Mass Spectrometry-Based Intraoperative Tumor Diagnostics

Figures & data

Table 1. Overview about publications analyzing cancer specimen with mass spectrometric tools coupled to intraoperative sampling mechanisms.

Method	Tissue/Organ	Sample type	Statistical analysis	Reference	Year
DESI	Xenografts from FaDu cells (SCC)	Frozen tissue, margins and cell culture	PCA	Woolman et al. [42]	2017
DESI	Pancreatic cancer tissue margins	Frozen tissue	LASSO	Eberlin et al. [43]	2016
DESI	Breast cancer tissue margins	Frozen tissue	PCA	Calligaris et al. [44]	2014
DESI	Glioma	Tissue smears	PCA, LDA	Pirro et al. [45]	2017
DESI	Epithelial ovarian carcinoma	Frozen tissue	PCA	Dória et al. [46]	2016
DESI	Gastric cancer and associated lymph node metastases	Frozen tissue	RMMC discriminant analysis, PCA	Abassi-Ghadi et al. [47]	2014
DESI	Breast cancer necrosis and viable regions	Frozen tissue, tissue smears	PCA, NMF	Tata et al. [48]	2016
DESI	Surgical glioma patients	Tissue smears	PCA, LDA	Pirro et al. [56]	2017
iKnife, REIMS	Colorectal cancer and colonic adenoma	In vivo patient material (polypectomy snare)	LDA	Alexander et al. [49]	2017
iKnife, REIMS	Breast cancer	In vivo and ex vivo (fresh and fresh frozen tissue, aspirated with monopolar handpiece)	PCA, LDA	St John et al. [50]	2016
iKnife, REIMS	Gastric, colorectal, liver, breast, lung and brain cancer; healthy and cancerous tissue	In vivo and ex vivo (<10 sec after excision)	PCA, LDA	Balog et al. [51]	2013
iKnife, REIMS	Colon adenocarcinoma and adematous polyps	Ex vivo biopsy (polypectomy snare)	PCA	Balog et al. [52]	2015
MasSpec Pen	Human: breast, lung, thyroid and ovary cancer Mouse: BT474 HER2+ breast cancer cells	Human: Ex vivo, fresh tissue (< 10 sec after excision). Mouse: in vivo	LASSO, (Leave-one-patient-out-crossvalidation), PCA	Zhang et al. [53]	2017
PIRL and DESI	Necrotic and viable LM2-4 human breast cancer xenografts	Frozen tissue	PLS-DA	Woolman et al. [54]	2017
PIRL	Medulloblastoma xenografts (six cell lines, two subgroups)	Frozen tissue, tissue smears	PLS-DA	Woolman et al. [55]	2017

DESI: Desorption electrospray ionization; PCA: Principal component analysis; LASSO: Least absolute shrinkage and selection operator; LDA: Linear discriminant analysis; PIRL: Picosecond infrared laser; REIMS: Rapid evaporative ionization mass spectrometry; RMMC: Recursive maximum margin criterion analysis; NMF: Non-negative matrix factorization; PLS-DA: Partial least squares discriminant analysis.

Figure 1.  Schematic figure of mass spectrometry based methods for intraoperative cancer diagnosis (left) with corresponding examples of mass spectra (right).

(A) Desorption electrospray ionization. Left: Schematic representation of desorption electrospray ionization. Under the influence of high voltage a methanol-water solution is sprayed on the sample surface, dissolving desorbed ions to be transferred in the atmospheric inlet of the mass spectrometer. Parameters like voltage, gas and liquid flow rate can be set. Right: Average lipid profile spectrum for all pixels images used for chemical prediction. Reproduced with permission from [45]. (B) iKnife. Left: Schematic illustration of rapid evaporative mass spectrometry coupled to eligible surgical devices. Surgical ion source and ion transfer setups for rapid evaporative mass spectrometry experiments are demonstrated using an endoscope, monopolar electrosurgery or commercially available bipolar electrosurgery. The aerosol is aspirated by an air jet pump through a teflon tube with a maximum of 3 m length. By histological validation and Principal Component Analysis, in a second run the recognition software differentiates cancer and normal tissue by comparing signal intensities in the recorded mass spectra. Most of the signals in the spectra represent lipid ions. Right: Mean spectral intensity for cancer and normal tissues during cutting. Reproduced with permission from [50]. (C) MasSpec pen. Left: A handheld device (MasSpec pen) is positioned on the sample surface and through the inlet channel a water droplet is exposed for 1 s to extract molecules from the tissue surface. Then, the channel is closed and after 2 s, gas inlet is opened to transport the water droplet (volume controlled by a syringe pump) via polytetrafluorethylen (PTFE) tubing driven by vacuum into the mass spectrometer. The system is triggered by a foot pedal connected to an integrated mass spectrometer inlet. Right: Representative negative ion mode mass spectra show distinct molecular profiles from normal (average of n = 3 mass spectra) and tumor (average of n = 3 mass spectra) tissues [53]. (D) Picosecond infrared laser. Left: Current instrument for sampling of tissue with picosecond infrared laser. For cryopreserved samples, the specimen stage is cooled down to -10°C, preventing thawing during laser irradiation. The ablation chamber is sealed to capture the aerosol in its complete volume, achieved by its architecture generating a laminar flow. The aerosol is trapped through PTFE-tubing as a frozen (cooling trap) or dry (glass fiber filter) condensate within seconds. Instead of the free laser beam a fiber can be utilized to adjust and operate flexibly. Right: Negative ion mode mass spectrum from picosecond infrared laser condensate of porcine thalamus (upper) and cerebral cortex (lower) directly infused into the MS without sample preparation.

HV: High voltage; IPA: Isopropyl alcohol; PIRL: Picosecond infrared laser.

Table 2. Overview of mass spectrometry-based methods for intraoperative cancer diagnosis.

Quality	Method	DESI	iKnife	MasSpec pen	DESI-PIRL	PIRL
Speed		1 s per sampling point [108]	<2 s [50]	3 s per sampling point [53]	5–10 s per sampling point [55]	<5 s
Cross contamination		No	Yes	No	No	No
Invasiveness		Yes	Yes	No	Yes minimal	Yes minimal
Pre-analytical issues		Redox reactions can be assumed [109,110]	Heat degradation, carbonization	Unlikely	Not observed	Not observed
Surface scanning		No	No	Yes, discontinuously	Yes	Yes
Cutting abilities		No	Yes	No	No	Yes
Resolution		Electrospray: 200 μm [47,74]	Blade: 4 mm [50]	Probe tip: 1.5–5 mm diameter [53]	Fibre: 425 μm [54,55]	Fibre: 200–250 μm [104,111] Free beam: 250 μm [97]
Tissue damage		Low	High	Very low	Low	Low, minimal scar formation [103]

DESI: Desorption electrospray ionization; PIRL: Picosecond infrared laser.

Woolman M, Tata A, Dara D et al. Rapid determination of the tumour stroma ratio in squamous cell carcinomas with desorption electrospray ionization mass spectrometry (DESI-MS): a proof-of-concept demonstration. Analyst 142(17), 3250–3260 (2017).

 PubMed Web of Science ®Google Scholar

Eberlin LS, Margulis K, Planell-Mendez I et al. Pancreatic cancer surgical resection margins: molecular assessment by mass spectrometry imaging. PLoS Med. 13(8), e1002108 (2016).

 PubMed Web of Science ®Google Scholar

Calligaris D, Caragacianu D, Liu X et al. Application of desorption electrospray ionization mass spectrometry imaging in breast cancer margin analysis. Proc. Natl Acad. Sci. USA 111(42), 15184–15189 (2014).

 PubMed Web of Science ®Google Scholar

Pirro V, Jarmusch AK, Alfaro CM, Hattab EM, Cohen-Gadol AA, Cooks RG. Utility of neurological smears for intrasurgical brain cancer diagnostics and tumour cell percentage by DESI-MS. Analyst 142(3), 449–454 (2017).

 PubMed Web of Science ®Google Scholar

Doria ML, Mckenzie JS, Mroz A et al. Epithelial ovarian carcinoma diagnosis by desorption electrospray ionization mass spectrometry imaging. Sci. Rep. 6, 39219 (2016).

 PubMed Web of Science ®Google Scholar

Abbassi-Ghadi N, Veselkov K, Kumar S et al. Discrimination of lymph node metastases using desorption electrospray ionisation-mass spectrometry imaging. Chem. Commun. (Camb.) 50(28), 3661–3664 (2014).

 PubMed Web of Science ®Google Scholar

Tata A, Woolman M, Ventura M et al. Rapid detection of necrosis in breast cancer with desorption electrospray ionization mass spectrometry. Sci. Rep. 6, 35374 (2016).

 PubMed Web of Science ®Google Scholar

Pirro V, Alfaro CM, Jarmusch AK, Hattab EM, Cohen-Gadol AA, Cooks RG. Intraoperative assessment of tumor margins during glioma resection by desorption electrospray ionization-mass spectrometry. Proc. Natl Acad. Sci. USA 114(26), 6700 (2017).

 PubMed Web of Science ®Google Scholar

Alexander J, Gildea L, Balog J et al. A novel methodology for in vivo endoscopic phenotyping of colorectal cancer based on real-time analysis of the mucosal lipidome: a prospective observational study of the iKnife. Surg. Endosc. 31(3), 1361–1370 (2017).

 PubMed Web of Science ®Google Scholar

St John ER, Balog J, Mckenzie JS et al. Rapid evaporative ionisation mass spectrometry of electrosurgical vapours for the identification of breast pathology: towards an intelligent knife for breast cancer surgery. Breast Cancer Res. 19(1), 59 (2017).

 PubMedGoogle Scholar

Balog J, Sasi-Szabo L, Kinross J et al. Intraoperative tissue identification using rapid evaporative ionization mass spectrometry. Sci. Transl. Med. 5(194), 193–194 (2013).

 Web of Science ®Google Scholar

Balog J, Kumar S, Alexander J et al. In vivo endoscopic tissue identification by rapid evaporative ionization mass spectrometry (REIMS). Angew. Chem. (Int. Ed. English) 54(38), 11059–11062 (2015).

 PubMed Web of Science ®Google Scholar

Zhang J, Rector J, Lin JQ et al. Nondestructive tissue analysis for ex vivo and in vivo cancer diagnosis using a handheld mass spectrometry system. Sci. Transl. Med. 9(406), (2017).

 Web of Science ®Google Scholar

Woolman M, Gribble A, Bluemke E et al. Optimized mass spectrometry analysis workflow with polarimetric guidance for ex vivo and in situ sampling of biological tissues. Sci. Rep. 7(1), 468 (2017).

 PubMedGoogle Scholar

Woolman M, Ferry I, Kuzan-Fischer CM et al. Rapid determination of medulloblastoma subgroup affiliation with mass spectrometry using a handheld picosecond infrared laser desorption probe. Chem. Sci. 8(9), 6508–6519 (2017).

 PubMed Web of Science ®Google Scholar

Tillner J, Wu V, Jones EA et al. Faster, more reproducible DESI-MS for biological tissue imaging. J. Am. Soc. Mass Spectrom. 28(10), 2090–2098 (2017).

 PubMed Web of Science ®Google Scholar

Jurva U, Wikstrom HV, Weidolf L, Bruins AP. Comparison between electrochemistry/mass spectrometry and cytochrome p450-catalyzed oxidation reactions. Rapid Commun. Mass Spectrom. : RCM 17(8), 800–810 (2003).

 PubMed Web of Science ®Google Scholar

Liu P, Lanekoff IT, Laskin J, Dewald HD, Chen H. Study of electrochemical reactions using nanospray desorption electrospray ionization mass spectrometry. Anal. Chem. 84(13), 5737–5743 (2012).

 PubMed Web of Science ®Google Scholar

Margulis K, Chiou AS, Aasi SZ, Tibshirani RJ, Tang JY, Zare RN. Distinguishing malignant from benign microscopic skin lesions using desorption electrospray ionization mass spectrometry imaging. Proc. Natl Acad. Sci. USA 115(25), 6347–6352 (2018).

 PubMed Web of Science ®Google Scholar

Petersen H, Gliese A, Stober Y et al. Picosecond infrared laser (PIRL) application in stapes surgery – first experience in human temporal bones. Otol. Neurotol. 39(4), e224–230 (2018).

 PubMed Web of Science ®Google Scholar

Mehlan J, Uschold S, Hansen NO et al. Picosecond infrared laser fiber-assisted sclerostomy (PIRL-FAST): a first proof of principle analysis. Ophthalmologe 9, 899–915 (2018).

 Google Scholar

Bottcher A, Kucher S, Knecht R et al. Reduction of thermocoagulative injury via use of a picosecond infrared laser (PIRL) in laryngeal tissues. Eur. Arch. Otorhinolaryngol. 272(4), 941–948 (2015).

 PubMed Web of Science ®Google Scholar

Petersen H, Tavakoli F, Kruber S et al. Comparative study of wound healing in rat skin following incision with a novel picosecond infrared laser (PIRL) and different surgical modalities. Lasers Surg. Med. 48(4), 385–391 (2016).

 PubMed Web of Science ®Google Scholar