Congenital limb reduction defects affect 1 in 1,900 babies born in the US. Limb reduction refers to the shortening or total absence of a limb or a specific segment of a limb. Congenital deficiencies of the upper limb are the most common location and comprise 58.5% of newborn limb reduction deficiencies. Longitudinal deficiencies affect the long axis of the limb and can affect one bone predominantly or can be hypoplasia or aplasia of several bones. To our knowledge, this case is a unique discussion of a baby born with longitudinal ulnar deficiency without any other commonly seen associated syndrome.

OBJECTIVE: We asked why endometrial cancer sometimes vanishes.
METHODS: A total of 454 patients diagnosed with endometrioid-type endometrial cancer (EC) (via endometrial sampling) and treated in our clinic over the past 5 years were enrolled. The patients were divided into two groups: vanishing and residual, depending on whether a tumor was detected in the postoperative hysterectomy specimen. Patient age, numbers of pregnancies and deliveries, menopausal status, systemic disease status, hemogram parameters, International Federation of Gynecology and Obstetrics (FIGO) grade, and invasion status (evident on magnetic resonance imaging [MRI]) were compared between the groups.
RESULTS: ECs vanished in 42 (9.25%) patients. The vanishing rates were 19.7% (37/187) in FIGO grade 1 patients, 2.1% (5/238) in grade 2 patients, and 0% (0/29) in grade 3 patients. The average age was lower in the vanishing than the residual group, but the premenopausal status and grade 1 tumor rates were higher (both p < 0.001). An absence of invasion (as revealed by MRI) was more common in the vanishing group (p < 0.001). No recurrence developed in the vanishing group, but recurrences were noted in 3.3% (14/412) of the residual group. There were no significant between-group differences in any of the numbers of pregnancies or births, systemic disease status, or hemogram parameters (all p > 0.05).
CONCLUSIONS: Vanishing EC is more likely in premenopausal women with endometrioid grade 1 EC (as revealed by endometrial biopsy) who lack myometrial invasion on MRI.

UNASSIGNED: Gorham-Stout disease (GSD), a fibro-lymphovascular entity in which tissue replaces the bone leading to massive osteolysis and its sequelae, rarely leads to spinal deformity/instability and neurological deficits. Here, we report a 12-year-old female who was diagnosed and treated for GSD.
UNASSIGNED: A 12-year-old female presented with back pain, and the inability to walk, sit, or stand attributed to three MR/CT documented L2-L4 lumbar vertebral collapses. Closed biopsies were negative. However, an open biopsy diagnosed GSD. She underwent a dorsal-lumbar-to-pelvis fusion (i.e., T5-T12 through L5/S1/S2) using multilevel pedicle screw/rod stabilization and human leukocyte antigens (HLAs) matched allograft (i.e. from her father). Postoperatively, she was treated with \"off-label\" teriparatide injections, bisphosphonates, and sirolimus. Four years later, while continuing the bisphosphonate therapy, she remained stable.
UNASSIGNED: Surgical multirod stabilization from T5 to S2, supplemented with HLA compatible allograft, and multiple medical \"off-label\" therapies (i.e., teriparatide, sirolimus, and bisphosphonates) led to a good 4-year outcome in a 12-year-old female with GSD.

BACKGROUND: A congenital lung malformation (CLM) that is diagnosed on prenatal ultrasound exam may subsequently become undetectable on later scans, a \"vanishing\" CLM.
OBJECTIVE: The purpose of our study is to characterize the prenatal natural history and postnatal outcomes of \"vanishing\" lesions treated at our institution.
METHODS: We performed a retrospective chart review of 107 patients diagnosed prenatally with CLM at our institution. Comparisons were made using Kruskal-Wallis or t-test for continuous variables and Fisher\'s exact test or Chi-Square test for categorical variables. Multivariable analysis using logistic regression was performed.
RESULTS: Of the 104 patients, 59 (56.7%) had lesions that became sonographically undetectable on serial ultrasound scans. Patients with lesions that vanished prenatally tended to need less Neonatal Intensive Care Unit (NICU) admission at birth (persistent CLM: 54.8%vs vanished CLM: 28.8%), decreased need for supplemental O2 at birth (persistent CLM: 31.0%vs vanished CLM: 11.9%), and decreased delay in feeds (persistent CLM: 26.2%vs vanished CLM: 8.5%) compared to those with persistent CLM. After multivariate analysis controlling for maternal steroid administration and sex, admission to NICU maintained a slight statistical significance, with patients in the vanishing CLM group 2.5 times less likely to be admitted to the NICU. None of our patients whose lesions vanished prenatally required mechanical ventilation. Eighty-six patients underwent postnatal computed tomography (CT) chest. Only 2 patients had lesions that regressed on postnatal CT.
CONCLUSIONS: Lesions that vanish on prenatal imaging may be associated with improved clinical outcomes. The rate of true regression at our institution was as low as 2.3%.

BACKGROUND: Vanishing brain tumor is defined as spontaneously disappearing or decreasing of the initial brain mass volume to ≤ 70% before establishing the definitive diagnosis. The condition is rare and can be attributed to different factors. The exact mechanism is under debate, but the increasing rate and accuracy of neuroimaging studies and occurrence of similar scenario in other pathologies rather than brain tumors can be of particular importance in finding vanishing brain lesions.
METHODS: We present two unusual cases of congenital brain masses which underwent spontaneous shrinkage within the first months of life.
CONCLUSIONS: The condition is scarcely observed in congenital brain masses. As congenital brain lesions are distinct entities with peculiar characteristics, this rare phenomenon may reflect different aspects in this age group.

BACKGROUND: Approximately 30% of patients with colorectal cancer develop colorectal liver metastases (CRLM). CRLM that become undetectable by imaging after chemotherapy are called disappearing liver metastases (DLM). But a DLM is not necessarily equal to cure. An increasing incidence of patients with DLM provides surgeons with a difficult dilemma: to resect or to not resect the original sites of DLM? The aim of this review was to investigate to what extent a DLM equates a complete response (CR) and to compare outcomes.
METHODS: This review was conducted in accordance with the PRISMA guidelines and registered in Prospero (registration number CRD42017070441). Literature search was made in the PubMed and Embase databases. During the process of writing, PubMed was repeatedly searched and reference lists of included studies were screened for additional studies of interest for this review. Results were independently screened by two authors with the Covidence platform. Studies eligible for inclusion were those reporting outcomes of DLM in adult patients undergoing surgery following chemotherapy.
RESULTS: Fifteen studies were included with a total of 2955 patients with CRLM. They had 4742 CRLM altogether. Post-chemotherapy, patients presented with 1561 DLM. Patients with one or more DLM ranged from 7 to 48% (median 19%). Median DLM per patient was 3.4 (range 0.4-5.6). Patients were predominantly evaluated by contrast-enhanced computed tomography (CE-CT) before and after chemotherapy, with some exceptions and with addition of magnetic resonance imaging (MRI) in some studies. Intraoperative ultrasound (IOUS) was universally performed in all but two studies. If a DLM remained undetectable by IOUS, this DLM represented a CR in 24-96% (median 77.5%). Further, if a DLM on preoperative CE-CT remained undetectable by additional workup with MRI and CE-IOUS, this DLM was equal to a CR in 75-94% (median 89%). Patients with resected DLM had a longer disease-free survival compared to patients with DLM left in situ but statistically significant differences in overall survival could not be found.
CONCLUSIONS: Combination of CE-CT, MRI, and IOUS showed promising results in accurately identifying DLM with CR. This suggests that leaving DLM in situ could be an alternative to surgical resection when a DLM remains undetectable by MRI and IOUS.

Advances in systemic chemotherapy have resulted in a significant increase in the reported response rates of colorectal liver metastases (CRLM) over time. Although radiologic response is usually prognostic of favorable outcomes, complete shrinkage of CRLM after chemotherapy, namely \"disappearing liver metastases\" (DLMs) poses significant therapeutic dilemmas. A systematic review of the literature was conducted to evaluate the existing evidence on the imaging and management of patients with DLMs using the PubMed (Medline), Embase and Cochrane library through December 21st, 2018. The following algorithm was used: \"(disappearing OR vanishing OR missing OR (residual tiny)) AND ((liver OR hepatic) AND (metastasis OR metastases OR metastatic OR secondary)).\" From the 225 records retrieved, 15 studies were finally deemed eligible. A total of 479 patients with DLMs with a median age of 59.5 years (range, 30-83) were identified. Median number of DLM per patient ranged from 1 to 8.8. Median size of LMs prior to chemotherapy was 1.07 cm (range 0.3-3.5). The systemic treatment used to achieve DLMs included systemic chemotherapy alone (only 2 studies) or in combination with targeted agents (11 studies). The median number of chemotherapy cycles in the included studies was 7.8 (range 6-12). Identified factors predisposing to the development of DLM were small size (<2 cm), increased number of treatment cycles, oxaliplatin-based therapy, increased number of CRLM (≥3) and synchronous CRLM. Baseline and preoperative MRI with iv contrast showed the highest sensitivity for DLM detection. Fiducial placement facilitated pre- and intra-operative identification of DLM. Although resection of DLM decreased the local recurrence risk, there was no clearly demonstrated survival benefit after resecting all sites of disappearing lesions. Future randomized clinical trials are highly encouraged to provide strict, evidence-based recommendations for the treatment of patients with DLM.

BACKGROUND: Meningiomas are common intracranial neoplasms of undetermined etiology. Accelerated growth during episodes of elevated serum estrogen and progesterone have been demonstrated in pregnant patients, as exhibited by an overexpression of estrogen or progesterone on immunohistochemical analysis. This case report and literature review describe a case of complete meningioma regression in a postpartum patient.
METHODS: A 23-year-old female presented at 37 weeks of pregnancy with 1-month history of fluctuating severe left-sided headaches, periodic blurry vision, nausea, and vomiting. She had 2 previous pregnancies without complication. Magnetic resonance imaging revealed a dural-based, heterogeneously enhancing mass along the left tentorium, just posterior to the transverse sinus, with supratentorial extension and surrounding edema. Differential diagnoses included meningioma versus hemangioma versus hemangiopericytoma. The patient followed up with neurosurgery 1 month after delivery. She had continued left-sided headaches but no longer complained of visual changes. A postpartum surgical resection via left occipital and suboccipital craniotomy was planned. Approximately 1 month later (now about 3 months after delivery) a repeat magnetic resonance imaging demonstrated a marked decrease in meningioma size, and the previously seen edema had resolved. In light of the sudden disappearance of the meningioma, no further surgical intervention was pursued.
CONCLUSIONS: Because meningioma shrinkage or disappearance may occur after pregnancy, repeat imaging is advised as part of a preoperative evaluation. In addition, it is possible that an undetermined amount of meningioma removal surgeries may be avoided with further research into monitoring hormone levels connected to meningioma growth.

UNASSIGNED: Of all parotid gland tumors, only oncocytoma has been reported to appear isointense to the parotid gland, namely vanishing, on fat-saturated T2 and T1 postcontrast gadolinium-enhanced magnetic resonance imaging (MRI). The purpose of this study was to evaluate vanishing of parotid tumors on conventional MRI with and/or without postcontrast gadolinium-enhancement and on diffusion weighted imaging (DWI).
UNASSIGNED: In 8 of 51 patients, ten parotid gland tumors had homogeneously enhanced lesions and were retrospectively analysed. Comparisons of signal intensity between those parotid tumors and parotid glands and evaluations of vanishing were performed on T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), fat-suppressed T2WI (FS-T2WI), postcontrast gadolinium-enhanced T1WI (CE-T1WI) and fat-suppressed CE-T1WI (FS-CE-T1WI), DWI as well as apparent diffusion coefficient (ADC).
UNASSIGNED: Ten parotid gland tumors consisted of five Warthin tumors, two pleomorphic adenomas, two parotid carcinomas (small cell carcinoma and adenoid cystic carcinoma) and one oncocytoma. All tumors showed hypointensity on T1WI and hyperintensity on DWI. Nine of ten tumors showed vanishing on the other MR sequences. All Warthin tumors showed vanishing on FS-T2WI, FS-CE-T1WI and the ADC map. One oncocytoma showed vanishing on FS-T2WI and the ADC map and hyperintensity on FS-CE-T1WI. All pleomorphic adenomas showed vanishing on T2WI and CE-T1WI. One adenoid cystic carcinoma showed vanishing only on CE-T1WI.
UNASSIGNED: Vanishing of parotid tumors can be observed not only on FS-T2WI and FS-CE-T1WI but also on T2WI, CE-T1WI and ADC mapping.

We present a severe case of vanishing gastroschisis resulting in intrauterine death with post mortem examination findings. Gastroschisis is defined as a full thickness paraumbilical abdominal wall defect associated with evisceration of fetal intestine. It is almost always right-sided. Vanishing gastroschisis is an extremely rare form of gastroschisis that results in short bowel syndrome due to exteriorized bowel disconnected from the lumen of the rest of the bowel proximally as well as distally in association with partial or complete closure of the abdominal wall. This case is only the second published case of vanishing gastroschisis resulting in intrauterine fetal death including post mortem examination findings. It highlights the importance of being aware of this rare form of gastroschisis and provides insights regarding pathogenesis, ultrasound surveillance, and antenatal counseling.