Technical report. Intra-operative ultrasound-guided needle localization for impalpable testicular lesions

Diagnosis and management of indeterminate testicular lesions

The sophistication and accessibility of modern-day imaging result in frequent detection of small or equivocal lesions of the testes. Traditionally, diagnosis of a testicular lesion with any possibility of malignancy would usually prompt radical orchidectomy. However, awareness is growing that a substantial proportion of these lesions might be benign and that universal application of radical orchidectomy risks frequent overtreatment. Given the potentially profound effects of radical orchidectomy on fertility, endocrine function and psychosexual well-being, particularly in scenarios of an abnormal contralateral testis or bilateral lesions, organ-preserving strategies for equivocal lesions should be considered. Image-based active surveillance can be applied for indeterminate lesions measuring ≤15 mm with a low conversion rate to surgical treatment. However, these outcomes are early and from relatively small, selected cohorts, and concerns prevail regarding the metastatic potential of even small undiagnosed germ cell tumours. No consensus exists on optimal surveillance (short interval (<3 months) ultrasonography is generally adopted); histological sampling is a widespread alternative, involving inguinal delivery of the testis and excisional biopsy of the lesion, with preoperative marking or intraoperative ultrasonographic localization when necessary. Frozen section analysis in this context demonstrates excellent diagnostic accuracy. Histological results support that approximately two-thirds of marker-negative indeterminate solitary testicular lesions measuring ≤25 mm overall are benign. In summary, modern imaging detects many small indeterminate testicular lesions, of which the majority are benign. Awareness is growing of surveillance and organ-sparing diagnostic and treatment strategies with the aim of minimizing rates of overtreatment with radical orchidectomy.

Diagnostic yield and safety of ultrasound-guided percutaneous testicular biopsies in children

BACKGROUND

Traditionally, testicular biopsy is performed using an open surgical approach. Ultrasound-guided percutaneous biopsy is a less invasive alternative and can be performed in children.

OBJECTIVE

The aim of this study is to report our technique and to assess the diagnostic accuracy and safety of ultrasound-guided percutaneous biopsy of testicular masses in children.

MATERIALS AND METHODS

This is a 16-year retrospective review of ultrasound-guided percutaneous testicular biopsies at a single pediatric hospital.

RESULTS

We performed nine ultrasound-guided testicular biopsies in 9 patients (median age: 3 years, range: 4 months-11 years; median weight: 20.9 kg, range: 8.4-35 kg; median volume of testicular lesion biopsied: 4.4 mL, range: 1.2-17 mL). A percutaneous co-axial technique was used for 5/9 biopsies with absorbable gelatin sponge tract embolization performed in 4 of those biopsies. A non-co-axial technique was used in 4/9 biopsies. A median of three cores, range 2-6, were obtained. The diagnostic yield was 89% with one biopsy yielding material suggestive of, but insufficient for, a definitive diagnosis. The most common histological diagnosis was leukemic infiltration, occurring in 6/9 biopsies. Of the remaining three biopsies, one biopsy was suggestive of, but not confirmatory for, juvenile granulosa cell tumor and two biopsies confirmed normal testicular tissue; the long-term follow-up of which demonstrated normal growth and no lasting damage. There was one (clinically insignificant) complication out of nine biopsies (11%, 95% confidence interval 0-44%): a mild, self-resolving scrotal hematoma.

CONCLUSION

Ultrasound-guided testicular biopsy can be performed safely in children as an alternative to open surgical biopsy, with a high diagnostic yield and low complication rate.

What Is the Malignant Potential of Small (<2 cm), Nonpalpable Testicular Incidentalomas in Adults? A Systematic Review

CONTEXT

Unlike palpable lumps, a large number of nonpalpable testicular lesions found incidentally at ultrasound in asymptomatic postpuberal males are either benign tumours or non-neoplastic lesions. The prevalence of malignancy, however, is appraised based on small case series. Dedicated studies report a large number of patients, and systematic review articles are lacking.

OBJECTIVE

This systematic review is aimed to assess, from the analysis of the pooled data of the available literature, the incidence of benign tumours, malignant tumours, and non-neoplastic lesions, and to identify predictive characteristics for malignancy.

EVIDENCE ACQUISITION

A systematic review of PubMed, Scopus, Google Scholar, Turning Research Into Practice (TRIP) database, and the Cochrane Library was conducted on January 6, 2022, according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Studies were retrieved reporting on adult asymptomatic men, with single, incidentally identified small testicular lesions, either fertile or infertile, with negative tumour markers and without specific risk factors for malignancy. Lesions ≤20 mm were considered small. Seventy-four studies were selected for inclusion in this analysis. Twenty-six additional publications have been retrieved by the bibliography quoted in the selected articles.

EVIDENCE SYNTHESIS

Pooled data of 1348 lesions in 1348 patients were collected. Of these lesions, 408 could be retrieved individually, 44.6% were benign, 27.2% were malignant, and 20.8% were non-neoplastic. Virtually all lesions <3 mm and 86.6% of lesions <5 mm were benign. Lesions >10 mm have a 38.14% probability of being benign. Hyperechoic lesions are likely benign. Fertility status does not affect the risk of malignancy.

CONCLUSIONS

Very small (<3 mm) and small (<5 mm) incidentally detected testicular lesions in asymptomatic postpuberal men with normal tumour markers could be frequently benign. More prospective studies are needed to better support this finding. Management strategies should be developed for these patients to reduce overtreatment.

PATIENT SUMMARY

Small testicular lesions are incidentally founded at ultrasound. It is not easy to distinguish a benign lesion from a malignant one. Results of this study are reporting a higher incidence of benign lesions with a diameter of <5 mm. More studies are needed to better understand the biology and the management strategy for small testicular lesions.

Prevalence and Management of Incidental Testicular Masses-A Systematic Review

Management of incidentally diagnosed small testicular masses (STM) is controversial. Although there is the risk of malignancy, it might be realistic to safely seek preservation of testicles bearing benign masses. This study aims to systematically evaluate the evidence regarding prevalence of STMs, their benign or malignant histology and their management. We conducted a systematic literature search for studies reporting small or incidental testicular masses and their management by radical orchiectomy, testis sparing surgery (TSS) or ultrasound (US) surveillance. We initially screened 2126 abstracts and from these, 57 studies met the inclusion criteria. Testicular masses were detected in 1.74% of patients undergoing US examination. Regarding STMs removed by surgery, 41.12% were benign. Intraoperative frozen section examination (FSE) is a reliable tool to discriminate between benign and malignant testicular masses (average 93.05% accuracy), supporting TSS. Benign lesions were associated with smaller diameter (<1 cm 68.78% benign), were often hypoechoic and exhibited regular margins on US. Conclusions: Small testicular masses are often benign. Clinical and US patterns are not accurate enough for including patients in surveillance protocols and TSS paired with FSE is pivotal for precluding the removal of testicles bearing benign lesions. Future research might unveil new imaging tools or biomarkers to support clinical management.

Incidental Findings and How to Manage Them: Testis- A WFUMB Position Paper

Testicular incidentalomas are non-palpable, asymptomatic lesions, most frequently detected on ultrasound examinations. Each incidentaloma should undergo a standardized diagnostic workup to exclude malignancy and recognize other potentially significant non-malignant conditions that may first present with an incidental finding on scrotal ultrasound. This position statement of the World Federation of Ultrasound in Medicine and Biology (WFUMB) summarizes the available evidence on management of testicular incidentalomas and describes efficient management strategies with particular reference to the role of ultrasound techniques.

Current status of percutaneous testicular biopsy for focal lesions

OBJECTIVE

The purpose of this review is to evaluate the current role of percutaneous testicular biopsy in the diagnosis of focal testicular lesions.

CONCLUSION

Percutaneous testicular biopsy can be either fine needle aspiration biopsy or trucut core needle biopsy. It is a well-tolerated and effective procedure useful in small testicular lesions, multifocal lesions, hematological malignancies, and focal lesions in single testis.

Testis-Sparing Surgery in Small Testicular Masses Not Suspected to Be Malignant

Fifteen patients with small testicular masses not suspected to be malignant were included in the study, and permanent and frozen section analyses were evaluated. As a result frozen analysis, preoperative externalization of the suspected malignancy with a physical examination, ultrasonographic evaluation, and serum tumor marker analysis were concluded as key points for accurate decision making between TSS and radical orchiectomy.

BACKGROUND

We aimed to determine the safety, efficacy, and the concordance of permanent and frozen section analysis (FSA) of testis-sparing surgery (TSS) in patients who had small testicular masses that were not suspected to be malignant.

PATIENTS AND METHODS

Fifteen patients who underwent TSS were included in the study. TSS was performed for the patients who had testicular lesions <25 mm and testicular lesion volume <30% of the whole testis. All patients had normal serum tumor marker levels and ultrasonographic evaluation did not indicate malignancy. Surgery was performed via an inguinal approach with temporary cord occlusion and FSA of the lesions. Benign findings allowed for TSS, and cancer prompted total orchiectomy.

RESULTS

The mean patient age was 25.33 (range, 20-36) years. The predominant complaint was swelling (9 patients). The mean lesion diameter was 16 mm (range, 5-26 mm). Fourteen of all cases (93%) had benign pathology and underwent TSS. Only 1 patient, whose FSA revealed malignant formation, underwent radical orchiectomy. Final pathology of this patient was seminoma. Complete histopathologic concordance was observed between the results of frozen and permanent sections. TSS was performed with no intra- or postoperative complications. After a mean follow-up of 23 months (range, 6-44 months) all patients, except 3 who were lost to follow-up, were free of disease.

CONCLUSION

The main key points for accurate decision-making between TSS and radical orchiectomy are intraoperative FSA and preoperative externalization of possible suspected malignancy with physical examination, ultrasonographic evaluation, and serum tumor marker analysis.

Intraoperative injection of (99mm)Tc- nanocolloid for localization of nonpalpable intratesticular tumours in organ-sparing surgery

OBJECTIVE

Radical orchidectomy is the standard treatment for malignant testis tumours. Radical orchidectomy results in androgen deprivation, infertility and impaired psychological well-being, especially in synchronous bilateral tumours, metachronous contralateral tumours or tumour in a solitary testis. According to the European Association of Urology Guidelines, if pre-operative testosterone level is normal and the tumour volume is less than 30% of the testicular volume, organ preserving surgery can be performed. For nonpalpable tumours, organ-sparing surgery needs a precise intraoperative localization with high-frequency ultrasound, especially for nonpalpable tumours.

MATHERIAL AND METHODS

We report two cases of nonpalpable intratesticular tumours successfully localised using (99mm)Tc nanocolloid injected with intraoperative US and detected with a γ-ray detection probe.

CONCLUSIONS

This method is easily reproducible and safe for the patient. This technique could guarantee complete excision of the tumour, especially if the mass is poorly delimited.

Targeted testicular excision biopsy: when and how should we try to avoid radical orchidectomy?

Small, incidental testicular lesions are often benign, but in the past have usually been treated by orchidectomy. An alternative is an operative excision biopsy, with localization by ultrasound if necessary, and characterization of the lesion by frozen section analysis. The present review summarizes the indications for the procedure, lists the likely diagnoses, and describes the technique. Frozen section is accurate for distinguishing benign from malignant lesions, testicular function is usually preserved, and there is no evidence that oncological safety is impaired. Such testis-preserving surgery is a rewarding ground for collaboration between urologists, radiologists, and pathologists.

Airborne ultrasonic phased arrays using ferroelectrets: a new fabrication approach

In this work, a novel procedure that considerably simplifies the fabrication process of ferroelectret-based multielement array transducers is proposed and evaluated. Also, the potential of ferroelectrets being used as active material for air-coupled ultrasonic transducer design is demonstrated. The new construction method of multi-element transducers introduces 2 distinctive improvements. First, active ferroelectret material is not discretized into elements, and second, the need of structuring upper and/or lower electrodes in advance of the permanent polarization of the film is removed. The aperture discretization and the mechanical connection are achieved in one step using a through-thickness conductive tape. To validate the procedure, 2 linear array prototypes of 32 elements, with a pitch of 3.43 mm and a wide usable frequency range from 30 to 300 kHz, were built and evaluated using a commercial phased-array system. A low crosstalk among elements, below -30 dB, was measured by interferometry. Likewise, a homogeneous response of the array elements, with a maximum deviation of +/-1.8 dB, was obtained. Acoustic beam steering measurements were accomplished at different deflection angles using a calibrated microphone. The ultrasonic beam parameters, namely, lateral resolution, side lobe level, grating lobes, and focus depth, were congruent with theory. Acoustic images of a single reflector were obtained using one of the array elements as the receiver. Resulting images are also in accordance with numerical simulation, demonstrating the feasibility of using these arrays in pulse-echo mode. The proposed procedure simplifies the manufacturing of multidimensional arrays with arbitrary shape elements and not uniformly distributed. Furthermore, this concept can be extended to nonflat arrays as long as the transducer substrate conforms to a developable surface.

Carefully selected intratesticular lesions can be safely managed with serial ultrasonography

OBJECTIVE

To evaluate a policy of conservative non-operative management for incidental, impalpable, < 1 cm, intratesticular pathology.

PATIENTS AND METHODS

We retrospectively reviewed all scrotal ultrasonograms within an 8-year period to identify all radiological lesions of < 1 cm within the testis. All palpable lesions and those accompanied by elevated tumour markers or disseminated malignancy were managed surgically. The remaining incidentally detected lesions were followed with a protocol of serial ultrasonography (US).

RESULTS

Of 1544 scans reviewed, 12 (0.8%) lesions suitable for observational management were identified. The mean (range) age of the patients was 54 (34-76) years. The indication for US was suspected epididymitis in five, contralateral epididymal cyst in five and infertility in two patients. The mean (range) size of the lesion was 4.9 (1.5-9.8) mm. Three anechoic lesions were consistent with intratesticular cysts, and each was followed with no change to a mean (range) follow-up of 26 (12-48) months. Eight hypoechoic lesions were followed to a mean of 34 (4-72) months, and only one showed growth on repeat US after an interval of 4 months, and was diagnosed as a 1.0-cm seminoma after orchidectomy. One hyperechoic lesion remains unchanged at 6 months of follow-up.

CONCLUSION

Supported by previous reports suggesting that most testis lesions of < 1 cm are benign, we managed a series of carefully selected intratesticular lesions conservatively, the behaviour in most being in keeping with benign pathology.

Management of incidental impalpable intratesticular masses of ≤ 5 mm in diameter

OBJECTIVE

To gain more insight into the histology of small incidental intratesticular lesions and evaluate the need for surgical management, as exploratory surgery is the only way to exclude malignancy in testicular tumours.

PATIENTS AND METHODS

Between September 2000 and April 2005, incidental intratesticular masses of < or = 5 mm in diameter were found in 20 men undergoing scrotal ultrasonography for reasons other than suspected testicular tumour. After staging, an organ-sparing approach including frozen-section analysis was used to obtain histological data.

RESULTS

The mean diameter of the detected tumour masses was 3.5 mm, and the mean (range) age of the patients was 36.4 (26-58) years. Four men (20%) had orchidectomy because the tumours were found to be malignant; the resected specimens yielded multifocal testicular intraepithelial neoplasia (TIN) in all patients and additional seminomatous tumour cells elsewhere in the testis in one. Frozen-section results were false-negative in one patient and he had orchidectomy after having established the definitive histological diagnosis. The 16 patients with benign lesions were correctly diagnosed and their testicles were not removed.

CONCLUSIONS

Advanced and innovative ultrasonography technology allows the detection of increasingly small testicular masses. In the present series, most incidental intratesticular lesions were benign. In patients with malignant lesions, multifocal TIN and/or distant seminomatous foci were present despite the tumour being small. Therefore, it is essential to perform exploratory surgery as it is the only way to obtain accurate histological findings, thus providing oncological efficacy and precluding removal of a testicle bearing a benign lesion.

Microsurgical “testis-sparing” surgery for nonpalpable hypoechoic testicular lesions

OBJECTIVES

With the increased use of trans-scrotal ultrasonography, the unexpected detection of nonpalpable hypoechoic testicular lesions has become more frequent. The different approaches vary from radical orchiectomy to simple ultrasound follow-up, but definitive guidelines do not yet exist about the management of these lesions. We report our series of patients with hypoechoic testicular lesions who underwent surgical exploration with the aid of an operating microscope.

METHODS

A total of 7 patients were considered for microsurgical exploration of a nonpalpable hypoechoic testicular lesion from April 2003 to June 2005. The hospital records and ultrasound and operative reports were reviewed retrospectively.

RESULTS

The side of the lesion was the left testis in 4 patients and the right testis in 3. The mean size of the hypoechoic area was 5.7 +/- 4.6 mm (range 2.5 to 16). The microsurgical technique allowed us to identify and successfully excise the lesion in all patients. Intraoperative frozen section examination revealed a benign lesion in 6 cases and testicular intraepithelial neoplasia in 1. The patient with testicular intraepithelial neoplasia underwent radical orchiectomy. The definitive histologic analysis always confirmed the frozen section examination report. The patients were evaluated clinically and by ultrasonography for a mean follow-up of 15 months. No complications occurred.

CONCLUSIONS

Microsurgical exploration of the testis combined with frozen section examination represents a safe, effective, and reliable technique for evaluation of nonpalpable hypoechoic testicular lesions. This approach has significant advantages and should be considered in particular for patients with a solitary testis or presenting with bilateral lesions and wishing to father a child.

Testis Sparing Microsurgery

The unexpected detection of non palpable hypoechoic testicular lesions has become more frequent thanks to the increased use of trans-scrotal ultrasound (US): patients are often asymptomatic and the objective examination reveals no palpable masses. The different diagnostic, therapeutic approaches vary from radical orchifunicolectomy to simple US follow-up, although the guidelines on the management of these lesions are not defined, yet. The article shows our series of patients with hypoechoic testicular lesions who underwent surgical exploration, with the aid of the operating microscope and histologic test.

Materials and Methods

6 patients in total underwent microsurgical exploration of non palpable hypoechoic testicular lesions, from April 2003 to December 2004.

Results

4 out of the 6 cases were a left-sided testicular lesion, whereas the 2 remaining cases revealed a right-sided lesion [hypoechoic areas mean size = 3.9 mm (range 2.5 – 16)]. The lesions in all patients could be easily identified and successfully excised thanks to the microsurgical technique. The intraoperative frozen section examination (FSE) showed a benign lesion in 5 cases and an intratubular germ cell neoplasia (ITGCN) in one. Patient with ITGCN underwent radical orchiectomy. The final histological analysis confirmed the frozen section examination report for all the 6 cases. Patients were clinically and ultrasonographically evaluated with a mean follow-up of 15 months. No complication occurred.

Conclusion

Microsurgical exploration of the testis combined with FSE represents a safe, effective and reliable technique in case of non palpable hypoechoic testicular lesions. This approach leads to significant advantages and should be considered especially in patients with a solitary testis or presenting bilateral lesions, and wishing to father a child.

Value of frozen section analysis with suspected testicular malignancy

OBJECTIVES

To determine whether frozen section analysis (FSA) assists safe conservative surgery for men presenting with suspected testicular tumors.

METHODS

We performed a retrospective review of intraoperative testicular FSA used at a single university institution during an 11-year period. The exclusion criteria included lesions of paratesticular origin, size greater than 5 cm, and the known presence of elevated tumor markers or metastatic disease.

RESULTS

Eighty men underwent FSA, facilitating the diagnosis of germ cell malignancy in 51 (54.3%) of the 94 new cases encountered during this period. Malignancy was reported by FSA in 52 patients (65.0%), but was later revised in 3 to benign Leydig cell tumor after orchiectomy. Also, 2 of 27 specimens reported as benign by FSA were revised to malignant after analysis of paraffin-embedded tissue from the biopsies. Both were seminoma and required delayed orchiectomy. FSA was reported as "suspicious" (intratubular germ cell neoplasia with necrosis) in 1 patient, in whom orchiectomy was performed and malignancy confirmed. In total, orchiectomy was avoided in 25 cases (31.3%). The positive and negative predictive value for FSA in the diagnosis of testicular malignancy was 94.2% and 92.6%, respectively. Of 13 lesions 1 cm or less, 10 (76.9%) were benign. All 26 lesions greater than 3 cm were malignant. A clear correlation between lesion size and the diagnosis of malignancy was demonstrated.

CONCLUSIONS

FSA is a valuable tool assisting testicular preservation. Lesion size correlated with incidence of malignancy; therefore, FSA may be best used for small testicular lesions suitable for excision biopsy.

Microinvasive germ cell tumor of the testis

Microinvasive germ cell tumor (MGCT) consists of a limited number of malignant germ cells in the intertubular tissue of the testis. The cells have large nuclei, prominent nucleoli, abundant clear cytoplasm, and distinct cellular borders in hematoxylin and eosin staining. MGCT can be the first stage of malignancy in the development of testicular germ cell tumor (TGCT). Biopsies from men with maldescended testes have been reported to contain intratubular germ cell neoplasia, unclassified (IGCN) and MGCT in 1.8% of the examined cases (95% CI 0.5-4.6%). MGCT has also been found in testes of subfertile men and in the contralateral testis of patients with TGCT. MGCT is a frequent finding (19%) in the testicular tissue adjacent to an overt TGCT. Men with a high risk of TGCT may gain from screening for precursor lesions of TGCT with ultrasonography of the testes followed by a testicular biopsy if suspicious abnormalities are found: Treatment is high-voltage radiotherapy for intratubular germ cell neoplasia (IGCN), and orchidectomy for MGCT and germ cell tumor in situ, either intratubular seminoma or intratubular embryonal carcinoma. After local treatment, patients with precursor lesions can be followed with a surveillance program. The mRNA levels of invasion-related genes were evaluated based on a DNA microarray data set, and we found two gene abnormalities most relevant for the invasion of malignant germ cells: matrix metalloproteinase 9 (MMP9) and plasminogen activator, urokinase (PLAU) genes were up-regulated in a study comparing tissue samples of TGCT and IGCN.

The radiated fields of focussing air-coupled ultrasonic phased arrays

This paper presents an investigation into the fields radiated into air by ultrasonic phased arrays under transient excitation. In particular, it includes a theoretical prediction of spatial variations in amplitude throughout the both the near-field and far-field of such arrays. The approach has been used to predict the result of phasing to produce a focus in air, which can be seen to be particularly effective in the near-field of the array. Interesting features are observed, which are then described in terms of the performance of both individual elements and the resulting array. It is shown how some elements of design can be used to improve performance in focussing. The predictions are compared to the results of experiments in air using electrostatic arrays, where good focussing could be achieved provided the appropriate design principles were followed. The approach has been developed specifically for use in air, but the results would also hold for modelling in certain medical arrays where a focussing requirement might be needed close to the array itself.