For small early-stage lung cancers, a segmentectomy — removing one anatomical segment of the lung rather than the whole lobe — now offers equivalent cancer control with significantly more healthy lung preserved. Two landmark international trials (JCOG0802, CALGB 140503) have confirmed this. Dr Okiror offers private robotic segmentectomy at London Bridge Hospital and The Lister Hospital Chelsea, built on the clinical standards he helps set at Guy’s and St Thomas’ — where he is Clinical Audit Lead for Thoracic Surgery.
Last reviewed: April 2026 · Dr Lawrence Okiror FRCS(CTh) FRCSEd(CTh) · GMC 6150382
Dr Okiror’s private practice at London Bridge Hospital and The Lister Hospital Chelsea is informed by the clinical standards he helps set, audit and publish at Guy’s and St Thomas’ — one of the UK’s largest thoracic surgery centres and his NHS base. The numbers below are what make segmentectomy a credible, defensible option for the right patient. They are what a second opinion should be measured against.
The Benchmark
Guy’s and St Thomas’
Dr Okiror’s NHS base · one of the UK’s largest thoracic surgery centres · source of the clinical standards he brings to private practice
23.8%
Segmentectomy rate of anatomic lung cancer resections — approximately 2–3x the UK national average of 8–12%
91%
Of segmentectomies performed robotically — reflecting the technical precision the operation demands
99.16%
Operative survival rate for primary lung cancer surgery — vs 98.5% national average
6%
Wedge resection rate — vs 14% national average, reflecting a deliberate commitment to anatomically precise surgery over less precise alternatives
Source: SCTS National Thoracic Audit 2024–25.
The Surgeon
Dr Lawrence Okiror
Consultant Thoracic & Robotic Surgeon · Clinical Audit Lead, Thoracic Surgery · the surgeon who will see you at London Bridge Hospital or The Lister Hospital Chelsea
22.7%
Personal robotic segmentectomy rate of anatomic robotic resections in 2024–25 — mirroring the institutional benchmark almost exactly
80%+
Career-wide personal rate of anatomic lung cancer resections performed by robotic or keyhole (minimally invasive) approach
For Thoracic Surgery at GSTT — the role responsible for tracking, auditing and publishing the outcomes shown opposite
MIST-4 and PRO-SEAL — UK multicentre thoracic surgical trials
The 22.7% alignment between Dr Okiror’s personal rate and the 23.8% institutional rate is not coincidence. The institution sets the benchmark; Dr Okiror, as Clinical Audit Lead, helps to shape it — and brings it to every private patient at London Bridge Hospital and The Lister Hospital Chelsea.
The human lung is divided into five lobes — three on the right and two on the left. Each lobe is further divided into anatomical segments, each with its own dedicated blood supply, airway, and draining lymph nodes. The lung has approximately 18 such segments in total.
A segmentectomy removes one segment together with its dedicated blood vessels, airway, and lymph nodes — typically around 5–6% of total lung volume. A lobectomy, by comparison, removes an entire lobe — typically 15–20% of lung volume. A wedge resection removes a non-anatomical piece of lung without regard for segmental boundaries, and is clinically inferior for primary lung cancer because it does not remove the draining lymph nodes needed for accurate staging.
Segmentectomy is therefore the most precise sublobar operation available for early-stage lung cancer. It preserves more healthy lung than a lobectomy, while delivering the complete anatomical resection — including lymph node clearance — that wedge resection cannot. Robotic lung surgery overview →
Segmentectomy requires accurate identification of the intersegmental plane — the invisible boundary between the target segment and the segments to be preserved. This plane must be defined precisely to deliver adequate oncological margins without damaging adjacent structures. The da Vinci Xi robotic platform provides magnified 3D visualisation, wristed instrument articulation, and tremor filtration that make this dissection significantly more reproducible than conventional keyhole surgery.
For nearly three decades, lobectomy was the default operation for early-stage lung cancer. Two large international randomised trials have now established that, for selected small tumours, segmentectomy is equivalent or superior. This is not emerging evidence. It is settled science.
Japan · 2022
Saji et al. · The Lancet · 2022 · 1,106 patients randomised
For peripheral non-small-cell lung cancers of 2cm or less, segmentectomy demonstrated superior five-year overall survival compared to lobectomy (94.3% vs 91.1%). Local recurrence was slightly higher with segmentectomy but did not translate into worse cancer-specific survival.
The preservation of lung function translated into improved overall survival — the first evidence that lung-sparing surgery not only matched but exceeded lobectomy for this patient group.
USA · 2023
Altorki et al. · New England Journal of Medicine · 2023 · 697 patients randomised
For peripheral non-small-cell lung cancers of 2cm or less, sublobar resection (predominantly segmentectomy) demonstrated non-inferior disease-free and overall survival compared to lobectomy at five years. Lung function preservation was significantly better with sublobar resection.
Confirmed the JCOG0802 finding in a Western population. Together, the two trials have established segmentectomy as an acceptable — and in many cases preferable — operation for small early-stage lung cancer.
The Boundaries of the Evidence
Both trials restricted eligibility to peripheral tumours of 2cm or less with no clinical evidence of lymph node involvement. For tumours larger than 2cm, centrally located tumours, or tumours with suspicion of N1 or N2 nodal disease on PET-CT or staging, lobectomy remains the standard of care. Segmentectomy is not a shortcut. It is a precision operation reserved for the patients whose disease makes it the right choice.
For most of the history of lung cancer surgery, the operation was a lobectomy because the tumours being found were too large for anything smaller. Lung cancer typically presented with symptoms — cough, breathlessness, weight loss — by which stage the tumour was already substantial. Historically, fewer than 30% of lung cancers were diagnosed at Stage I or II.
CT screening has inverted this. Five-year data from the NHS Lung Cancer Screening Programme, published in Nature Medicine in March 2026, shows that over 75% of screen-detected cancers are now found at Stage I or II — the earliest, most curable, and smallest stages. Many of these cancers fall within the 2cm size threshold for which JCOG0802 and CALGB 140503 have now established segmentectomy as equivalent to lobectomy.
The clinical argument is therefore no longer theoretical. It reflects the actual changing landscape of how lung cancer is detected — and how many more patients now have the option of a lung-sparing operation that was not available to the generation before them. Targeted lung health check →
IASLC data from 77,156 patients (Rami-Porta, JTO 2015), validated in 124,581 patients (Van Schil, JTO 2024), shows five-year survival varies significantly within Stage I based on tumour size alone:
T1a
≤1cm
92%
T1b
>1–2cm
83%
T1c
>2–3cm
76%
From 1cm to 3cm, every centimetre counts. Finding cancer small — and operating on it with a segmentectomy where appropriate — is what screening makes possible. Read more →
Small peripheral nodules are not always visible at the lung surface. During ION bronchoscopy biopsy, a fluorescent dye marker can be placed at the exact nodule site. At subsequent surgery, the da Vinci robotic system’s infrared camera detects this marker, guiding the segmentectomy precisely to the tumour. This integrated diagnostic and surgical pathway, available privately at London Bridge Hospital, enables segmentectomy in cases where the nodule would otherwise be difficult to locate.
A segmentectomy is not inherently better than a lobectomy. It is a precision operation appropriate for a specific clinical context. For patients whose disease falls outside that context, lobectomy remains the correct choice — and delivering a segmentectomy where a lobectomy is indicated would compromise oncological outcomes.
Both JCOG0802 and CALGB 140503 restricted eligibility to tumours of 2cm or less. For larger tumours, lobectomy delivers superior cancer control. Size remains the single most important determinant.
Tumours close to the main airways or central blood vessels cannot be removed with adequate oncological margins by segmentectomy. The anatomical plane does not exist in the same way centrally as it does in the periphery.
Where PET-CT or mediastinal staging suggests N1 or N2 nodal disease, lobectomy with formal lymphadenectomy remains the standard of care. Segmentectomy does not deliver equivalent nodal clearance in this context.
At consultation, Dr Okiror reviews CT and PET-CT imaging personally, integrates the Herder score where available, and discusses with the multidisciplinary team before recommending the most appropriate operation for your specific tumour.
Dr Okiror consults and operates at both London Bridge Hospital and The Lister Hospital Chelsea. Both hospitals offer full robotic surgical capability.
For most segmentectomies, either hospital is an excellent setting. The choice is usually determined by convenience — Chelsea or the City.
Where a case requires the integrated ION bronchoscopy pathway — a small peripheral nodule marked at biopsy with fluorescent dye for precise surgical localisation — surgery takes place at London Bridge Hospital, where this capability is uniquely available to private patients.
Patients first seen at The Lister who require this specific pathway are not turned away. The surgical episode is arranged at LBH, while consultations and follow-up can continue at whichever hospital is more convenient. Dr Okiror will make the recommendation that matches your case.
Common questions from patients offered lung cancer surgery who want to understand whether segmentectomy is the right operation for them.
Book a Consultation →Or call Jo Mitchelson:
020 7952 2882
Appointments within 2–3 days. Self-referrals welcome. Surgery at London Bridge Hospital and Lister Hospital Chelsea.
Jo Mitchelson, Private PA · 020 7952 2882 · pa@lungsurgeon.co.uk
St Thomas' Hospital #1 UK · Guy's Hospital #2 UK · London Bridge Hospital #10 UK · Newsweek World’s Best Hospitals 2026
The full robotic lung cancer surgery service — lobectomy, segmentectomy, complex cases
ION BronchoscopyRobotic biopsy for peripheral nodules — with fluorescent marking to guide subsequent segmentectomy
Lung Nodule Precision PathwayFrom scan review through biopsy to surgery — one consultant, no handoffs