The Case in Brief
A 69-year-old woman with no urinary symptoms, no haematuria and no flank pain. A routine abdominal ultrasound picked up a renal lesion. Contrast-enhanced CT characterized a 6 cm Bosniak IV solid-cystic mass in the lower pole of the right kidney. She underwent robot-assisted partial nephrectomy with ICG (Firefly™) perfusion assessment. Histopathology confirmed clear cell renal cell carcinoma, WHO/ISUP grade 2, staged pT1b with negative margins. She was discharged on day 4, walking independently, with serum creatinine moving from 0.87 mg/dL at discharge to 0.81 mg/dL at day 10.
Case at a Glance
- 6 cmBosniak IV solid-cystic mass, lower pole, right kidney
- pT1bClear cell RCC, WHO/ISUP grade 2, negative margins
- Day 4Discharged, walking independently
- >90%GFR preserved, full pentafecta achieved
- 0.81Serum creatinine mg/dL at day 10, from 0.87
Why the Kidney Could Be Preserved
At 6 cm, this tumour sat at the upper end of the T1 range, where kidney-sparing surgery is still preferred when the anatomy allows it. Two features made it feasible here: the lesion was in the lower pole rather than central or hilar, and roughly 40% of it projected outside the kidney with 60% within.
That geometry allowed the tumour to be excised with a narrow margin of healthy tissue while the remainder of the kidney was preserved and reconstructed. The decision was made at the imaging stage, not in the operating room, and the final histopathology confirmed it was the right one.
The Case, Step by Step
No haematuria, no flank pain, no urinary symptoms. The mass was an incidental finding on an ultrasound ordered for an unrelated complaint. The first decision was diagnostic rather than surgical: characterize the lesion properly before discussing anything else.
Contrast-enhanced CT characterized a Bosniak IV lesion, approximately 40% exophytic and 60% within the kidney. The imaging pointed towards malignancy, but the size and position meant partial nephrectomy remained feasible.
Using robotic magnification and articulated instruments, the tumour was excised with a thin rim of healthy tissue. Indocyanine green fluorescence imaging (Firefly™) was used intraoperatively to confirm that the preserved renal tissue retained an adequate blood supply before closure.
Histopathology confirmed clear cell renal cell carcinoma, WHO/ISUP grade 2, staged pT1b (4 to 7 cm, confined to the kidney), with negative surgical margins.
She was ambulating independently and discharged on day 4 with a serum creatinine of 0.87 mg/dL. At day 10, renal function was routine at 0.81 mg/dL. All five components of the partial nephrectomy pentafecta were met: negative margins, maximum tissue preservation, minimal ischaemia with no major complications, greater than 90% GFR preservation, and no progression to chronic kidney disease.
What This Case Shows General Practitioners
Most renal tumours are found by someone who was not looking for them. These are the points from this case that most often change what happens next in primary care.
Incidental does not mean insignificant
Most kidney tumours are discovered incidentally. An asymptomatic patient does not exclude significant pathology. This patient had no symptoms at all.
Ultrasound alone is not enough
Any solid enhancing mass, or a Bosniak IIF, III or IV lesion, warrants urological evaluation and cross-sectional imaging rather than repeat ultrasound alone.
Size alone does not decide the surgery
Tumour size is not the only determinant of approach. Partial nephrectomy is preferred for tumours up to 7 cm when anatomically feasible, as it was here at 6 cm.
Early referral preserves options
Timely referral keeps kidney-sparing options open, which matters most in elderly patients and those with diabetes, hypertension or existing chronic kidney disease.
Two findings that need urgent referral
Visible haematuria, or imaging suggesting vascular involvement, should prompt urgent urological referral rather than routine scheduling.
Function matters as much as cure
In kidney cancer the goal is oncological clearance and preserved renal function together. Both were measured and documented in this case.
Bosniak Classification, in Practice
The Bosniak system grades cystic renal lesions on contrast-enhanced imaging from I, a simple benign cyst, through to IV, where cancer is likely. A quick guide to what each category usually means for the next step.
Thin wall, no septa, no enhancement. No follow-up required.
A few thin septa, fine calcification. No follow-up required.
Multiple thin septa, minimal wall thickening. Imaging surveillance, with a urology opinion recommended.
Thickened walls with measurable enhancement. Urology referral to discuss surgery or surveillance.
Enhancing soft-tissue nodular component. Urology referral, with surgery typically recommended. This was the category in the case above.
This is a summary for quick reference. Categorization depends on contrast-enhanced CT or MRI and should be read alongside the radiologist's report and the individual clinical picture.
How to Refer a Patient
Send the CT or MRI reports with images, a recent serum creatinine or eGFR, urinalysis, a short comorbidity summary, the current medication list including anticoagulants and antiplatelets, and any relevant surgical history.
Dr. Sharma reviews the imaging and reports, then schedules an in-person consultation or a teleconsultation to discuss the findings and the options with the patient.
A written opinion is shared with the referring doctor, along with the proposed plan and, where surgery is advised, the expected pathway and follow-up.
Referrals and case discussions: phone or WhatsApp 9746552559, or email drsharmaconsults@gmail.com. Consultations are held at Bloomwell Consulting Suites, Kemps Corner, Mumbai, with teleconsultation available for patients elsewhere in India and internationally.
Have a Similar Case on Your Desk?
If a scan report has raised a question about a renal mass, a raised PSA or a complex stone, bringing the existing imaging and reports to a consultation is the most direct way to establish what the options are. Dr. Sharma is available to referring doctors for case discussion and second opinions, in person in Mumbai or by teleconsultation.
FAQs
It can be. Partial nephrectomy is generally preferred for tumours up to 7 cm when the anatomy allows it. Feasibility depends on the position of the tumour, how much of it is exophytic, its relationship to the collecting system and vessels, and the patient's baseline kidney function, rather than on size alone.
Bosniak IV describes a cystic renal lesion with an enhancing soft-tissue nodular component, which carries a high likelihood of malignancy. These lesions usually warrant urological referral and surgical consideration rather than surveillance. Bosniak III lesions also need a urology opinion, and IIF lesions need imaging surveillance with a specialist review in most cases.
Indocyanine green is a fluorescent dye viewed through near-infrared imaging on the robotic system. During partial nephrectomy it helps confirm that the kidney tissue being preserved still has an adequate blood supply after the tumour is removed and the defect is closed.
It is a composite outcome measure combining five goals: negative surgical margins, maximum preservation of healthy kidney tissue, minimal ischaemia with no major complications, more than 90% preservation of GFR, and no progression to chronic kidney disease. All five were met in this case.
Visible haematuria, or imaging that suggests vascular involvement such as renal vein or caval extension, should prompt urgent urological referral. A solid enhancing mass or a Bosniak III or IV lesion should be referred promptly even when the patient feels entirely well.
Yes. Imaging reports and investigations can be shared for review ahead of a consultation, and teleconsultation is available for patients from other cities and from abroad.
This case material is shared for professional and patient education. Patient anonymity has been maintained and no identifying details are published. Individual outcomes vary, and the findings described here relate to one patient. Treatment decisions require a full specialist evaluation.