Technology overview | ERBE flexible cryoprobes for bronchoscopic diagnosis and treatment | Advice

About the technology

CE marking

ERBE flexible cryoprobes and associated systems (ERBE Elektromedizin) received CE marking under the Medical Devices Directive 1993/42/EEC on 24 July 1998 (ERBOKRYO CA) and 15 April 2014 (ERBECRYO 2) as class IIb devices.

Description

ERBE flexible cryoprobes are used for diagnostic biopsies and therapeutic procedures during bronchoscopy. There are 7 ERBE flexible cryoprobes, which differ in diameter and length. They are compatible with all flexible bronchoscopes. ERBE Elektromedizin has 2 system models that connect to ERBE flexible cryoprobes (see table 1).

Table 1 ERBE flexible cryoprobes

Product number	Length, diameter (mm)	Compatibility with ERBE system models
Product number	Length, diameter (mm)	ERBECRYO 2	ERBOKRYO CA
20402‑037	900, 1.9	Yes	No
20402‑040	1050, 1.9	Yes	No
20402‑032	900, 2.4	Yes	No
20416‑038	780, 1.9	No	Yes
20416‑037	900, 1.9	No	Yes
20416‑033	780, 2.4	No	Yes
20416‑032	900, 2.4	No	Yes

Both systems use the Joule–Thomson effect, in which pressurised gas is forced through a small nozzle within the end of the cryoprobe to produce an extreme drop in temperature. The low temperature freezes the cryoprobe that, in turn, freezes the target tissue to destroy or remove tissue. The system is closed and gas does not come into direct contact with the tissue.

As well as the flexible cryoprobes, the ERBE systems include:

An ERBE cryosurgery unit – the ERBOKRYO CA unit has an analogue switch and basic display (lights indicating whether the footswitch is activated and the machine is on), whereas the ERBECRYO 2 has a digital display which shows a timer (showing duration of activation), the effect level (indicating temperature), and a plug‑and‑play feature that detects and displays the type of cryoprobe (length and item number), footswitch and gas bottle in use. The clinical functionality of the units is the same.
A single‑pedal footswitch to activate and deactivate the freezing process.
A gas bottle connector.
A flexible gas hose.

Hospitals must provide the bottles of carbon dioxide or nitrous oxide necessary to operate the systems. The ERBECRYO 2 only uses carbon dioxide whereas the ERBOKRYO CA can use either carbon dioxide or nitrous oxide.

Setting and intended use

ERBE flexible cryoprobes are intended for cryobiopsy, cryorecanalisation and cryonecrosis using bronchoscopy.

The procedures are done in secondary care settings by medical professionals trained in bronchoscopy. Although professionals should read the user manual before using the ERBECRYO system, no additional training is needed. In the UK, the procedure will most commonly be done by a thoracic surgeon or a respiratory/chest physician.

The manufacturer does not list any contraindications for this device.

Current NHS options

According to NICE's guideline on lung cancer, people with known or suspected lung cancer should have a chest CT scan before bronchoscopy or other biopsy procedures. Fibre‑optic bronchoscopy can be used to diagnose and stage lung cancer. NICE's guideline recommends offering this to patients with central lesions shown on a CT scan when nodal staging does not influence treatment.

The British Thoracic Society (BTS) guideline for advanced diagnostic and therapeutic flexible bronchoscopy in adults lists 7 therapeutic procedures for debulking endobronchial tumours via flexible bronchoscope: argon plasma coagulation, brachytherapy, cryorecanalisation, cryotherapy, electrocautery, photodynamic therapy, and thermal laser such as neodymium‑doped yttrium aluminium garnet laser. It notes that cryotherapy is mainly indicated as a palliative measure for cancerous airway obstruction, but that it may be indicated for the curative treatment of low‑grade cancerous lesions and early cancer. The BTS guideline also states that cryotherapy can be used to remove foreign bodies and blood clots.

Rigid bronchoscopic debulking procedures are also used to treat airway obstructions (see the NICE clinical guideline on lung cancer).

NICE is not aware of any other CE‑marked devices that have a similar function to the ERBE flexible cryoprobes for bronchoscopy.

Costs and use of the technology

The typical list price for the ERBECRYO 2 system is £10,051, excluding VAT. This includes 1 reuseable cryoprobe. The manufacturer states that ERBE flexible cryoprobes can be used for up to 100 procedures. The cryoprobes are autoclaved before re‑use. The average lifespan of the cryotherapy systems is unknown but the manufacturer estimates it to be at least 10 years. Technical safety checks must be done by the manufacturer at least once per year.

Forceps can be used as an alternative for cryobiopsy or cryorecanalisation. The weighted average cost of bronchoscopy is £734.96 for fibre‑optic bronchoscopy in adults aged 19 years and over (NHS reference cost 2013–2014 code DZ07A), fibre‑optic bronchoscopy in children aged 18 years and under (DZ07B), rigid bronchoscopy (DZ08Z) and complex bronchoscopy (DZ54Z). If the average cost for forceps and an endobronchial pack (£28.56) is added, the total cost is £763.52.

Brachytherapy can be used as an alternative for recanalisation or debulking of lung tumours (Du Rand et al. 2011). The cost of preparation and delivery of intraluminal brachytherapy (SC53Z and SC30Z), including the average cost of bronchoscopy (£1787.96), is between £3272.96 and £13,424.96 for 1 to 5 fractions (or treatment sessions) of radiotherapy respectively.

Likely place in therapy

ERBE flexible cryoprobes would be used as an alternative to forceps to provide large‑volume lung biopsy specimens. For airway recanalisation and cryonecrosis, they would be used as alternatives to other debulking methods.

Specialist commentator comments

One specialist stated that ERBE cryoprobes are unlikely to be used solely for diagnostic purposes. Instead, their place in therapy is likely to be for recanalisation, cryonecrosis and diagnosis in patients with cancerous airway obstruction, or for treating select cases of non‑cancerous endobronchial tumours. Another commentator noted that cryoprobes could be used for iatrogenic granulation tissue overgrowth — a benign tracheal disease — which can occur after the insertion of tracheal or bronchial stents. One commentator explained that cryotherapy is likely to be 1 of several endobronchial techniques used for treating cancerous critical airway obstruction, saying others include stents, argon plasma coagulation or laser treatment. Two specialist commentators stated that cryotherapy is unlikely to be suitable for the treatment of non‑cancerous tracheal stenosis.

One specialist commentator stated that positron emission tomography (PET) CT scanning is used to confirm staging and inform the best approach for biopsy. The specialist was of the opinion that endobronchial ultrasound‑guided fine needle aspiration (EBUS‑FNA) biopsies are increasingly used for diagnosis, so cryoprobes should be compared directly with EBUS‑FNA to assess their value. However, there were different views between commentators as to whether EBUS‑FNA and cryotherapy were alternative, or complementary, techniques; 1 commentator considered that EBUS‑FNA is used to sample lung tissue for a different purpose and so comparison with cryoprobes would not be appropriate.

One commentator explained that experience with cryobiopsy samples has shown that they are more suitable for pathological assessment than those obtained using comparator techniques because they do not have crush artefact, are larger, and permit histopathological assessment (not cytology alone).

All commentators noted that there is little evidence about the cost‑effectiveness of cryotherapy and alternative techniques for endobronchial recanalisation or biopsy, and also a lack of evidence about which endobronchial technique is most effective. One commentator stated that the cost of cryotherapy is more modest than other techniques, so it is highly likely that it would be cost effective. Another commentator noted that cryotherapy is likely to cost less than laser therapy.

One specialist commentator remarked on the importance of cryoprobe operators learning under supervision, particularly because of the challenging clinical problems that bleeding can introduce to the procedure. In contrast, another specialist noted that use of the ERBE cryoprobe is easily learned, may be associated with less bleeding than alternative debulking methods, and can be used with fibre‑optic bronchoscopes. A third specialist commentator explained that electrocautery is more widely used than neodymium‑doped yttrium aluminium garnet laser, is less costly, and does not need safety regulation and training.

Finally, 1 specialist commentator indicated that their experience of cryorecanalisation in the NHS was similar to that reported in the study by Schumann et al. (2010b).

Equality considerations

NICE is committed to promoting equality and eliminating unlawful discrimination. In producing guidance, NICE aims to comply fully with all legal obligations to:

promote race and disability equality and equality of opportunity between men and women
eliminate unlawful discrimination on grounds of race, disability, age, sex, gender reassignment, pregnancy and maternity (including women post‑delivery), sexual orientation, and religion or belief (these are protected characteristics under the Equality Act 2010).

ERBE flexible cryoprobes may be beneficial for people with poor respiratory function caused by long‑term lung diseases such as chronic obstructive pulmonary disease (COPD). Chronic conditions such as COPD may adversely affect activities of daily living to the extent that people may be considered to be disabled. Disability is a protected characteristic under the Equality Act 2010.