An unusual tumour: Hamartoma of mature cardiac myocytes

Hamartoma of Mature Cardiac Myocytes: Systematic Review

BACKGROUND

While primary cardiac tumors are rare, it has been increasingly recognized due to improvement in screening measures. However, the hamartoma of mature cardiac myocytes has been underrecognized compared to other cardiac tumors, such as cardiac myxomas and papillary fibroelastomas, and is still potentially associated with critical consequences such as sudden death. This systematic review aims to summarize the evidence regarding the hamartoma of mature cardiac myocytes and characterize the presentations and symptoms for clinicians.

METHODS

Following the PRISMA statement, we searched MEDLINE and EMBASE for all peer-reviewed articles using keywords including "hamartoma of mature cardiac myocytes" from their inception to January 2nd, 2023.

RESULTS

We included 25 articles, including 34 cases, in this systematic review. Patients with hamartoma of mature cardiac myocytes commonly presented with nonspecific symptoms such as dyspnea (35.3%), although a few presented with sudden death and syncope. The left ventricle was the common site of origin (41.2%), followed by the right atrium and ventricle. Surgery was commonly pursued for diagnosis and treatment, while a few required cardiac transplants (8.8%), and 29.4% were diagnosed with autopsy or expired.

CONCLUSION

Hamartoma of mature cardiac myocytes is a potentially underrecognized primary cardiac tumor associated with treatable yet potentially critical consequences. Given the challenges of differentiating it from malignancy such as angiosarcoma, multimodal imaging needs to be utilized to pursue a diagnosis. Future studies are warranted to develop a noninvasive diagnosis mode for cardiac tumor.

Intraspinal choristoma in the lumbar region: A case report

RATIONALE

Intraspinal choristoma is a relatively uncommon intervertebral canal tumor. Prior to our reports, only 2 cases of intraspinal choristoma had been reported. Because this disease is not common and looks like a mass of fatty tissue on the magnetic resonance imaging (MRI), intraspinal choristoma can be easily misdiagnosed as teratomas or lipomas (like the case of this article presenting) without a pathology report. So if a lumber intraspinal lesion is discovered in a clinical examination, intraspinal choristoma should be considered as a differential diagnosis. We present a case of intraspinal choristoma that is unlike any other reported case.

PATIENT CONCERNS

A 35-year-old woman with left lower extremity hypoesthesia and burning-like pain in the lumbar region for 1 month visited the local hospital for plain lumbar spine MRI. The patient was diagnosed with a lumbar space-occupying lesion. A second plain lumbar spine MRI scan and a MRI scan with enhancement were performed in our hospital to confirm the presence of a congenital lipoma in the spinal canal. A postoperative biopsy of the lumbar spinal mass indicated that the mass was an intraspinal choristoma located in the spinal canal.

DIAGNOSIS

Intraspinal choristoma.

INTERVENTION

The lesion was surgically removed, and follow-up plain and enhanced MRI images of the patient's lumbar spine were obtained.

OUTCOMES

After surgery, the patient no longer experienced the burning pain in her lumbar region or the left lower extremity hypoesthesia when the patient was discharged. And there was no evidence of recurrence 2 years after the surgery.

LESSONS

The MRI presentation of intraspinal choristoma is similar to intraspinal lipoma. Therefore, a pathological assessment is critical to provide an accurate diagnosis.

Atypical Presentation of Right Ventricular Cardiac Hamartoma in a Young Man

Cardiac tumors in adults are exceedingly rare and usually benign. We describe a 29-year-old man with a previous diagnosis of interventricular septal hypertrophy who presented with increasing severity of dyspnea and fatigue. Work-up revealed a 4.9 × 3.7 cm mass at the base of the interventricular septum. Biopsy revealed a benign cardiac hamartoma atypically located in the right ventricle, and the mass was resected via right ventriculotomy.

A Rare Case of Cardiac Mesenchymal Hamartoma and Comprehensive Review of the Literature With Emphasis on Histopathology

Hamartomas are primary, benign neoplastic lesions that most commonly derive from a single variably differentiated cell lineage. Here, we report an unusual case of a cardiac hamartoma. A 62-year-old woman presented with chest pain and palpitations. Serial imaging revealed a large slowly growing and highly vascularized left ventricular mass, which required surgical resection. Microscopically, the lesion was composed of nodular fibrovascular proliferation with haphazardly embedded muscle bundles and peripheral calcifications. Immunohistochemical studies revealed prominent muscle-specific actin positive and smooth muscle actin positive muscle fiber bundles within a disorganized fibrovascular stroma. This characterization is most consistent with cardiac mesenchymal hamartoma. Relevant differential diagnoses for this lesion include hamartoma of mature cardiac myocytes (HMCMs) and intramuscular hemangioma. The prominent smooth muscle differentiation of muscle bundles was incompatible with defining features of HMCM. Absence of S100-positive nerve and mature adipose cells distinguished this lesion from the recently defined, heterogeneous cardiac mesenchymal hamartoma. Forty-seven cases of cardiac hamartoma reported from 1970 to 2020 were reviewed to provide histopathologic context.