Giant fibrous hamartoma of infancy: A report of two cases and review of the literature

Advances in the Diagnosis and Management of Neonatal Sarcomas

Neonatal sarcomas comprise a heterogeneous group of rare soft tissue neoplasms that present unique diagnostic and therapeutic challenges. Recent advances in molecular profiling have improved diagnostic capabilities and reveal novel therapeutic targets. Clinical trials demonstrate differences in behavior between sarcoma subtypes that allow for better clinical management. Surgical resection has been replaced with a multimodal approach that includes chemotherapy and radiotherapy. Despite these advances, neonates with sarcoma continue to fare worse than histologically similar sarcomas in older children, likely reflecting differences in tumor biology and the complexities of neonatal medicine. This review focuses on recent advances in managing neonatal sarcomas.

Giant fibrous hamartoma of infancy: A case report

RATIONALE

Fibrous hamartoma of infancy (FHI) is a rare benign soft-tissue tumor in children with a triphasic organoid histologic appearance.

PATIENT CONCERNS

We here report a case with the largest FHI published so far. A 13-month-old boy with a rapidly growing tumor 45 cm in length and 69.3 cm in circumference of the left lower extremity was identified immediately at birth.

DIAGNOSES

The diagnosis was uncertain before the operation, although biopsy was conducted. The postoperation histological examination showed arranged spindle cells, adipose tissue, and nests of immature small cells embedded in a myxoid background, which is the characteristic triphasic histology of FHI.

INTERVENTIONS

Under general anesthesia, hip and lower extremity amputation was performed.

OUTCOMES

The patient was followed-up for 6 years and no signs of recurrence were found, suggesting a favorable prognosis, although a part of the residual tumor was present after the surgery.

LESSONS

FHI exhibits pathological and clinical characteristics. However, differential diagnosis of FHI from other soft-tissue tumors before operation remains a challenge. Thus, sometimes, aggressive therapy for the treatment of FHI might be a good choice to get a satisfactory.

Fibrous Hamartoma of Infancy in the Scrotum

Fibrous hamartoma of infancy is a solid benign tumor of the subcutis, which usually occurs within the first 2 years of life. It predominantly occurs in males, and is clinically presented as a solid, painless, well-limited subcutaneous formation, tending to grow, and in most cases without any symptoms. It occurs in various locations. The aim of this case report was to present a case of a rare tumor of infancy in the scrotal region, in an 8-month-old male infant, with a nonspecific clinical picture, suggestive of a malignant formation, thus presenting a diagnostic challenge for a doctor. The tumor was completely removed. The diagnosis was confirmed by histopathological analysis. One year after the surgical procedure, a follow-up ultrasonography examination showed no relapse.

Fibrous hamartoma of infancy: radiologic features and literature review

Background

Fibrous hamartoma of infancy(FHI) is a rare benign lesion most frequently occurring within the first year of life. So far, just over 200 cases have been reported in the English literature, in which the radiologic findings of FHI have not been fully described. Herein, 2 adult cases of FHI receiving treatment in our hospital and the published cases searched on PubMed are reviewed, with the emphasis on the discussion of the spectrum of MR findings and their histologic correlation.

Case presentation

We present two adult cases who aged 47 years and 19 years with slow growing masses beginning from their childhood in the posterior craniocervical area. On CT and MR imaging, the tumours showed as the superficially located lesions with ill-defined margins that involved the subcutaneous layer and its underlying muscles. The size of the lesions were 21.3 × 16.7 × 16 cm in case 1 and 20.2 × 19.3 × 13.6 cm in case 2. The tumours demonstrated heterogeneous intensities/signals with the adipose tissue presenting as the disperse strands or small focus of fatty intensity/signal. Parallel or whirling appearance, and dilated vessels were delineated in the cases. Contrast enhancement was administered in case 1 and marked enhancement was found.

Conclusions

The usually observed manifestation of FHI on CT and/or MR imaging is the strands of adipose/fibrous intensities traversing the lesions, with the characteristic parallel or whirling appearance in some cases. The tumours with ill-defined margins have the tendency to involve the underlying muscles. Some fibroblastic and adipocytic tumours should be ruled out in differential diagnosis.

Hamartomas of skin and soft tissue

Hamartomas are benign lesions composed of aberrant disorganized growth of mature tissues. Choristomas are similar, except that they are composed of tissues not normally found at the anatomic site in which the lesion is arising. A wide range of hamartomas and choristomas can arise in the skin and soft tissue. Some of these may cause diagnostic difficulty and potentially be mistaken for neoplasms. Some neoplasms may resemble hamaratomas. Here we review the current clinical and pathologic features of these lesions, both common and rare, and discuss how to distinguish them from other entities in the differential diagnosis.

Fibrous hamartoma of infancy: a clinicopathologic study of 145 cases, including 2 with sarcomatous features

Fibrous hamartoma of infancy is a rare soft tissue lesion of infants and young children with characteristic triphasic morphology, which typically occurs in the axilla and less commonly in other locations. We reviewed 145 cases of fibrous hamartoma of infancy from our consultation archives. Cases occurred in 106 males and 39 females (mean age-15 months; range-birth to 14 years), and involved both typical sites (eg, axilla/back/upper arm) (n=69) and unusual locations (n=76). Six were congenital. The tumors presented as subcutaneous masses and ranged from 0.4 to 17 cm (mean 3 cm). All displayed triphasic morphology, but varied widely in the relative percentages of fat, fibroblastic fascicles, and primitive mesenchyme. Hyalinized zones with cracking artifact, mimicking giant cell fibroblastoma, were present in a 44 (30%) of cases; however FISH for PDGFB gene rearrangement was negative in five tested cases. In addition to classical fibrous hamartoma of infancy, two lesions contained large sarcomatous-appearing foci with high cellularity, high nuclear grade, and brisk mitotic activity. One occurred in a 10-month-old female as a new mass in a congenital fibrous hamartoma of infancy; the other occurred as a leg mass in a 6-year-old male. ETV6 gene rearrangement was negative in the tumor from the 10-month-old female. Genomic microarray (OncoScan) showed normal molecular karyotype in eight tested cases, whereas the two tumors with sarcomatous features showed a hyperdiploid/near tetraploid molecular karyotype with copy neutral loss of heterozygosity of chromosomes 1p and 11p, and loss of 10p, chromosome 14, and a large portion of chromosome 22q (22q11.23q13.33), respectively. Follow-up (52 patients; range: 1-208 months, median: 8 months) showed only two local recurrences and no metastases. Extensive local disease in the 10-month-old female with sarcomatous-appearing fibrous hamartoma of infancy necessitated forequarter amputation. In summary, our study confirms the classic clinicopathologic features, including the triphasic morphologic appearance of most cases. In contrast to earlier studies, our series illustrates a broader histologic spectrum than previously appreciated, including its close resemblance to giant cell fibroblastoma in one quarter of cases and the rare presence of 'sarcomatous' areas, the latter providing evidence that these are complex neoplasms rather than hamartomas.

Fibrous Hamartoma of Infancy: A Firm Plaque Presenting with Hypertrichosis and Hyperhidrosis

Fibrous hamartoma of infancy (FHI) is a rare, benign, soft tissue tumor. The lesion's clinical resemblance to more aggressive soft tissue tumors of childhood makes histologic diagnosis paramount. We report a unique presentation of a FHI associated with localized hypertrichosis and hyperhidrosis.

Fibrous Hamartoma of Infancy in the Eyelid: A Rare Presentation

A 6-year-old girl presented with a left nodular mass around the punctum. Previous debulking in a similar location at 10 weeks and 8 months of age confirmed fibrous hamartoma of infancy. Pathology at the initial surgery revealed benign-appearing fibroadipose tissue, vasculature, and smooth muscle. Pathologic examination from the third debulking illustrated less fibrous trabeculae extending into increased amounts of mature-appearing adipocytes with collections of immature-appearing fibrocytes. The lesion had slight differences in pathology compared with prior surgical specimens; however, was still consistent with fibrous hamartoma of infancy. No recurrence has been reported since the last surgery.