Carney complex Q87.1

Carney complex is a rare autosomal dominant syndrome with multiple endocrine neoplasms and lentiginosis caused by defects in the PRKAR1A gene in most patients. The PRKAR1A gene copies for the type 1α regulatory subunit of protein kinase A. Inactivating mutations of PRKAR1A result in aberrant cyclic AMP protein kinase A signaling (Kamilaris CDC et al. 2019) .

The PRKAR1A gene is responsible for 2/3 of the cases (Carney syndrome type I). This syndrome is caused by an autosomal dominant mutation of the PRKAR1A gene (also called CNC1 gene, Carney complex type 1 gene) located at gene locus: 17q23-q24. Because most of the identified PRKAR1A mutations are nonsense mutations that result in the mutant protein being undetectable, no genotype-phenotype correlations are generally observed. Cutaneous lesions (lentigines, melanocytic nevi, and myxomas), although minimal in clinical impact, are the most common and occasionally specific findings supporting early diagnosis.

Carney syndrome type 2 involves a mutation of the CNC2 gene (Carney complex type 2 gene; gene locus: 2p16). Further specification has not been made to date.

Skin: Multiple pigmentary disorders, especially lentigines and blue nevi, preferentially in sun-exposed areas. Acral localized cutaneous myxomas. In contrast to Peutz-Jeghers syndrome, the carriage mucosa is not affected.

Extracutaneous manifestations: Cardiac myxomas (75% of cases), pigmented nodular hyperplasia of the NNR with more or less pronounced Cushing's phenotype.

In 40% of women there are mostly asymptomatic bilateral myxoid fibroadenomas of the mammae.

Bilateral testicular tumors (large cell calcifying Sertoli cell tumors and Leydig cell tumors) develop in more than half of men. Clinically, sexual precociousness often impresses.

Less common are growth hormone secreting pituitary adenomas or pituitary somatotropic hyperplasia leading to acromegaly.

There is a tendency for thyroid tumors, including a predisposition to thyroid cancer (Kamilaris CDC et al. 2019).

Cardiac surgery. Early diagnosis is important(acral myxoma with "freckles" in young adulthood) to clarify concomitant symptoms, especially myxomas on the heart, and to treat them if necessary.

Skin symptoms: If necessary, removal of cutaneous myxomas and conspicuous nevi. In case of cosmetically disturbing lentigines, covering, e.g. with Dermacolor.

1. Atherton DJ, Pitcher DW, Wells RS, McDonald DM (1980) A syndrome of various cutaneous pigmented lesions, myxoid neurofibromata and atrial myxoma: the NAME syndrome. Brit J Derm 103: 421-429
2. Burgdorf WH et al (1988) Autosomal dominant genodermatoses and their association with internal carcinomas. Dermatologist 39: 413-418
3. Carney AJ, Gordon H, Carpenter PC et al (1985) The complex of myxomas, spotty pigmentation, and endocrine overactivity. Medicine 64: 270-283
4. Handley J, Carson D, Sloan J et al (1992) Multiple lentigines, myxoid tumours and endocrine overactivity: four cases of Carney's complex. Brit J Dermatol 126: 367-371
5. Hoffmann U et al (2003) Usefulness of magnetic resonance imaging of cardiac and paracardiac masses. Am J Cardiol 92: 890-895.

6. Kaltsas G et al (2023) Carney Complex. In: Feingold KR et al editors. South Dartmouth (MA): MDText.com, Inc; 2000-. PMID: 25905341.

7. Kamilaris CDC et al (2019) Carney Complex. Exp Clin Endocrinol Diabetes127:156-164.
8. Li Y et al (2003) Herpes simplex virus type 1 infection associated with atrial myxoma. Am J Pathol 163: 2407-2412
9. Nishimoto K et al (2004) Surrounding muscle edema detected by MRI is valuable for diagnosis of intramuscular myxoma. Oncol Rep 11: 143-148
10. Rhodes AR et al (1984) Mucocutaneous lentigines, cardiomucocutaneous myxomas, and multiple blue nevi: the "LAMB" syndrome. J Am Acad Dermatol 10: 72-82
11. Ribbert H (1908) On the myxoma. Frankfurter Zschr Pathol 4: 30-48
12. Yuehua L et al (2003) Left atrial myxoma presenting with erythematous macules and loss of memory. Clin Exp Dermatol 28: 383-386