Heterotopic nephrogenic rests in the colon and multiple congenital anomalies: possibly related association

Parachute mitral valve: Morphology and surgical management

Background

This review aims to discuss morphology and surgical management of parachute mitral valve.

Methods

A total of 62 articles in the English language with 330 parachute mitral valve patients were retrieved from the PubMed, HighWire Press, and Cochrane Library databases using specific MeSH terms and keywords between January 2000 and December 2018. In these articles, morphology of parachute mitral valve and surgical treatment options were investigated.

Results

A non-syndromic parachute mitral valve was present in 287 patients (87.0%) and a syndromic parachute mitral valve was present in 43 patients (13.0%). A higher number of patients with a non-syndromic parachute mitral valve presented with congestive heart failure compared to syndromic ones. The patients with a non-syndromic parachute mitral valve often had mitral regurgitation, while syndromic parachute mitral valve patients often had mitral stenosis.

Conclusion

Parachute mitral valves are usually not an isolated lesion and are often characterized by a constellation of pathological changes of the mitral valve leaflets, annulus, commissures, subvalvular apparatus, and supravalvular mitral ring. Therefore, the majority of the patients need one or more surgical operations. The incidence of adverse events such as reintervention, postoperative complete heart block, and mortality is high in these patients.

Extrarenal nephroblastomatosis in children: a report of two cases

BACKGROUND

Extrarenal nephroblastomatosis is a rare entity which occurs in retroperitoneum and inguinal region predominantly. Here we report two cases of primary extrarenal nephroblastomatosis of Han Chinese in Asian in unusual locations, one is located in testis and paratestis, and the other is paraspinal cord.

CASE PRESENTATION

Patient 1 was a 19-month-old boy with a hard and nodular mass adherent to the left testis in inguinal region. Patient 2 was a 9-month-old boy with a 1 × 0.7 × 0.4 cm mass in spinal canal at the midline thoracolumbar region. Histological examinations of the two patients after operations revealed extrarenall nephroblastomatosis with multiple nephrogenic foci, composed of immature glomeruli, tubules and blastemal cells.Then the patients were closely monitored without adjuvant chemotherapy, and has been alive and well without any recurrence for >6 months.

CONCLUSIONS

Most nephrogenic rests remain subclinical, and thus, complete excision of the lesion with conservative treatment is recommended. Otherwise, nephrogenic rests are close associated with Wilms tumor and regular follow-up is required to ensure early detection of malignant transformation.

Nephroblastic Neoplasms

Nephroblastoma, or Wilms tumor, is a malignant embryonal neoplasm that is derived from nephrogenic blastemal cells, with variable recapitulation of renal embryogenesis. The pathogenesis of nephroblastoma is complex and has been linked to alterations of several genomic loci, including WT1, WT2, FWT1, and FWT2. Generally, nephroblastoma is composed of variable proportions of blastema, epithelium, and stroma, each of which may exhibit a wide spectrum of morphologic variations. Distinguishing nephroblastoma with favorable histology from tumors that exhibit anaplasia is an integral component of histologic assessment because of its prognostic and therapeutic implications. Nephrogenic rests and a special variant of nephroblastoma, cystic partially differentiated nephroblastoma, also are discussed.

Heterotopic kidney tissue in the lung of a free-living common dolphin (Delphinus delphis)

A spontaneous case of renal heterotopia involving the lung parenchyma of a free-living, adult, female common dolphin (Delphinus delphis), which was found stranded alive on the North Adriatic Sea coast of Italy, is reported in this study. The lesion, slightly visible from the macroscopic point of view, had the histologic appearance of a "foreign tissue island," which was poorly demarcated from the surrounding pulmonary tissue. Within such an island, several regularly shaped and apparently mature kidney glomeruli and tubules could be observed, with no evidence of secondary tissue reaction. To the best of our knowledge, this should be the first description of heterotopic kidney tissue occurrence in the lung of any domestic or wild animal species.

Lumbosacral Ectopic Nephrogenic Rest Unassociated With Spinal Dysraphism

Nephrogenic rests (NRs) are thought to originate from persistent nephrogenic blastema and are considered precursor lesions of Wilms' tumor (WT). These rests usually occur as perilobar and intralobar lesions in the kidney and, rarely, in ectopic sites. We report a midline lumbosacral ectopic NR in a healthy full-term newborn male with no family history of WT or WT-associated syndromes. The NR presented as a soft polypoid mass covered by normal skin. An MRI study revealed no lumbosacral spine abnormalities and no communication with the vertebral canal. The resected mass measured 3 cm and contained fat and had a central 1.2-cm solid nodule. The nodule was composed of blastema, epithelial elements (mature tubules and nephrons), and abundant stroma. No other somatic tissue elements were identified after complete microscopic examination. There are 4 cases of NRs reported in the lumbosacral area associated with spinal dysraphism, and only 2 cases, in addition to our report, unassociated with spinal abnormalities. The pathogenesis of heterotopic immature nephrogenic tissue remains a source of conjecture and speculation. If these lesions are heterotopic rests, their potential for neoplastic progression is probably quite limited, but if a monodermal teratoma, then more scrupulous clinical follow-up is warranted.