The Mysterious Organ. Spectrum of Focal Lesions within the Splenic Parenchyma: Cross-Sectional Imaging with Emphasis on Magnetic Resonance Imaging

Percutaneous Computed Tomography (CT) Fluoroscopy-Guided Biopsy of the Spleen Using Fibrin Glue as a Sealant

Some authors consider the risk of bleeding an absolute contraindication to percutaneous image-guided splenic puncture. While splenic punctures are mainly performed at specialized centers, no technique for the closure of the puncture tract has been broadly established. The aim of this study was to investigate the effectiveness and safety of a percutaneous image-guided biopsy of the spleen using fibrin glue to plug the tract. A total of 27 requests for splenic image-guided interventions were identified between 2010 and 2021 and considered for inclusion in our retrospective single-center study. Seven patients needed to be excluded, which left twenty patients who underwent a percutaneous computed tomography (CT) fluoroscopy-guided biopsy of a splenic lesion during this period. In all patients, a 17G coaxial needle with an 18G core biopsy needle was used. Diagnostic adequacy and accuracy were evaluated, and complications were classified using the CIRSE classification system for adverse events. Diagnostic adequacy was 100% (20/20), and a median of four samples were collected. Diagnostic accuracy was 80% (16/20). The four off-target samples included one inconclusive finding and three samples of regular spleen tissue. The overall complication rate was 5% (1/20). No mild (grade 1-2) or moderate (grade 3-4) complications occurred. One severe (grade 5-6) complication occurred. Although controversial and potentially high-risk, diagnostic percutaneous biopsies of the spleen appear to be relatively safe with the use of fibrin glue to seal the tract.

Acoustic Radiation Force Impulse (ARFI) Elastography of Focal Splenic Lesions: Feasibility and Diagnostic Potential

PURPOSE

Nontraumatic focal splenic lesions (FSL) are rare, and the need for tissue diagnosis must be weighed against the very high risk of bleeding after a splenic biopsy. The aim of this study was to explore the feasibility and diagnostic potential of acoustic radiation force impulse (ARFI) elastography as a noninvasive method for different benign and malignant FSLs. No human studies on the elastographic characteristics of FSL exist.

METHODS

This was a retrospective analysis of 34 patients with FSLs, who underwent abdominal B-mode ultrasound (B-US), contrast-enhanced ultrasound (CEUS), and standardized ARFI examinations between October 2021 and December 2022 at our university hospital. The inclusion criteria were: (i) FSL size ≥ 1 cm; (ii) 10 valid ARFI measurements of the FSL, as well as of the normal splenic parenchyma (NSP) as an in vivo reference; and (iii) diagnostic confirmation of FSL etiology based on histological examination (8/34; 23.5%) or clinical evaluation, which included a clinical and sonographic follow-up (FU), CEUS morphology, and/or morphology on cross-sectional imaging (26/34; 76.5%). CEUS was performed on all patients and the FSLs were classified according to the current guidelines; cross-sectional imaging was available for 29/34 (85.3%). The mean FU duration was 25.8 ± 30.5 months. The mean ARFI velocity (MAV) of the FSL (MAVL), the NSP (MAVP), and the ratio of the MAVL to the MAVP (MAVL/P) were calculated and compared.

RESULTS

Of the 34 FSLs, 13 (38.2%) were malignant (mFSL) and 21 (61.8%) were benign (bFSL). The MAVL of all 34 FSLs (2.74 ± 0.71 m/s) was lower than the MAVP (3.20 ± 0.59 m/s), p = 0.009, with a mean MAVL/P ratio of 0.90 ± 0.34. No significant differences in the MAVL were observed between the mFSL (2.66 ± 0.67 m/s) and bFSL (2.79 ± 0.75 m/s). There were also no significant differences between the MAVP in patients with mFSL (3.24 ± 0.68 m/s) as compared to that in the patients with bFSL (3.18 ± 0.55 m/s). Likewise, the MAV L/P ratio did not differ between the mFSL (0.90 ± 0.41 m/s) and bFSL (0.90 ± 0.30 m/s) groups.

CONCLUSION

ARFI elastography is feasible in evaluating the stiffness of FSLs. The lesions' stiffness was lower than that of the NSP, regardless of the FSL etiology. However, differentiation between benign and malignant FSL with the help of this elastographic method does not appear possible. Larger prospective studies are needed to validate these findings.

Evaluation of cross-sectional imaging features that aid in the differentiation of benign and malignant splenic lesions

PURPOSE

This study aimed to investigate the role of cross-sectional imaging in differentiating between benign and malignant splenic lesions based on various imaging features.

METHODS

Database of imaging reports from January 2015 to December 2017 were searched dedicatedly for "spleen" or "splenic" terms to identify patients with splenic lesions found either on CT or MRI. The study cohort consisted of patients who had available histological reports or had follow-up imaging for a minimum of one year. Patients were categorized into the benign subcohort if they did not have a history of extra-splenic malignancy, and had a splenic lesion(s) falling into one of these categories: benign histopathology on biopsy, stable size and enhancement, or decreased size on follow-up imaging. Those who had malignant histopathology on biopsy were included in the malignant subcohort. Various morphologic features and enhancement patterns of these lesions were carefully reviewed by two radiologists who were blinded to the final histopathologic diagnosis.

RESULTS

We identified 161 patients (54 % males, mean age ± SD = 59.7 ± 15.4) including 124 (77 %) in the benign and 37 (23 %) in the malignant subcohort. Benign lesions were more likely to be cystic (21.7 % vs 2.7 %, p < 0.001), homogenous (59.7 % vs. 29.7 %, p = 0.001) and to demonstrate well-defined borders (69.3 % vs. 29.7 % p= <0.001). Malignant lesions had significantly larger diameter (median size: 15 vs 11 mm, p = 0.03). Restricted diffusion was not seen in any of the benign lesions; however, 50 % of malignant lesions demonstrated restricted diffusion (p = 0.003). Features such as lesion distribution, presence of calcification, splenomegaly and number of lesions were not significantly different between benign and malignant lesions.

CONCLUSION

Smaller lesion diameter, well-defined border and homogeneity favor benign nature of splenic lesions while restricted diffusion should raise suspicion for malignancy.

Percutaneous Image-Guided Biopsy of the Spleen: Experience at a Single Tertiary Care Center

PURPOSE

The purpose of this study is to assess the complication rate of percutaneous image-guided biopsy of the spleen at our institution and to evaluate for variables associated with complication rate.

METHODS

This is a Research Ethics Board approved retrospective study of consecutive patients who underwent image-guided biopsy of the spleen at our institution from January 2010 to November 2019. Complications, imaging findings, and pathologic diagnosis were reviewed. Complications (major and minor) were classified per Society of Interventional Radiology Guidelines, and complication rate was calculated. Logistic regression was applied to determine factors associated with complications. Diagnostic yield was calculated.

RESULTS

In all, 55 patients (28 female) underwent splenic biopsy using ultrasound guidance. The most common indication was possible lymphoma in 41 (71.7%) patients followed by query metastasis 18 (31.5%) patients. Core biopsies (18 g/20 g) were done in 53 (92%) cases, and fine-needle aspiration (22 g) was performed in 4 (8%). The median number of samples collected was 4 (range: 2-9). The results were diagnostic in 54 cases (94.7%, 95% confidence interval [CI]: 88.7-100.0). There were 12 (21%, 95% CI: 10.1-31.9) patients with minor complications and 2 (3.5%, 95% CI: 0.0-8.4) with major complications (2 splenic bleeds requiring embolization, no splenectomy, or deaths). No variables (needle size, lesion size, and number of passes) were associated with complication rate.

CONCLUSION

Percutaneous image-guided biopsy of the spleen at a single tertiary care institution demonstrates major complication rate comparable to that in the literature with no variables associated with complication rate; there were no cases of splenectomy or death.

5-Year survival after splenectomy in a patient with recurrent cutaneous melanoma: a case report

OBJECTIVE

Splenic metastases of melanoma are uncommon and generally part of a disseminated disease with a poor prognosis. In case of solitary visceral metastasis, surgical resection often remains an effective treatment. This case describes a long-term survival after splenectomy for a recurrent melanoma.

METHODS

We present a 55-year-old female with a solitary splenic metastasis. Her medical history revealed a melanoma of the foot in 2007 and an in-transit metastasis in 2011. A PET-CT revealed in 2012 the presence of a small aspecific lesion in the spleen. Close follow-up was chosen. Since PET-CT and MRI showed a progressive lesion, a laparoscopic splenectomy was performed.

RESULTS

Histological report confirmed the diagnosis of a metastatic lesion. Sixty months after the first radiographic evidence of the splenic metastasis, follow-up revealed no signs of residual disease.

CONCLUSIONS

Although current systemic approaches demonstrate to provide clinically important benefit, patients with oligometastatic disease should be evaluated for surgical metastasectomy. A laparoscopic approach for splenic metastasis is shown to be a safe treatment. This disease-free survival of 60 months in a patient with a history of an in-transit metastasis has not been published before. A splenectomy for a solitary metastasis could prolong the survival, even in a recurrent melanoma.

An uncommon presentation of metastatic melanoma: a case report

Metastases to the spleen are rare and are generally part of a multi-visceral metastatic disease. The most common sources of splenic metastases include breast, lung and colorectal malignancies as well as melanoma and ovarian carcinoma. Solitary splenic metastasis is very uncommon. We present a case of a 44-year-old man who presented at our department for gallstones symptoms. He had a past medical history of neck cutaneous melanoma (T3bN0M0--Stage IIb). He had not attended follow-up schedule for personal reasons. However, abdominal ultrasound revealed the presence of a solitary solid lesion in the spleen. Preoperative workup was completed with CT scan that confirmed the presence of a large splenic lesion with subcapsular fluid collection, also compatible with a post-traumatic lesion.Preoperative findings could not exclude malignancy and patient was therefore submitted to surgery. At laparoscopy, a condition of peritoneal melanosis was present. Splenectomy was carried out. Histological report confirmed the peritoneal melanosis and the diagnosis of metastatic spleen lesion from melanoma. Patient was observed, but died of metastatic disease 14 months after surgery. Splenic metastases are uncommon. Isolated metastases from melanoma are rare and could be found several months after primary diagnosis of melanoma. Surgery remains the most effective treatment, especially for metachronous disease, offering the best chance of long-term survival. Prognosis remains poor, as metachronous disease is indicative of aggressive widespread of the disease.