erythematous scaling lesions of the face, dorsal fingers, elbows, and knees together with symmetrical muscle weakness in a child.

Juvenile dermatomyositis shows characteristic skin lesions. However, this does not rule out co-occurring other autoimmune diseases, which may be more prominent regarding skin manifestations. Co-occurring other skin autoimmune diseases should not be regarded as a preclusion for dermatomyositis. Here, we present an impressing case of juvenile dermatomyositis with co-occurring psoriasis.