Checkpoint inhibitors and radiotherapy in refractory malignant melanocytic schwannoma with Carney complex: first evidence of efficacy

Genomic alteration profile and PD-L1 expression among different breast cancer subtypes in Chinese population and their correlations

BACKGROUD

There were limitations existing in programmed cell-death ligand 1 (PD-L1) as predictive biomarkers for breast cancer (BC), hence exploring the correlation between PD-L1 levels and other biomarkers in BC may become a very useful therapeutic clinical tool.

METHODS

A total of 301 Chinese patients with different BC subtypes including 47 HR+/HER2+, 185 HR+/HER2-, 38 HR-/HER2+, and 31 triple-negative breast cancer (TNBC) were enrolled in our study. Next-generation sequencing based Yuansu450 gene panel was used for genomic alteration identification and PD-L1 expression was tested using immunohistochemistry.

RESULTS

The most prevalent BC-related mutations were TP53 mutations, followed by mutations in PIK3CA, ERBB2, CDK12, and GATA3 in our Chinese cohort. We found that mutations DDR2 and MYCL were only mutated in HR-/HER2+ subtype, whereas H3-3A and NRAS mutations were only occurred in HR-/HER2- subtype. The percentage of patients with PD-L1-positive expression was higher in patients with HR-/HER2- mainly due to the percentage of PD-L1-high level. Mutational frequencies of TP53, MYC, FAT4, PBRM1, PREX2 were observed to have significant differences among patients with different BC subtypes based on PD-L1 levels. Moreover, a positive correlation was observed between TMB and PD-L1 level in HR+/HER2- subtype, and showed that the proportion of patients with high PD-L1 expression was higher than that of patients with low PD-L1 expression in the HR+/HER2- and HR+/HER2+ cohorts with high Ki67 expression.

CONCLUSIONS

The genomic alterations based on PD-L1 and other biomarkers of different cohorts may provide more possibilities for the treatment of BC with different subtypes.

Carney complex with multiple breast tumours including breast cancer: a case report

Carney complex (CNC) is a rare multiple tumour syndrome characterized by cutaneous pigmented lesions, myxoma and endocrine tumours, among others, and is inherited as an autosomal dominant trait. Protein kinase cAMP-dependent type I regulatory subunit alpha (PRKAR1A) is known to be the responsible gene. Breast myxomatosis and ductal adenoma, which are regarded as benign, are well-known mammary lesions of CNC and are included in the main diagnostic criteria. In this case, a 59-year-old woman with repeated cardiac myxoma was diagnosed with CNC with PRKAR1A mutation. She also had three multiple breast tumours bilaterally: breast cancer, adenomyoepithelioma and intraductal papilloma. In mammary lesions of CNC, attention should be paid to benign lesions, such as breast myxomatosis or ductal adenomas, and the development of breast cancer or breast tumours with malignant potential. Mammary lesions should be aggressively scrutinized and considered for resection, as required.

Post-operative Stereotactic Radiosurgery of Malignant Melanotic Schwannoma

Melanotic schwannoma is an extremely rare schwannoma variant with malignant potential, demonstrating high local and distant recurrence. Given the paucity of data, recommended treatment with localized disease is radical resection, with the unclear benefit of adjuvant therapy. We present a case of an 18-year-old female with no past medical history or genetic syndromes who underwent margin-positive resection of an S1 nerve root melanotic schwannoma followed by adjuvant stereotactic radiosurgery (SRS). SRS was delivered without acute or late toxicity by 2.5 years post-treatment. She remains without evidence of recurrent disease, although longer follow-up is needed given the risk of late recurrence. Our case adds to the limited literature documenting the efficacy of adjuvant radiotherapy in melanotic schwannoma and is the first to describe the successful use of SRS for this rare disease.