12th May 2017, Volume 130 Number 1455

Rahul Jayakar, Jenny Choi, Craig MacKinnon, Swee Tan

Head and neck cancer (HNC) includes cancer arising from the upper aerodigestive tract (UADT; eg, oral cavity, oropharynx and larynx), major salivary glands, nasal cavity, paranasal sinuses, skull base and locally advanced and/or metastatic skin cancer.1 New Zealand has the 4th highest incidence of oral cavity cancer (OCC) after Melanesia, South-Central Asia and Central and Eastern Europe,2 and has one of the highest incidence of skin cancer in the world.3 Metastatic cutaneous squamous cell carcinoma (cSCC) is the most common cancer affecting the parotid in New Zealand and Australia.4 The incidence of HNC is greater in men, but the delayed and ongoing female smoking epidemic has led to an increased incidence of UADT cancer in women, especially in developing countries.2

Mucosal SCC (mSCC) is the commonest UADT cancer.5 The major risk factors for UADT mSCC are tobacco use and alcohol abuse, which act synergistically.6,7 They are responsible for 75% of all UADT mSCC in the US.6 Betel quid chewing remains an important risk factor for oral cavity mSCC in South Asia,8 while HPV infection has more recently emerged as an important cause of mSCC in the oropharynx, especially in younger patients.9 Sun exposure in a high risk, predominantly fair-skinned population is the main risk factor for cutaneous malignancies in New Zealand and Australia.3,10

Treatment of HNC necessitates a multidisciplinary approach, often involving surgery, radiotherapy (RT) and chemotherapy (ChT). Apart from cancer in the oropharynx, nasopharynx and larynx, surgery remains the mainstay treatment for many types of HNC. It is technically challenging as attempts to attain clear surgical margins often necessitates anatomical and functional loss that affects the quality of life of the patient.11

The heterogeneous nature of HNC, its relative rarity and over-lapping involvement of various disciplines in its management have led to the term ‘orphan cancer’.The patient and disease characteristics of HNC in New Zealand have not been well defined. Furthermore, there is a paucity of information on the cost of treatment and the resources needed for the management of HNC, worldwide and especially in New Zealand.11 Limited information is available on the cost of RT and ChT for HNC.11 However, no information is available on the cost and resources needed for surgical treatment of HNC in New Zealand.

We retrospectively analysed patient and tumour characteristics using prospectively collected data of patients undergoing major HNC surgery and quantified the cost for surgical treatment.

Methods

Patients

All patients who underwent major HNC surgery at our regional Head and Neck & Skull Base Surgery Service, June 2007–June 2012, were identified from our prospectively maintained head and neck database. Major HNC surgery was defined as local excision of a primary malignancy with neck dissection and/or parotidectomy and/or reconstruction with a regional flap or free flap and/or immediate facial reanimation. Patients who underwent surgery for benign tumours of the head and neck (eg, ameloblastoma of the mandible and pleomorphic adenoma of the salivary glands, and benign orbital or skull base tumours) and/or reconstructive surgery not performed at the time of primary HNC surgery (eg, HNC patients referred for secondary facial reanimation) or for conditions not related to HNC (eg, facial reanimation for Bells’ palsy or head and neck reconstruction for congenital anomalies) were excluded.

Data culled from the head and neck database included patient demographics, tumour type, site, stage and resection and reconstructive procedures, the length of stay (LOS), complications that occurred within six months of the initial major HNC surgery and their management including re-admission and return to theatre. Data were supplemented by information collated from patients’ electronic records to document the resources needed for their surgical treatment.

Costing methodology

The actual cost of major HNC surgery was estimated by calculating the surgeons’ and assistants’ time in theatre, theatre time, intensive care unit (ICU) and/or high dependency unit (HDU) hours and inpatient LOS. It excluded all other costs of treatment, such as incidentals (eg, medications and dressing materials) during the inpatient stay, clinic visits, family doctor visits and nursing and allied health support in the community.

In-patient days

An inpatient ‘day’ was defined as a 24-hour period including an overnight stay. Day surgery was considered to be half an inpatient day. During the admission, the patient’s stay in the ICU and/or HDU were also noted and calculated separately. An ICU admission was required for patients who needed ventilation.

Theatre time and surgeons’ time

Theatre time was defined as the time between the patient entering and leaving the operating theatre. Surgeons’ and assistants’ time were quantified as the same as theatre time. Participating surgeons were categorised by specialty and seniority (consultant or registrar).

Our hospital’s costing system quantified a bed day in the inpatient ward and ICU/HDU as NZ$502.00 and NZ$2,754.00, respectively. ICU and HDU are an integrated facility within our hospital. The cost for HDU and ICU bed days were considered to be the same according to our costing system. The theatre overhead cost was calculated at NZ$30/minute covering anaesthetic consultant, registrar, technician and equipment, theatre nurses and post-anaesthetic care. The surgeon’s time was valued at NZ$2.09/minute, and registrar’s time at NZ$1.44/minute. The actual cost of in-patient surgical treatment of HNC was calculated based on the above costing system, excluding other costs such as incidentals.

Surgical complications

All surgical complications that occurred within six months of the initial major HNC surgery and their management, including return to theatre, were recorded. Additional inpatient days to manage these complications were included in the total inpatient days. The costs of treating surgical complications occurring during the initial surgical admission were included in the total cost of the initial admission. The costs for re-admission were calculated separately. The costs of planned second-stage procedures and treatment of recurrence were also calculated separately.

Hospital income

Patient National Health Identifier and admission date obtained from our head and neck database were provided to our hospital’s data analyst, who extracted the individual Diagnosis Related Group per patient from a complex coding system. The coding system provided a Case Weight Disease (CWD) value for each episode and each CWD was multiplied by the 2013 financial year indicator of NZ$4,614.36. This provided the income received by the hospital.

Results

Patients

Two hundred and forty-five patients underwent major HNC surgery during the study period, mostly New Zealand European males (Table 1). The incidence of HNC increased with age peaking in the 8th decade of life (Figure 1). Their smoking status at diagnosis is shown in Table 1. mSCC with or without metastasis was most common (n=91, 37.1%), followed by locally advanced and/or metastatic cSCC (n=87, 35.5%). There were 20 (8.2%) cases of metastatic malignant melanoma (MM) with or without the presence of a primary tumour at presentation, and nine (3.7%) cases of salivary gland cancer. There were 11 (4.5%) cases of locally advanced basal cell carcinoma (BCC) and two cases of metastatic SCC with unknown primary. The remaining 25 (10.2%) cases consisted a heterogeneous group of rare malignancies (Table 2).

Table 1: Demographics of patients undergoing major head and neck cancer surgery.

 Age: median (range) in years

70 (11–94)

 Sex: number (%)

 Male

170 (69)

 Female

75 (31)

 Smoking status: number (%)

 Smoker

32 (13)

 Ex-smoker

101 (41)

 Non-smoker

109 (44)

 Unknown

3 (1)

 Ethnicity: number (%)

 NZ European

200 (82)

 Other European

24 (10)

 NZ Māori

11 (4)

 Other

10 (4) 

Figure 1: Number and age of patients undergoing major head and neck cancer surgery.

c 

Table 2: Types of head and neck cancer in 245 patients.

Histology

Number of patients

Mucosal SCC +/- neck metastasis

Locally advanced and/or metastatic cutaneous SCC

Metastatic melanoma +/- primary melanoma

Locally advanced BCC

Metastatic SCC with unknown primary

Other mucosal cancer +/- metastasis

Salivary gland cancer

Sarcoma

Lymphoma

Metastases from non-HNC

Other cancers

91

87

20

11

2

10

9

6

2

2

5

SCC, squamous cell carcinoma; MM, malignant melanoma; BCC, basal cell carcinoma; HNC, head and neck cancer.

Surgical treatment

HNC resection procedures

Two hundred and sixty-five major HNC resection procedures were performed in 245 patients (Table 3) with curative resection in 240 (98%) patients, including 17 (7%) salvage cases, and palliative resection in five (2%) patients. One hundred and ninety neck dissections (165 patients) were performed, followed by parotidectomy (n=73), glossectomy (n=31), hemi-maxillectomy (n=28), other wide local excision of OCC (n=28), and marginal or segmental mandibulectomy (n=25). These and other resection procedures are listed in Table 3. Thirty-six (14.6%) patients also underwent dental extraction during major HNC surgery and 36 (14.6%) had an elective tracheostomy for resection of oral cavity (n=33), laryngeal (n=1), mandibular (n=1) and maxillary sinus (n=1) cancers.

Table 3: Two hundred and sixty-five major head and neck cancer resection procedures in 245 patients.

Resection procedures

No. of procedures

Neck dissection

Parotidectomy

Superficial

Radical

Partial

Glossectomy

Subtotal

Hemi

Partial

Hemi-maxillectomy

Radical

Partial/Subtotal

Mandibulectomy

Segmental

Marginal

Other wide local excision of oral cavity cancer

Floor of mouth

Retromolar trigone

Hard palate

Buccal mucosal

Pharyngectomy

Lateral wall

Soft palate

Tonsillectomy

Laryngectomy

Orbital eesection

Orbital exenteration

Orbital wall resection

Enucleation

Resection zygomatic arch

Lateral skull base

Lateral temporal bone resection

Mastoidectomy

Resection infratemporal fossa

Resection anterior skull base

Skull resection

Full thickness

Outer table

Submandibular gland resection

Rhinectomy

Pinnectomy

Carotid endarterectomy

190

73

54

17

2

31

1§

14

16

28

2

26

25

12||

13

 

28

14

8

4

2

14

9

5

3

2

14

9

4

1

4

12

8

3

1

9

13

9

4

2

3

2

1

Unilateral in 140 patients and bilateral in 25 patients; 25 patients had sacrifice of a branch(es) of the facial nerve; §As a salvage procedure for recurrent base of tongue SCC following chemo-radiotherapy; ||Mandibular condyle was excised in two patients; One case was of base of tongue SCC extending into the glottis. 

Major HNC surgery involved plastic and cranio-maxillofacial surgeon in all (100%), dentist or oral and maxillofacial surgeon in 43 (17%), otolaryngologist in 22 (9%), neurosurgeon in 10 (4%), general surgeon in two (1%) and vascular surgeon in one (0.5%) cases.

HNC reconstructive procedures

Free (n=88), regional (n=21) or local (n=80) flaps and/or skin grafting (n=6) were performed following major HNC resection in 172 patients. Direct closure was achieved in 73 patients and immediate facial reanimation was performed in 42 patients following sacrifice of facial nerve or its branches.

Theatre time

The average theatre time for major HNC surgery was 357 (range, 58–1,867; median, 318) minutes. The procedure that took 58 minutes was for excision of a locally advanced cSCC on the cheek, including partial parotidectomy and cervicofacial flap repair.

Length of stay

Following surgery, ventilated patients were admitted to ICU, non-ventilated patients requiring intensive nursing care were admitted to HDU, with the remainder admitted directly to the inpatient ward. Average LOS following surgery was eight (range, 1–48; median, 7) days, including ICU/HDU admissions for 112 patients who stayed for a mean of 32.4 (range, 2.1–149.2; median, 23.2) hours.

A 45-year-old female who underwent resection of a retromolar trigone mSCC, including marginal mandibulectomy, ipsilateral levels I-IV neck dissection, free flap reconstruction and elective tracheostomy, became delirious three days post-operatively with deranged liver function tests due to choledocholithiasis. This patient had a history of poorly controlled epilepsy and type 1 diabetes, suffered a seizure during the admission with persistently low Phenytoin levels and poor diabetic control, and a minor oral wound dehiscence managed conservatively. An ERCP was deferred by the attending gastroenterologist and she was discharged to the Rehabilitation Service and remained in hospital for 48 days.

Patients with mSCC had the longest mean LOS (9.8 days), compared with locally advanced and/or metastatic cSCC (7.6 days). Patients with metastatic MM with or without a primary tumour at presentation had a mean LOS of 5.8 days while those with locally advanced BCC had the shortest mean LOS (4.3 days).

Patients with OCC had a mean LOS of 9.6 days compared to those with skull base tumours (10.2 days). Patients with OCC or skull base cancer had a mean LOS in the ICU/HDU of 37.5 and 42.5 hours, respectively.

Additional in-patient days for patients with surgical complications during the initial admission were included in the LOS of the primary event.

Surgical complications and re-operations

Forty-two (17%) of the 245 patients developed 59 complications within six months of surgery. Of these 38 underwent 51 re-operations acutely during the primary event. There were 14 re-admissions for complications in 13 patients who underwent eight re-operations (Table 4). The total LOS for patients re-admitted with surgical complications was 65 days with a mean of 4.6 days/re-admission.

Table 4: Fifty-nine re-operations for 42 patients who developed complications.

Procedures

Primary admission

Re-admission

Evacuation of haematoma

20

1

Free flap salvage

9

0

Revision of flap (for flap failure)

5

1

Drainage of seroma

11

1

Debridement of flap/wound

2

5

Change of dressing under GA

2

0

Closure of lymphatic leak

1

0

Debulking of flap

1

0

Acute debulking of flap to reduce pressure on orbital apex for orbital apex syndrome. 

Second-stage operations and treatment for recurrence

Twenty-five patients underwent 38 second-stage procedures with a total inpatient LOS of 81 (mean, 3.2) days (Table 5). Fifty-eight of the 245 patients developed a recurrence with 32 patients undergoing 39 salvage operations. The total LOS following surgery was 158 days with an average LOS of 4.9 (range, 1–7) days per procedure. Surgical cost estimates for second-stage procedures and for recurrence were calculated separately.

Table 5: Second-stage procedures in 23 patients.

Types of procedures

Number of procedures

Division of flap

10

Thinning of flap

21

Brow lift

1

Exchange of gold weight on upper eyelid

1

Insertion of gold weight to upper eyelid

1

Correction of ectropion

4

With insertion of a cartilage graft (n=2) and a fascial graft (n=2). 

Calculated costs for major HNC surgery

Our surgical costing methodology calculated the total cost during the initial admission for major HNC surgery at NZ$4,567,310.46 over the study period, averaging NZ$18,642.08/ patient. The total cost of second-stage procedures was calculated at NZ$200,873.69, averaging NZ$8,034.94/patient. The total cost for re-admissions for surgical complications was calculated at NZ$96,126.42, averaging NZ$6,866.17/patient. The total cost of surgery for recurrence was calculated at NZ$266,328.43, averaging NZ$8,332.71/patient. The total cost for major HNC surgery for this cohort of patients was NZ$5,130,639.00, averaging $20,941.38/patient.

mSCC was the most costly subset with a total cost of NZ$2,139,096.16 (mean, NZ$23,506.57) while cSCC had a total cost of NZ$1,643,242.30 (mean, $18,673.21). These were followed by cutaneous MM (total, NZ$234,112.34; mean, NZ$13,006.24) and BCC (total, NZ$155,361.34; mean, NZ$14,123.76).

OCC had the highest total cost of NZ$2,042,524.51, averaging $22,694.72/patient. This was followed by cutaneous malignancies (SCC, BCC and MM) with a total cost of NZ$2,032,715.98, averaging NZ$17,373.64/patient. Skull base cancer had the highest average cost of NZ$47,295.95/patient (total, NZD$425,663.55) (Table 6).

Table 6: Cost of surgical treatment for major head and neck cancer by sub-sites.

Sub-sites

Total cost (NZ$)

No. of patients

Ave. cost (NZ$)/patient

Skin cancer

cSCC

cMM

BCC

Oral cavity

Lip

Oral tongue

Floor of mouth

Retromolar trigone

Buccal mucosa

Mandibular alveolus

Maxillary alveolus

Hard palate

Tonsillar fossa

Base of tongue

Salivary gland

Skull base

Nasal cavity

Others

2,032,715.98

1,643,242.30

234,112.34

155,361.34

2,042,524.51

205,587.63

530,898.06

371,239.04

228,191.21

86,207.41

134,737.92

145,149.12

156,584.50

149,221.42

34,708.20

141,316.57

425,663.55

194,537.29

293,881.10

117

88

18

11

90

14

22

16

9

6

6

6

5

5

1

8

9

6

15

17,373.64

18,673.21

13,006.24

14,123.76

22,694.72

14,684.83

24,131.73

23,202.44

25,354.58

14,367.90

22,546.32

24,191.52

31,370.90

29,884.28

34,708.20

17,664.57

47,295.95

32,422.88

19,592.08

Salvage procedure for management of recurrent base of tongue and supraglottic SCC. 

The above calculated costs excluded all other costs of treatment of HNC, such as incidentals (eg, medications and dressing materials) during the inpatient stay, pre-operative work-up, clinic visits, family doctor visits and nursing and allied health support in the community.

Hospital income

In this study only total income from major HNC surgery for the initial admission for the 245 patients was calculated to compare with the actual calculated cost of the surgical treatment accounting for theatre time, surgeons’ time, in-patient stay including ICU/HDU admissions. Over this period the hospital income for this cohort of patients was NZ$4,976,559.61, averaging NZ$20,229.91/patient.

Discussion

HNC are a heterogeneous group of malignancies affecting different anatomical sub-sites comprising different histopathological sub-types with different risk factors. Treatment of HNC requires a multidisciplinary approach and multi-modality treatment are often necessary depending on the location, stage and histological type of the tumour, and the patient’s general health. Surgery remains the mainstay of treatment for many types of HNC, often requiring adjuvant RT and sometimes ChT.12

In 2011, there were 379 cases of OCC and 123 cases of nasal cavity, middle ear and laryngeal cancer in New Zealand.13 The estimated incidence of cSCC in New Zealand is 118/100,000 with 75–80% affecting the head and neck region3 and an estimated metastatic rate of 1.9%.14

Five-year all-cause mortality for head and neck SCC in the US is estimated at 51.3% with disease-specific mortality of 23.8%.15 In New Zealand, UADT cancer accounted for 169 deaths in 2011.13 Smoking and alcohol, that act synergistically, are the main risk factors for UADT cancer.6,7 Eighteen percent of the New Zealand population currently smoke and 26% consume alcohol 3–4 times weekly.16,17 Our study identified mSCC as the commonest malignancy reflecting the high rate of UADT cancer in New Zealand.2,13 New Zealand also has one of the highest incidence of NMSC in the world with cSCC being the second most common.3 As 75–80% of NMSC affect the head and neck region,18,19 it is not surprising that locally advanced and/or metastatic cSCC constitutes the second most common HNC in our series.

Elderly New Zealand Europeans are at greatest risk of HNC and we show a peak incidence in the 8th decade of life. Māori have a lower incidence of OCC but higher mortality rates due to poorer access to healthcare and social determinants of health (death adjusted life years of 1.22 cf NZ Europeans).20,21 Quantifying the cost of surgical treatment for HNC is challenging as the management is a continuum spanning in-patient, out-patient and community care involving medical, nursing and allied health components. Many of these patients also require RT and/or ChT. Fully estimating the cost of treatment would require inclusion of the cost of outpatient reviews and investigations, follow-up visits, post-operative surveillance, adjuvant RT and ChT, and hospice care for many patients. Invariably, patients requiring adjuvant RT and/or ChT would incur overlapping costs resulting in difficult cost estimates.

We elected to calculate the cost of surgical treatment during the initial admission and compare this with the income received by the hospital. Most of the cost of major HNC surgery consists of the personnel cost for the operative team, theatre infrastructure and LOS. These variables can be more accurately calculated while the costs of incidentals such as radiology, blood tests, medications and allied health input are difficult to quantify. The calculated hospital income of NZ$20,229.91/patient undergoing major HNC surgery appears to only marginally cover the calculated actual cost of NZ$18,642.08/patient, assuming that the incidentals and other costs are covered by the difference.

The average cost of primary surgical treatment for a HNC was calculated at NZ$18,642.08. If the cost of second-stage procedures, treatment of complications and recurrence are included, the estimated average cost increases to $20,941.38/patient.

Skull base cancer is most costly to treat while metastatic and/or locally advanced skin cancers, especially BCC, are the least costly. The location of the cancer indirectly affected ICU/HDU and inpatient LOS, thereby influencing the overall cost of treatment. Patients with mSCC had the longest LOS and hence the highest average cost, eg, OCC patients were more likely to require a tracheostomy, resulting in ICU/HDU admission and longer LOS.

A French study analyses hospital data of 36,628 HNC patients treated in the public sector over one year and attributes 23% of the annual treatment cost of £6,151–7,673 (NZ$11,164.99–13,927.65) to surgical treatment.22 Using a micro-costing method based on unit costs determined by resources used for surgery, RT and ChT, a Dutch study of 854 patients analyses the economic burden of HNC, including diagnosis and treatment cost and a two-year follow-up, estimates an average total weighted cost of €21,858.00 (NZ$33,488.20)/patient.23

Our analysis of a cross section of patients undergoing major HNC surgery in Central New Zealand, their tumour characteristics and their resection and reconstructive surgical procedures shows that HNC involves substantial financial resources.

Summary

The cost of major head and neck cancer surgery is unknown. In this study, 245 patients underwent major head and neck cancer surgery over a five-year period at the cost of NZ$5,130,639.00, averaging NZ$20,941.38 per patient. There are many different types of head and neck cancers. The cost of treatment varies depending on the type of cancer. Calculated hospital income merely covered the actual cost of major HNC surgery, which places substantial financial burden on the hospital.

Abstract

Aim

This study quantified the cost of major head and neck cancer (HNC) surgery.

Method

Consecutive patients undergoing major HNC surgery between July 2007 and June 2012 were identified from our head and neck database. Patient demographics, tumour type, site, stage and types of resection and reconstruction, length of stay and surgical complications occurring within six months of initial surgery were retrospectively analysed. The actual cost of initial surgical treatment and hospital income were calculated.

Results

Two hundred and forty-five patients underwent major HNC surgery, most commonly for mucosal squamous cell carcinoma (SCC) and metastatic and/or locally advanced cutaneous SCC. Neck dissection and parotidectomy were the commonest resection procedures and free flaps the commonest reconstructive procedures performed. Forty-two patients developed surgical complications within six months of the initial major HNC surgery. Over the five-year period, surgery cost a total of NZ$5,130,639.00, averaging NZ$20,941.38 per patient, not including costs such as incidentals, while the hospital received NZ$4,976,559.61 averaging NZ$20,229.91/patient. On average, oral cavity cancer, metastatic and/or locally advanced skin cancer, and skull base cancer cost NZ$22,694.72/patient, NZ$17,373.64/patient and NZ$47,295.95/patient, respectively.

Conclusion

Calculated hospital income marginally covered the actual cost of major HNC surgery, which places substantial financial burden on the hospital. The anatomic site of the tumour determines the cost of treatment.

Author Information

Rahul Jayakar, Wellington Regional Plastic, Maxillofacial and Burns Unit, Hutt Hospital; Jenny Choi, Gillies McIndoe Research Institute, Wellington; Craig MacKinnon, Wellington Regional Plastic, Maxillofacial and Burns Unit, Hutt Hospital; Swee Tan, Wellington Regional Plastic, Maxillofacial and Burns Unit, Hutt Hospital; and Gillies McIndoe Research Institute, Wellington.

Acknowledgements

We thank Sharon Morse, data analyst, at Hutt Hospital for her assistance in the analysis of the cost of major HNC surgery and hospital income in this study. Jenny Choi was supported by the Summer Student Scholarship at the Gillies McIndoe Research Institute.

Correspondence

Swee Tan, Gillies McIndoe Research Institute, Wellington.

Correspondence Email

swee.tan@gmri.org.nz

Competing Interests

Nil.

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